Ignore:
Timestamp:
15/07/12 02:55:39 (9 years ago)
Author:
fielding@…
Message:

Update p2 introduction and replace redundancies with reference to p1

Location:
draft-ietf-httpbis/latest
Files:
2 edited

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  • draft-ietf-httpbis/latest/p2-semantics.html

    r1778 r1781  
    481481      <link rel="Chapter" title="9 Header Field Definitions" href="#rfc.section.9">
    482482      <link rel="Chapter" title="10 IANA Considerations" href="#rfc.section.10">
    483       <link rel="Chapter" title="11 Security Considerations" href="#rfc.section.11">
    484       <link rel="Chapter" title="12 Acknowledgments" href="#rfc.section.12">
    485       <link rel="Chapter" href="#rfc.section.13" title="13 References">
     483      <link rel="Chapter" title="11 ABNF Rules Defined Elsewhere" href="#rfc.section.11">
     484      <link rel="Chapter" title="12 Security Considerations" href="#rfc.section.12">
     485      <link rel="Chapter" title="13 Acknowledgments" href="#rfc.section.13">
     486      <link rel="Chapter" href="#rfc.section.14" title="14 References">
    486487      <link rel="Appendix" title="A Differences between HTTP and MIME" href="#rfc.section.A">
    487488      <link rel="Appendix" title="B Additional Features" href="#rfc.section.B">
    … …  
    499500      <meta name="dct.issued" scheme="ISO8601" content="2012-07-14">
    500501      <meta name="dct.replaces" content="urn:ietf:rfc:2616">
    501       <meta name="dct.abstract" content="The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypertext information systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 2 of the seven-part specification that defines the protocol referred to as &#34;HTTP/1.1&#34; and, taken together, obsoletes RFC 2616. Part 2 defines the semantics of HTTP messages as expressed by request methods, request header fields, response status codes, and response header fields. Furthermore, it defines HTTP message content, metadata, and content negotiation.">
    502       <meta name="description" content="The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypertext information systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 2 of the seven-part specification that defines the protocol referred to as &#34;HTTP/1.1&#34; and, taken together, obsoletes RFC 2616. Part 2 defines the semantics of HTTP messages as expressed by request methods, request header fields, response status codes, and response header fields. Furthermore, it defines HTTP message content, metadata, and content negotiation.">
     502      <meta name="dct.abstract" content="The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypertext information systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 2 of the six-part specification that defines the protocol referred to as &#34;HTTP/1.1&#34;. Part 2 defines the semantics of HTTP messages, as expressed by request methods, request header fields, response status codes, and response header fields, the payload of messages as metadata and body content, and the mechanisms for content negotiation.">
     503      <meta name="description" content="The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypertext information systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 2 of the six-part specification that defines the protocol referred to as &#34;HTTP/1.1&#34;. Part 2 defines the semantics of HTTP messages, as expressed by request methods, request header fields, response status codes, and response header fields, the payload of messages as metadata and body content, and the mechanisms for content negotiation.">
    503504   </head>
    504505   <body onload="init();">
    … …  
    541542      <p>The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypertext information
    542543         systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 2 of the
    543          seven-part specification that defines the protocol referred to as "HTTP/1.1" and, taken together, obsoletes RFC 2616.
     544         six-part specification that defines the protocol referred to as "HTTP/1.1".
    544545      </p> 
    545       <p>Part 2 defines the semantics of HTTP messages as expressed by request methods, request header fields, response status codes,
    546          and response header fields. Furthermore, it defines HTTP message content, metadata, and content negotiation.
     546      <p>Part 2 defines the semantics of HTTP messages, as expressed by request methods, request header fields, response status codes,
     547         and response header fields, the payload of messages as metadata and body content, and the mechanisms for content negotiation.
    547548      </p>
    548549      <h1 id="rfc.note.1"><a href="#rfc.note.1">Editorial Note (To be removed by RFC Editor)</a></h1>
    … …  
    580581      <h1 class="np" id="rfc.toc"><a href="#rfc.toc">Table of Contents</a></h1>
    581582      <ul class="toc">
    582          <li>1.&nbsp;&nbsp;&nbsp;<a href="#introduction">Introduction</a><ul>
    583                <li>1.1&nbsp;&nbsp;&nbsp;<a href="#terminology">Terminology</a></li>
    584                <li>1.2&nbsp;&nbsp;&nbsp;<a href="#intro.conformance.and.error.handling">Conformance and Error Handling</a></li>
    585                <li>1.3&nbsp;&nbsp;&nbsp;<a href="#notation">Syntax Notation</a><ul>
    586                      <li>1.3.1&nbsp;&nbsp;&nbsp;<a href="#core.rules">Core Rules</a></li>
    587                      <li>1.3.2&nbsp;&nbsp;&nbsp;<a href="#abnf.dependencies">ABNF Rules defined in other Parts of the Specification</a></li>
    588                   </ul>
    589                </li>
    590             </ul>
    591          </li>
     583         <li>1.&nbsp;&nbsp;&nbsp;<a href="#introduction">Introduction</a></li>
    592584         <li>2.&nbsp;&nbsp;&nbsp;<a href="#methods">Methods</a><ul>
    593585               <li>2.1&nbsp;&nbsp;&nbsp;<a href="#safe.and.idempotent">Safe and Idempotent Methods</a><ul>
    … …  
    738730            </ul>
    739731         </li>
    740          <li>11.&nbsp;&nbsp;&nbsp;<a href="#security.considerations">Security Considerations</a><ul>
    741                <li>11.1&nbsp;&nbsp;&nbsp;<a href="#security.sensitive">Transfer of Sensitive Information</a></li>
    742                <li>11.2&nbsp;&nbsp;&nbsp;<a href="#encoding.sensitive.information.in.uris">Encoding Sensitive Information in URIs</a></li>
    743                <li>11.3&nbsp;&nbsp;&nbsp;<a href="#location.spoofing-leakage">Location Header Fields: Spoofing and Information Leakage</a></li>
    744                <li>11.4&nbsp;&nbsp;&nbsp;<a href="#rfc.section.11.4">Security Considerations for CONNECT</a></li>
    745                <li>11.5&nbsp;&nbsp;&nbsp;<a href="#privacy.issues.connected.to.accept.header.fields">Privacy Issues Connected to Accept Header Fields</a></li>
     732         <li>11.&nbsp;&nbsp;&nbsp;<a href="#abnf.dependencies">ABNF Rules Defined Elsewhere</a></li>
     733         <li>12.&nbsp;&nbsp;&nbsp;<a href="#security.considerations">Security Considerations</a><ul>
     734               <li>12.1&nbsp;&nbsp;&nbsp;<a href="#security.sensitive">Transfer of Sensitive Information</a></li>
     735               <li>12.2&nbsp;&nbsp;&nbsp;<a href="#encoding.sensitive.information.in.uris">Encoding Sensitive Information in URIs</a></li>
     736               <li>12.3&nbsp;&nbsp;&nbsp;<a href="#location.spoofing-leakage">Location Header Fields: Spoofing and Information Leakage</a></li>
     737               <li>12.4&nbsp;&nbsp;&nbsp;<a href="#rfc.section.12.4">Security Considerations for CONNECT</a></li>
     738               <li>12.5&nbsp;&nbsp;&nbsp;<a href="#privacy.issues.connected.to.accept.header.fields">Privacy Issues Connected to Accept Header Fields</a></li>
    746739            </ul>
    747740         </li>
    748          <li>12.&nbsp;&nbsp;&nbsp;<a href="#acks">Acknowledgments</a></li>
    749          <li>13.&nbsp;&nbsp;&nbsp;<a href="#rfc.references">References</a><ul>
    750                <li>13.1&nbsp;&nbsp;&nbsp;<a href="#rfc.references.1">Normative References</a></li>
    751                <li>13.2&nbsp;&nbsp;&nbsp;<a href="#rfc.references.2">Informative References</a></li>
     741         <li>13.&nbsp;&nbsp;&nbsp;<a href="#acks">Acknowledgments</a></li>
     742         <li>14.&nbsp;&nbsp;&nbsp;<a href="#rfc.references">References</a><ul>
     743               <li>14.1&nbsp;&nbsp;&nbsp;<a href="#rfc.references.1">Normative References</a></li>
     744               <li>14.2&nbsp;&nbsp;&nbsp;<a href="#rfc.references.2">Informative References</a></li>
    752745            </ul>
    753746         </li>
    … …  
    811804      </ul>
    812805      <h1 id="rfc.section.1" class="np"><a href="#rfc.section.1">1.</a>&nbsp;<a id="introduction" href="#introduction">Introduction</a></h1>
    813       <p id="rfc.section.1.p.1">This document defines HTTP/1.1 request and response semantics. Each HTTP message, as defined in <a href="#Part1" id="rfc.xref.Part1.1"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, is in the form of either a request or a response. An HTTP server listens on a connection for HTTP requests and responds
    814          to each request, in the order received on that connection, with one or more HTTP response messages. This document defines
    815          the commonly agreed upon semantics of the HTTP uniform interface, the intentions defined by each request method, and the various
    816          response messages that might be expected as a result of applying that method to the target resource.
    817       </p>
    818       <p id="rfc.section.1.p.2">Furthermore, it defines HTTP/1.1 message payloads (a.k.a., content), the associated metadata header fields that define how
    819          the payload is intended to be interpreted by a recipient, the request header fields that might influence content selection,
    820          and the various selection algorithms that are collectively referred to as HTTP content negotiation.
    821       </p>
    822       <p id="rfc.section.1.p.3">This document is currently disorganized in order to minimize the changes between drafts and enable reviewers to see the smaller
    823          errata changes. A future draft will reorganize the sections to better reflect the content. In particular, the sections will
    824          be ordered according to the typical processing of an HTTP request message (after message parsing): resource mapping, methods,
    825          request modifying header fields, response status, status modifying header fields, and resource metadata. The current mess
    826          reflects how widely dispersed these topics and associated requirements had become in <a href="#RFC2616" id="rfc.xref.RFC2616.1"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>.
    827       </p>
    828       <h2 id="rfc.section.1.1"><a href="#rfc.section.1.1">1.1</a>&nbsp;<a id="terminology" href="#terminology">Terminology</a></h2>
    829       <p id="rfc.section.1.1.p.1">This specification uses a number of terms to refer to the roles played by participants in, and objects of, the HTTP communication.</p>
    830       <p id="rfc.section.1.1.p.2"> <span id="rfc.iref.c.1"></span>  <dfn>content negotiation</dfn> 
    831       </p>
    832       <ul class="empty">
    833          <li>The mechanism for selecting the appropriate representation when servicing a request. The representation in any response can
    834             be negotiated (including error responses).
    835          </li>
    836       </ul>
    837       <p id="rfc.section.1.1.p.3"> <span id="rfc.iref.s.1"></span>  <dfn>selected representation</dfn> 
    838       </p>
    839       <ul class="empty">
    840          <li>The current representation of the target resource that would have been selected in a successful response if the same request
    841             had used the method GET and excluded any conditional request header fields.
    842          </li>
    843       </ul>
    844       <h2 id="rfc.section.1.2"><a href="#rfc.section.1.2">1.2</a>&nbsp;<a id="intro.conformance.and.error.handling" href="#intro.conformance.and.error.handling">Conformance and Error Handling</a></h2>
    845       <p id="rfc.section.1.2.p.1">The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL"
    846          in this document are to be interpreted as described in <a href="#RFC2119" id="rfc.xref.RFC2119.1"><cite title="Key words for use in RFCs to Indicate Requirement Levels">[RFC2119]</cite></a>.
    847       </p>
    848       <p id="rfc.section.1.2.p.2">This specification targets conformance criteria according to the role of a participant in HTTP communication. Hence, HTTP
    849          requirements are placed on senders, recipients, clients, servers, user agents, intermediaries, origin servers, proxies, gateways,
    850          or caches, depending on what behavior is being constrained by the requirement. See <a href="p1-messaging.html#architecture" title="Architecture">Section 2</a> of <a href="#Part1" id="rfc.xref.Part1.2"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for definitions of these terms.
    851       </p>
    852       <p id="rfc.section.1.2.p.3">The verb "generate" is used instead of "send" where a requirement differentiates between creating a protocol element and merely
    853          forwarding a received element downstream.
    854       </p>
    855       <p id="rfc.section.1.2.p.4">An implementation is considered conformant if it complies with all of the requirements associated with the roles it partakes
    856          in HTTP. Note that SHOULD-level requirements are relevant here, unless one of the documented exceptions is applicable.
    857       </p>
    858       <p id="rfc.section.1.2.p.5">This document also uses ABNF to define valid protocol elements (<a href="#notation" title="Syntax Notation">Section&nbsp;1.3</a>). In addition to the prose requirements placed upon them, senders <em class="bcp14">MUST NOT</em> generate protocol elements that do not match the grammar defined by the ABNF rules for those protocol elements that are applicable
    859          to the sender's role. If a received protocol element is processed, the recipient <em class="bcp14">MUST</em> be able to parse any value that would match the ABNF rules for that protocol element, excluding only those rules not applicable
    860          to the recipient's role.
    861       </p>
    862       <p id="rfc.section.1.2.p.6">Unless noted otherwise, a recipient <em class="bcp14">MAY</em> attempt to recover a usable protocol element from an invalid construct. HTTP does not define specific error handling mechanisms
    863          except when they have a direct impact on security, since different applications of the protocol require different error handling
    864          strategies. For example, a Web browser might wish to transparently recover from a response where the <a href="#header.location" class="smpl">Location</a> header field doesn't parse according to the ABNF, whereas a systems control client might consider any form of error recovery
    865          to be dangerous.
    866       </p>
    867       <h2 id="rfc.section.1.3"><a href="#rfc.section.1.3">1.3</a>&nbsp;<a id="notation" href="#notation">Syntax Notation</a></h2>
    868       <p id="rfc.section.1.3.p.1">This specification uses the Augmented Backus-Naur Form (ABNF) notation of <a href="#RFC5234" id="rfc.xref.RFC5234.1"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a> with the list rule extension defined in <a href="p1-messaging.html#notation" title="Syntax Notation">Section 1.2</a> of <a href="#Part1" id="rfc.xref.Part1.3"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. <a href="#collected.abnf" title="Collected ABNF">Appendix&nbsp;D</a> shows the collected ABNF with the list rule expanded.
    869       </p>
    870       <p id="rfc.section.1.3.p.2">The following core rules are included by reference, as defined in <a href="#RFC5234" id="rfc.xref.RFC5234.2"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a>, <a href="http://tools.ietf.org/html/rfc5234#appendix-B.1">Appendix B.1</a>: ALPHA (letters), CR (carriage return), CRLF (CR LF), CTL (controls), DIGIT (decimal 0-9), DQUOTE (double quote), HEXDIG
    871          (hexadecimal 0-9/A-F/a-f), HTAB (horizontal tab), LF (line feed), OCTET (any 8-bit sequence of data), SP (space), and VCHAR
    872          (any visible US-ASCII character).
    873       </p>
    874       <h3 id="rfc.section.1.3.1"><a href="#rfc.section.1.3.1">1.3.1</a>&nbsp;<a id="core.rules" href="#core.rules">Core Rules</a></h3>
    875       <p id="rfc.section.1.3.1.p.1">The core rules below are defined in <a href="#Part1" id="rfc.xref.Part1.4"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>:
    876       </p>
    877       <div id="rfc.figure.u.1"></div><pre class="inline">  <a href="#core.rules" class="smpl">BWS</a>           = &lt;BWS, defined in <a href="#Part1" id="rfc.xref.Part1.5"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
    878   <a href="#core.rules" class="smpl">OWS</a>           = &lt;OWS, defined in <a href="#Part1" id="rfc.xref.Part1.6"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
    879   <a href="#core.rules" class="smpl">RWS</a>           = &lt;RWS, defined in <a href="#Part1" id="rfc.xref.Part1.7"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
    880   <a href="#core.rules" class="smpl">quoted-string</a> = &lt;quoted-string, defined in <a href="#Part1" id="rfc.xref.Part1.8"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
    881   <a href="#core.rules" class="smpl">token</a>         = &lt;token, defined in <a href="#Part1" id="rfc.xref.Part1.9"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
    882   <a href="#core.rules" class="smpl">word</a>          = &lt;word, defined in <a href="#Part1" id="rfc.xref.Part1.10"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
    883 </pre><h3 id="rfc.section.1.3.2"><a href="#rfc.section.1.3.2">1.3.2</a>&nbsp;<a id="abnf.dependencies" href="#abnf.dependencies">ABNF Rules defined in other Parts of the Specification</a></h3>
    884       <p id="rfc.section.1.3.2.p.1">The ABNF rules below are defined in other parts:</p>
    885       <div id="rfc.figure.u.2"></div><pre class="inline">  <a href="#abnf.dependencies" class="smpl">absolute-URI</a>  = &lt;absolute-URI, defined in <a href="#Part1" id="rfc.xref.Part1.11"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.8</a>&gt;
    886   <a href="#abnf.dependencies" class="smpl">comment</a>       = &lt;comment, defined in <a href="#Part1" id="rfc.xref.Part1.12"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
    887   <a href="#abnf.dependencies" class="smpl">partial-URI</a>   = &lt;partial-URI, defined in <a href="#Part1" id="rfc.xref.Part1.13"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.8</a>&gt;
    888   <a href="#abnf.dependencies" class="smpl">qvalue</a>        = &lt;qvalue, defined in <a href="#Part1" id="rfc.xref.Part1.14"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#quality.values" title="Quality Values">Section 4.3.1</a>&gt;
    889   <a href="#abnf.dependencies" class="smpl">URI-reference</a> = &lt;URI-reference, defined in <a href="#Part1" id="rfc.xref.Part1.15"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.8</a>&gt;
    890 </pre><h1 id="rfc.section.2"><a href="#rfc.section.2">2.</a>&nbsp;<a id="methods" href="#methods">Methods</a></h1>
    891       <p id="rfc.section.2.p.1">The method token indicates the request method to be performed on the target resource (<a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.16"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). The method is case-sensitive.
    892       </p>
    893       <div id="rfc.figure.u.3"></div><pre class="inline"><span id="rfc.iref.g.1"></span>  <a href="#methods" class="smpl">method</a>         = <a href="#core.rules" class="smpl">token</a>
     806      <p id="rfc.section.1.p.1">This document defines HTTP/1.1 request and response semantics in terms of the architecture, syntax notation, and conformance
     807         criteria defined in <a href="p1-messaging.html#architecture" title="Architecture">Section 2</a> of <a href="#Part1" id="rfc.xref.Part1.1"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. Each HTTP message is either a request or a response. A server listens on a connection for a request, parses each message
     808         received, interprets the message semantics in relation to the identified request target, and responds to that request with
     809         one or more response messages.
     810      </p>
     811      <p id="rfc.section.1.p.2">HTTP provides a uniform interface for interacting with resources regardless of their type, nature, or implementation. HTTP
     812         semantics includes the intentions defined by each request method, extensions to those semantics that might be described in
     813         request header fields, the meaning of status codes to indicate a machine-readable response, and additional control data and
     814         resource metadata that might be given in response header fields.
     815      </p>
     816      <p id="rfc.section.1.p.3"><span id="rfc.iref.c.1"></span> In addition, this document defines the payload of messages (a.k.a., content), the associated metadata header fields that define
     817         how the payload is intended to be interpreted by a recipient, the request header fields that might influence content selection,
     818         and the various selection algorithms that are collectively referred to as "<dfn>content negotiation</dfn>".
     819      </p>
     820      <div class="note" id="rfc.section.1.p.4">
     821         <p>This document is currently disorganized in order to minimize the changes between drafts and enable reviewers to see the smaller
     822            errata changes. A future draft will reorganize the sections to better reflect the content. In particular, the sections will
     823            be ordered according to the typical processing of an HTTP request message (after message parsing): resource mapping, methods,
     824            request modifying header fields, response status, status modifying header fields, and resource metadata. The current mess
     825            reflects how widely dispersed these topics and associated requirements had become in <a href="#RFC2616" id="rfc.xref.RFC2616.1"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>.
     826         </p>
     827      </div>
     828      <h1 id="rfc.section.2"><a href="#rfc.section.2">2.</a>&nbsp;<a id="methods" href="#methods">Methods</a></h1>
     829      <p id="rfc.section.2.p.1">The method token indicates the request method to be performed on the target resource (<a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.2"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). The method is case-sensitive.
     830      </p>
     831      <div id="rfc.figure.u.1"></div><pre class="inline"><span id="rfc.iref.g.1"></span>  <a href="#methods" class="smpl">method</a>         = <a href="#abnf.dependencies" class="smpl">token</a>
    894832</pre><p id="rfc.section.2.p.3">The list of methods allowed by a resource can be specified in an <a href="#header.allow" class="smpl">Allow</a> header field (<a href="#header.allow" id="rfc.xref.header.allow.1" title="Allow">Section&nbsp;9.5</a>). The status code of the response always notifies the client whether a method is currently allowed on a resource, since the
    895833         set of allowed methods can change dynamically. An origin server <em class="bcp14">SHOULD</em> respond with the status code <a href="#status.405" class="smpl">405 (Method Not Allowed)</a> if the method is known by the origin server but not allowed for the resource, and <a href="#status.501" class="smpl">501 (Not
    … …  
    897835      </p>
    898836      <h2 id="rfc.section.2.1"><a href="#rfc.section.2.1">2.1</a>&nbsp;<a id="safe.and.idempotent" href="#safe.and.idempotent">Safe and Idempotent Methods</a></h2>
    899       <div id="rfc.iref.s.2"></div>
     837      <div id="rfc.iref.s.1"></div>
    900838      <h3 id="rfc.section.2.1.1"><a href="#rfc.section.2.1.1">2.1.1</a>&nbsp;<a id="safe.methods" href="#safe.methods">Safe Methods</a></h3>
    901839      <p id="rfc.section.2.1.1.p.1">Implementers need to be aware that the software represents the user in their interactions over the Internet, and need to allow
    … …  
    941879         to a single application, so that this is clear.
    942880      </p>
    943       <p id="rfc.section.2.2.1.p.3">Due to the parsing rules defined in <a href="p1-messaging.html#message.body" title="Message Body">Section 3.3</a> of <a href="#Part1" id="rfc.xref.Part1.17"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, definitions of HTTP methods cannot prohibit the presence of a message body on either the request or the response message
     881      <p id="rfc.section.2.2.1.p.3">Due to the parsing rules defined in <a href="p1-messaging.html#message.body" title="Message Body">Section 3.3</a> of <a href="#Part1" id="rfc.xref.Part1.3"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, definitions of HTTP methods cannot prohibit the presence of a message body on either the request or the response message
    944882         (with responses to HEAD requests being the single exception). Definitions of new methods cannot change this rule, but they
    945883         can specify that only zero-length bodies (as opposed to absent bodies) are allowed.
    … …  
    960898         body to make more detailed queries on the server.
    961899      </p>
    962       <p id="rfc.section.2.3.1.p.4">If the request-target (<a href="p1-messaging.html#request-target" title="Request Target">Section 5.3</a> of <a href="#Part1" id="rfc.xref.Part1.18"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) is an asterisk ("*"), the OPTIONS request is intended to apply to the server in general rather than to a specific resource.
     900      <p id="rfc.section.2.3.1.p.4">If the request-target (<a href="p1-messaging.html#request-target" title="Request Target">Section 5.3</a> of <a href="#Part1" id="rfc.xref.Part1.4"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) is an asterisk ("*"), the OPTIONS request is intended to apply to the server in general rather than to a specific resource.
    963901         Since a server's communication options typically depend on the resource, the "*" request is only useful as a "ping" or "no-op"
    964902         type of method; it does nothing beyond allowing the client to test the capabilities of the server. For example, this can be
    … …  
    992930      <p id="rfc.section.2.3.2.p.6">The response to a GET request is cacheable and <em class="bcp14">MAY</em> be used to satisfy subsequent GET and HEAD requests (see <a href="#Part6" id="rfc.xref.Part6.2"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
    993931      </p>
    994       <p id="rfc.section.2.3.2.p.7">See <a href="#encoding.sensitive.information.in.uris" title="Encoding Sensitive Information in URIs">Section&nbsp;11.2</a> for security considerations when used for forms.
     932      <p id="rfc.section.2.3.2.p.7">See <a href="#encoding.sensitive.information.in.uris" title="Encoding Sensitive Information in URIs">Section&nbsp;12.2</a> for security considerations when used for forms.
    995933      </p>
    996934      <h3 id="rfc.section.2.3.3"><a href="#rfc.section.2.3.3">2.3.3</a>&nbsp;<a id="HEAD" href="#HEAD">HEAD</a></h3>
    … …  
    11161054      </p>
    11171055      <p id="rfc.section.2.3.7.p.2">TRACE allows the client to see what is being received at the other end of the request chain and use that data for testing
    1118          or diagnostic information. The value of the <a href="p1-messaging.html#header.via" class="smpl">Via</a> header field (<a href="p1-messaging.html#header.via" title="Via">Section 6.2</a> of <a href="#Part1" id="rfc.xref.Part1.19"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) is of particular interest, since it acts as a trace of the request chain. Use of the <a href="#header.max-forwards" class="smpl">Max-Forwards</a> header field allows the client to limit the length of the request chain, which is useful for testing a chain of proxies forwarding
     1056         or diagnostic information. The value of the <a href="p1-messaging.html#header.via" class="smpl">Via</a> header field (<a href="p1-messaging.html#header.via" title="Via">Section 6.2</a> of <a href="#Part1" id="rfc.xref.Part1.5"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) is of particular interest, since it acts as a trace of the request chain. Use of the <a href="#header.max-forwards" class="smpl">Max-Forwards</a> header field allows the client to limit the length of the request chain, which is useful for testing a chain of proxies forwarding
    11191057         messages in an infinite loop.
    11201058      </p>
    1121       <p id="rfc.section.2.3.7.p.3">If the request is valid, the response <em class="bcp14">SHOULD</em> have a <a href="#header.content-type" class="smpl">Content-Type</a> of "message/http" (see <a href="p1-messaging.html#internet.media.type.message.http" title="Internet Media Type message/http">Section 7.3.1</a> of <a href="#Part1" id="rfc.xref.Part1.20"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) and contain a message body that encloses a copy of the entire request message. Responses to the TRACE method are not cacheable.
     1059      <p id="rfc.section.2.3.7.p.3">If the request is valid, the response <em class="bcp14">SHOULD</em> have a <a href="#header.content-type" class="smpl">Content-Type</a> of "message/http" (see <a href="p1-messaging.html#internet.media.type.message.http" title="Internet Media Type message/http">Section 7.3.1</a> of <a href="#Part1" id="rfc.xref.Part1.6"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) and contain a message body that encloses a copy of the entire request message. Responses to the TRACE method are not cacheable.
    11221060      </p>
    11231061      <div id="rfc.iref.c.2"></div>
    … …  
    11271065         its behavior to blind forwarding of packets until the connection is closed.
    11281066      </p>
    1129       <p id="rfc.section.2.3.8.p.2">When using CONNECT, the request-target <em class="bcp14">MUST</em> use the authority form (<a href="p1-messaging.html#request-target" title="Request Target">Section 5.3</a> of <a href="#Part1" id="rfc.xref.Part1.21"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>); i.e., the request-target consists of only the host name and port number of the tunnel destination, separated by a colon.
     1067      <p id="rfc.section.2.3.8.p.2">When using CONNECT, the request-target <em class="bcp14">MUST</em> use the authority form (<a href="p1-messaging.html#request-target" title="Request Target">Section 5.3</a> of <a href="#Part1" id="rfc.xref.Part1.7"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>); i.e., the request-target consists of only the host name and port number of the tunnel destination, separated by a colon.
    11301068         For example,
    11311069      </p>
    1132       <div id="rfc.figure.u.4"></div><pre class="text2">CONNECT server.example.com:80 HTTP/1.1
     1070      <div id="rfc.figure.u.2"></div><pre class="text2">CONNECT server.example.com:80 HTTP/1.1
    11331071Host: server.example.com:80
    11341072
    … …  
    11431081      </p>
    11441082      <p id="rfc.section.2.3.8.p.7">Proxy authentication might be used to establish the authority to create a tunnel:</p>
    1145       <div id="rfc.figure.u.5"></div><pre class="text2">CONNECT server.example.com:80 HTTP/1.1
     1083      <div id="rfc.figure.u.3"></div><pre class="text2">CONNECT server.example.com:80 HTTP/1.1
    11461084Host: server.example.com:80
    11471085Proxy-Authorization: basic aGVsbG86d29ybGQ=
    … …  
    11641102      <h1 id="rfc.section.3"><a href="#rfc.section.3">3.</a>&nbsp;<a id="header.fields" href="#header.fields">Header Fields</a></h1>
    11651103      <p id="rfc.section.3.p.1">Header fields are key value pairs that can be used to communicate data about the message, its payload, the target resource,
    1166          or about the connection itself (i.e., control data). See <a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a> of <a href="#Part1" id="rfc.xref.Part1.22"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for a general definition of their syntax.
     1104         or about the connection itself (i.e., control data). See <a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a> of <a href="#Part1" id="rfc.xref.Part1.8"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for a general definition of their syntax.
    11671105      </p>
    11681106      <h2 id="rfc.section.3.1"><a href="#rfc.section.3.1">3.1</a>&nbsp;<a id="considerations.for.creating.header.fields" href="#considerations.for.creating.header.fields">Considerations for Creating Header Fields</a></h2>
    … …  
    11721110         with "X-" if they are to be registered (either immediately or in the future).
    11731111      </p>
    1174       <p id="rfc.section.3.1.p.3">New header field values typically have their syntax defined using ABNF (<a href="#RFC5234" id="rfc.xref.RFC5234.3"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a>), using the extension defined in <a href="p1-messaging.html#abnf.extension" title="ABNF list extension: #rule">Section 3.2.5</a> of <a href="#Part1" id="rfc.xref.Part1.23"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> as necessary, and are usually constrained to the range of ASCII characters. Header fields needing a greater range of characters
     1112      <p id="rfc.section.3.1.p.3">New header field values typically have their syntax defined using ABNF (<a href="#RFC5234" id="rfc.xref.RFC5234.1"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a>), using the extension defined in <a href="p1-messaging.html#abnf.extension" title="ABNF list extension: #rule">Section 3.2.5</a> of <a href="#Part1" id="rfc.xref.Part1.9"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> as necessary, and are usually constrained to the range of ASCII characters. Header fields needing a greater range of characters
    11751113         can use an encoding such as the one defined in <a href="#RFC5987" id="rfc.xref.RFC5987.1"><cite title="Character Set and Language Encoding for Hypertext Transfer Protocol (HTTP) Header Field Parameters">[RFC5987]</cite></a>.
    11761114      </p>
    11771115      <p id="rfc.section.3.1.p.4">Because commas (",") are used as a generic delimiter between field-values, they need to be treated with care if they are allowed
    11781116         in the field-value's payload. Typically, components that might contain a comma are protected with double-quotes using the
    1179          quoted-string ABNF production (<a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a> of <a href="#Part1" id="rfc.xref.Part1.24"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
     1117         quoted-string ABNF production (<a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a> of <a href="#Part1" id="rfc.xref.Part1.10"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
    11801118      </p>
    11811119      <p id="rfc.section.3.1.p.5">For example, a textual date and a URI (either of which might contain a comma) could be safely carried in field-values like
    11821120         these:
    11831121      </p>
    1184       <div id="rfc.figure.u.6"></div><pre class="text">  Example-URI-Field: "http://example.com/a.html,foo",
     1122      <div id="rfc.figure.u.4"></div><pre class="text">  Example-URI-Field: "http://example.com/a.html,foo",
    11851123                     "http://without-a-comma.example.com/"
    11861124  Example-Date-Field: "Sat, 04 May 1996", "Wed, 14 Sep 2005"
    … …  
    11951133      <ul>
    11961134         <li>
    1197             <p>Whether the field is a single value, or whether it can be a list (delimited by commas; see <a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a> of <a href="#Part1" id="rfc.xref.Part1.25"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
     1135            <p>Whether the field is a single value, or whether it can be a list (delimited by commas; see <a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a> of <a href="#Part1" id="rfc.xref.Part1.11"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
    11981136            </p>
    11991137            <p>If it does not use the list syntax, document how to treat messages where the header field occurs multiple times (a sensible
    … …  
    12111149         </li>
    12121150         <li>
    1213             <p>Whether it is appropriate to list the field-name in the <a href="p1-messaging.html#header.connection" class="smpl">Connection</a> header field (i.e., if the header field is to be hop-by-hop, see <a href="p1-messaging.html#header.connection" title="Connection">Section 6.1</a> of <a href="#Part1" id="rfc.xref.Part1.26"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
     1151            <p>Whether it is appropriate to list the field-name in the <a href="p1-messaging.html#header.connection" class="smpl">Connection</a> header field (i.e., if the header field is to be hop-by-hop, see <a href="p1-messaging.html#header.connection" title="Connection">Section 6.1</a> of <a href="#Part1" id="rfc.xref.Part1.12"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
    12141152            </p>
    12151153         </li>
    … …  
    12221160         </li>
    12231161         <li>
    1224             <p>Whether the header field is useful or allowable in trailers (see <a href="p1-messaging.html#chunked.encoding" title="Chunked Transfer Coding">Section 4.1</a> of <a href="#Part1" id="rfc.xref.Part1.27"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
     1162            <p>Whether the header field is useful or allowable in trailers (see <a href="p1-messaging.html#chunked.encoding" title="Chunked Transfer Coding">Section 4.1</a> of <a href="#Part1" id="rfc.xref.Part1.13"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
    12251163            </p>
    12261164         </li>
    … …  
    12731211               <tr>
    12741212                  <td class="left">Host</td>
    1275                   <td class="left"><a href="p1-messaging.html#header.host" title="Host">Section 5.4</a> of <a href="#Part1" id="rfc.xref.Part1.28"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a></td>
     1213                  <td class="left"><a href="p1-messaging.html#header.host" title="Host">Section 5.4</a> of <a href="#Part1" id="rfc.xref.Part1.14"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a></td>
    12761214               </tr>
    12771215               <tr>
    … …  
    13131251               <tr>
    13141252                  <td class="left">TE</td>
    1315                   <td class="left"><a href="p1-messaging.html#header.te" title="TE">Section 4.3</a> of <a href="#Part1" id="rfc.xref.Part1.29"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a></td>
     1253                  <td class="left"><a href="p1-messaging.html#header.te" title="TE">Section 4.3</a> of <a href="#Part1" id="rfc.xref.Part1.15"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a></td>
    13161254               </tr>
    13171255               <tr>
    … …  
    13241262      <h2 id="rfc.section.3.3"><a href="#rfc.section.3.3">3.3</a>&nbsp;<a id="response.header.fields" href="#response.header.fields">Response Header Fields</a></h2>
    13251263      <p id="rfc.section.3.3.p.1">The response header fields allow the server to pass additional information about the response which cannot be placed in the
    1326          status-line. These header fields give information about the server and about further access to the target resource (<a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.30"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
     1264         status-line. These header fields give information about the server and about further access to the target resource (<a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.16"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
    13271265      </p>
    13281266      <div id="rfc.table.u.2">
    … …  
    16541592      </p>
    16551593      <h2 id="rfc.section.4.3"><a href="#rfc.section.4.3">4.3</a>&nbsp;<a id="status.1xx" href="#status.1xx">Informational 1xx</a></h2>
    1656       <div id="rfc.iref.21"></div>
    1657       <div id="rfc.iref.s.3"></div>
     1594      <div id="rfc.iref.20"></div>
     1595      <div id="rfc.iref.s.2"></div>
    16581596      <p id="rfc.section.4.3.p.1">This class of status code indicates a provisional response, consisting only of the status-line and optional header fields,
    16591597         and is terminated by an empty line. There are no required header fields for this class of status code. Since HTTP/1.0 did
    … …  
    16671605         a request, then it need not forward the corresponding <a href="#status.100" class="smpl">100 (Continue)</a> response(s).)
    16681606      </p>
    1669       <div id="rfc.iref.22"></div>
    1670       <div id="rfc.iref.s.4"></div>
     1607      <div id="rfc.iref.21"></div>
     1608      <div id="rfc.iref.s.3"></div>
    16711609      <h3 id="rfc.section.4.3.1"><a href="#rfc.section.4.3.1">4.3.1</a>&nbsp;<a id="status.100" href="#status.100">100 Continue</a></h3>
    16721610      <p id="rfc.section.4.3.1.p.1">The client <em class="bcp14">SHOULD</em> continue with its request. This interim response is used to inform the client that the initial part of the request has been
    16731611         received and has not yet been rejected by the server. The client <em class="bcp14">SHOULD</em> continue by sending the remainder of the request or, if the request has already been completed, ignore this response. The
    1674          server <em class="bcp14">MUST</em> send a final response after the request has been completed. See <a href="p1-messaging.html#use.of.the.100.status" title="Use of the 100 (Continue) Status">Section 6.4.3</a> of <a href="#Part1" id="rfc.xref.Part1.31"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for detailed discussion of the use and handling of this status code.
    1675       </p>
    1676       <div id="rfc.iref.23"></div>
    1677       <div id="rfc.iref.s.5"></div>
     1612         server <em class="bcp14">MUST</em> send a final response after the request has been completed. See <a href="p1-messaging.html#use.of.the.100.status" title="Use of the 100 (Continue) Status">Section 6.4.3</a> of <a href="#Part1" id="rfc.xref.Part1.17"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for detailed discussion of the use and handling of this status code.
     1613      </p>
     1614      <div id="rfc.iref.22"></div>
     1615      <div id="rfc.iref.s.4"></div>
    16781616      <h3 id="rfc.section.4.3.2"><a href="#rfc.section.4.3.2">4.3.2</a>&nbsp;<a id="status.101" href="#status.101">101 Switching Protocols</a></h3>
    1679       <p id="rfc.section.4.3.2.p.1">The server understands and is willing to comply with the client's request, via the <a href="p1-messaging.html#header.upgrade" class="smpl">Upgrade</a> message header field (<a href="p1-messaging.html#header.upgrade" title="Upgrade">Section 6.5</a> of <a href="#Part1" id="rfc.xref.Part1.32"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>), for a change in the application protocol being used on this connection. The server will switch protocols to those defined
     1617      <p id="rfc.section.4.3.2.p.1">The server understands and is willing to comply with the client's request, via the <a href="p1-messaging.html#header.upgrade" class="smpl">Upgrade</a> message header field (<a href="p1-messaging.html#header.upgrade" title="Upgrade">Section 6.5</a> of <a href="#Part1" id="rfc.xref.Part1.18"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>), for a change in the application protocol being used on this connection. The server will switch protocols to those defined
    16801618         by the response's Upgrade header field immediately after the empty line which terminates the 101 response.
    16811619      </p>
    … …  
    16851623      </p>
    16861624      <h2 id="rfc.section.4.4"><a href="#rfc.section.4.4">4.4</a>&nbsp;<a id="status.2xx" href="#status.2xx">Successful 2xx</a></h2>
     1625      <div id="rfc.iref.23"></div>
     1626      <div id="rfc.iref.s.5"></div>
     1627      <p id="rfc.section.4.4.p.1">This class of status code indicates that the client's request was successfully received, understood, and accepted.</p>
    16871628      <div id="rfc.iref.24"></div>
    16881629      <div id="rfc.iref.s.6"></div>
    1689       <p id="rfc.section.4.4.p.1">This class of status code indicates that the client's request was successfully received, understood, and accepted.</p>
    1690       <div id="rfc.iref.25"></div>
    1691       <div id="rfc.iref.s.7"></div>
    16921630      <h3 id="rfc.section.4.4.1"><a href="#rfc.section.4.4.1">4.4.1</a>&nbsp;<a id="status.200" href="#status.200">200 OK</a></h3>
    16931631      <p id="rfc.section.4.4.1.p.1">The request has succeeded. The payload returned with the response is dependent on the method used in the request, for example: </p>
    … …  
    17041642      <p id="rfc.section.4.4.1.p.2">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.11"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 200 responses.
    17051643      </p>
    1706       <div id="rfc.iref.26"></div>
    1707       <div id="rfc.iref.s.8"></div>
     1644      <div id="rfc.iref.25"></div>
     1645      <div id="rfc.iref.s.7"></div>
    17081646      <h3 id="rfc.section.4.4.2"><a href="#rfc.section.4.4.2">4.4.2</a>&nbsp;<a id="status.201" href="#status.201">201 Created</a></h3>
    17091647      <p id="rfc.section.4.4.2.p.1">The request has been fulfilled and has resulted in one or more new resources being created.</p>
    … …  
    17171655         the <a href="#header.location" class="smpl">Location</a> header field or, in case the Location header field was omitted, by the Effective Request URI (see <a href="p4-conditional.html#header.etag" title="ETag">Section 2.3</a> of <a href="#Part4" id="rfc.xref.Part4.10"><cite title="HTTP/1.1, part 4: Conditional Requests">[Part4]</cite></a>).
    17181656      </p>
    1719       <div id="rfc.iref.27"></div>
    1720       <div id="rfc.iref.s.9"></div>
     1657      <div id="rfc.iref.26"></div>
     1658      <div id="rfc.iref.s.8"></div>
    17211659      <h3 id="rfc.section.4.4.3"><a href="#rfc.section.4.4.3">4.4.3</a>&nbsp;<a id="status.202" href="#status.202">202 Accepted</a></h3>
    17221660      <p id="rfc.section.4.4.3.p.1">The request has been accepted for processing, but the processing has not been completed. The request might or might not eventually
    … …  
    17291667         user can expect the request to be fulfilled.
    17301668      </p>
     1669      <div id="rfc.iref.27"></div>
     1670      <div id="rfc.iref.s.9"></div>
     1671      <h3 id="rfc.section.4.4.4"><a href="#rfc.section.4.4.4">4.4.4</a>&nbsp;<a id="status.203" href="#status.203">203 Non-Authoritative Information</a></h3>
     1672      <p id="rfc.section.4.4.4.p.1">The representation in the response has been transformed or otherwise modified by a transforming proxy (<a href="p1-messaging.html#intermediaries" title="Intermediaries">Section 2.4</a> of <a href="#Part1" id="rfc.xref.Part1.19"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). Note that the behavior of transforming intermediaries is controlled by the no-transform Cache-Control directive (<a href="p6-cache.html#header.cache-control" title="Cache-Control">Section 7.2</a> of <a href="#Part6" id="rfc.xref.Part6.12"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
     1673      </p>
     1674      <p id="rfc.section.4.4.4.p.2">This status code is only appropriate when the response status code would have been <a href="#status.200" class="smpl">200 (OK)</a> otherwise. When the status code before transformation would have been different, the 214 Transformation Applied warn-code
     1675         (<a href="p6-cache.html#header.warning" title="Warning">Section 7.6</a> of <a href="#Part6" id="rfc.xref.Part6.13"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) is appropriate.
     1676      </p>
     1677      <p id="rfc.section.4.4.4.p.3">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.14"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 203 responses.
     1678      </p>
    17311679      <div id="rfc.iref.28"></div>
    17321680      <div id="rfc.iref.s.10"></div>
    1733       <h3 id="rfc.section.4.4.4"><a href="#rfc.section.4.4.4">4.4.4</a>&nbsp;<a id="status.203" href="#status.203">203 Non-Authoritative Information</a></h3>
    1734       <p id="rfc.section.4.4.4.p.1">The representation in the response has been transformed or otherwise modified by a transforming proxy (<a href="p1-messaging.html#intermediaries" title="Intermediaries">Section 2.4</a> of <a href="#Part1" id="rfc.xref.Part1.33"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). Note that the behavior of transforming intermediaries is controlled by the no-transform Cache-Control directive (<a href="p6-cache.html#header.cache-control" title="Cache-Control">Section 7.2</a> of <a href="#Part6" id="rfc.xref.Part6.12"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
    1735       </p>
    1736       <p id="rfc.section.4.4.4.p.2">This status code is only appropriate when the response status code would have been <a href="#status.200" class="smpl">200 (OK)</a> otherwise. When the status code before transformation would have been different, the 214 Transformation Applied warn-code
    1737          (<a href="p6-cache.html#header.warning" title="Warning">Section 7.6</a> of <a href="#Part6" id="rfc.xref.Part6.13"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) is appropriate.
    1738       </p>
    1739       <p id="rfc.section.4.4.4.p.3">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.14"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 203 responses.
    1740       </p>
    1741       <div id="rfc.iref.29"></div>
    1742       <div id="rfc.iref.s.11"></div>
    17431681      <h3 id="rfc.section.4.4.5"><a href="#rfc.section.4.4.5">4.4.5</a>&nbsp;<a id="status.204" href="#status.204">204 No Content</a></h3>
    17441682      <p id="rfc.section.4.4.5.p.1">The 204 (No Content) status code indicates that the server has successfully fulfilled the request and that there is no additional
    … …  
    17601698      <p id="rfc.section.4.4.5.p.5">The 204 response <em class="bcp14">MUST NOT</em> include a message body, and thus is always terminated by the first empty line after the header fields.
    17611699      </p>
    1762       <div id="rfc.iref.30"></div>
    1763       <div id="rfc.iref.s.12"></div>
     1700      <div id="rfc.iref.29"></div>
     1701      <div id="rfc.iref.s.11"></div>
    17641702      <h3 id="rfc.section.4.4.6"><a href="#rfc.section.4.4.6">4.4.6</a>&nbsp;<a id="status.205" href="#status.205">205 Reset Content</a></h3>
    17651703      <p id="rfc.section.4.4.6.p.1">The server has fulfilled the request and the user agent <em class="bcp14">SHOULD</em> reset the document view which caused the request to be sent. This response is primarily intended to allow input for actions
    … …  
    17671705         another input action.
    17681706      </p>
    1769       <p id="rfc.section.4.4.6.p.2">The message body included with the response <em class="bcp14">MUST</em> be empty. Note that receivers still need to parse the response according to the algorithm defined in <a href="p1-messaging.html#message.body" title="Message Body">Section 3.3</a> of <a href="#Part1" id="rfc.xref.Part1.34"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
     1707      <p id="rfc.section.4.4.6.p.2">The message body included with the response <em class="bcp14">MUST</em> be empty. Note that receivers still need to parse the response according to the algorithm defined in <a href="p1-messaging.html#message.body" title="Message Body">Section 3.3</a> of <a href="#Part1" id="rfc.xref.Part1.20"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
    17701708      </p>
    17711709      <h2 id="rfc.section.4.5"><a href="#rfc.section.4.5">4.5</a>&nbsp;<a id="status.3xx" href="#status.3xx">Redirection 3xx</a></h2>
    1772       <div id="rfc.iref.31"></div>
    1773       <div id="rfc.iref.s.13"></div>
     1710      <div id="rfc.iref.30"></div>
     1711      <div id="rfc.iref.s.12"></div>
    17741712      <p id="rfc.section.4.5.p.1">This class of status code indicates that further action needs to be taken by the user agent in order to fulfill the request.
    17751713         If the required action involves a subsequent HTTP request, it <em class="bcp14">MAY</em> be carried out by the user agent without interaction with the user if and only if the method used in the second request is
    … …  
    18161754         </p>
    18171755      </div>
    1818       <div id="rfc.iref.32"></div>
    1819       <div id="rfc.iref.s.14"></div>
     1756      <div id="rfc.iref.31"></div>
     1757      <div id="rfc.iref.s.13"></div>
    18201758      <h3 id="rfc.section.4.5.1"><a href="#rfc.section.4.5.1">4.5.1</a>&nbsp;<a id="status.300" href="#status.300">300 Multiple Choices</a></h3>
    18211759      <p id="rfc.section.4.5.1.p.1">The target resource has more than one representation, each with its own specific location, and agent-driven negotiation information
    … …  
    18311769      <p id="rfc.section.4.5.1.p.4">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.15"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 300 responses.
    18321770      </p>
    1833       <div id="rfc.iref.33"></div>
    1834       <div id="rfc.iref.s.15"></div>
     1771      <div id="rfc.iref.32"></div>
     1772      <div id="rfc.iref.s.14"></div>
    18351773      <h3 id="rfc.section.4.5.2"><a href="#rfc.section.4.5.2">4.5.2</a>&nbsp;<a id="status.301" href="#status.301">301 Moved Permanently</a></h3>
    18361774      <p id="rfc.section.4.5.2.p.1">The target resource has been assigned a new permanent URI and any future references to this resource <em class="bcp14">SHOULD</em> use one of the returned URIs. Clients with link editing capabilities ought to automatically re-link references to the effective
    … …  
    18421780      </p>
    18431781      <div class="note" id="rfc.section.4.5.2.p.4">
     1782         <p> <b>Note:</b> For historic reasons, user agents <em class="bcp14">MAY</em> change the request method from POST to GET for the subsequent request. If this behavior is undesired, status code <a href="#status.307" class="smpl">307 (Temporary Redirect)</a> can be used instead.
     1783         </p>
     1784      </div>
     1785      <div id="rfc.iref.33"></div>
     1786      <div id="rfc.iref.s.15"></div>
     1787      <h3 id="rfc.section.4.5.3"><a href="#rfc.section.4.5.3">4.5.3</a>&nbsp;<a id="status.302" href="#status.302">302 Found</a></h3>
     1788      <p id="rfc.section.4.5.3.p.1">The target resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client <em class="bcp14">SHOULD</em> continue to use the effective request URI for future requests.
     1789      </p>
     1790      <p id="rfc.section.4.5.3.p.2">The temporary URI <em class="bcp14">SHOULD</em> be given by the <a href="#header.location" class="smpl">Location</a> field in the response. A response payload can contain a short hypertext note with a hyperlink to the new URI(s).
     1791      </p>
     1792      <div class="note" id="rfc.section.4.5.3.p.3">
    18441793         <p> <b>Note:</b> For historic reasons, user agents <em class="bcp14">MAY</em> change the request method from POST to GET for the subsequent request. If this behavior is undesired, status code <a href="#status.307" class="smpl">307 (Temporary Redirect)</a> can be used instead.
    18451794         </p>
    … …  
    18471796      <div id="rfc.iref.34"></div>
    18481797      <div id="rfc.iref.s.16"></div>
    1849       <h3 id="rfc.section.4.5.3"><a href="#rfc.section.4.5.3">4.5.3</a>&nbsp;<a id="status.302" href="#status.302">302 Found</a></h3>
    1850       <p id="rfc.section.4.5.3.p.1">The target resource resides temporarily under a different URI. Since the redirection might be altered on occasion, the client <em class="bcp14">SHOULD</em> continue to use the effective request URI for future requests.
    1851       </p>
    1852       <p id="rfc.section.4.5.3.p.2">The temporary URI <em class="bcp14">SHOULD</em> be given by the <a href="#header.location" class="smpl">Location</a> field in the response. A response payload can contain a short hypertext note with a hyperlink to the new URI(s).
    1853       </p>
    1854       <div class="note" id="rfc.section.4.5.3.p.3">
    1855          <p> <b>Note:</b> For historic reasons, user agents <em class="bcp14">MAY</em> change the request method from POST to GET for the subsequent request. If this behavior is undesired, status code <a href="#status.307" class="smpl">307 (Temporary Redirect)</a> can be used instead.
    1856          </p>
    1857       </div>
    1858       <div id="rfc.iref.35"></div>
    1859       <div id="rfc.iref.s.17"></div>
    18601798      <h3 id="rfc.section.4.5.4"><a href="#rfc.section.4.5.4">4.5.4</a>&nbsp;<a id="status.303" href="#status.303">303 See Other</a></h3>
    18611799      <p id="rfc.section.4.5.4.p.1">The 303 status code indicates that the server is redirecting the user agent to a different resource, as indicated by a URI
    … …  
    18771815      <p id="rfc.section.4.5.4.p.4">Except for responses to a HEAD request, the representation of a 303 response <em class="bcp14">SHOULD</em> contain a short hypertext note with a hyperlink to the <a href="#header.location" class="smpl">Location</a> URI.
    18781816      </p>
     1817      <div id="rfc.iref.35"></div>
     1818      <div id="rfc.iref.s.17"></div>
     1819      <h3 id="rfc.section.4.5.5"><a href="#rfc.section.4.5.5">4.5.5</a>&nbsp;<a id="status.305" href="#status.305">305 Use Proxy</a></h3>
     1820      <p id="rfc.section.4.5.5.p.1">The 305 status code was defined in a previous version of this specification (see <a href="#changes.from.rfc.2616" title="Changes from RFC 2616">Appendix&nbsp;C</a>), and is now deprecated.
     1821      </p>
    18791822      <div id="rfc.iref.36"></div>
    18801823      <div id="rfc.iref.s.18"></div>
    1881       <h3 id="rfc.section.4.5.5"><a href="#rfc.section.4.5.5">4.5.5</a>&nbsp;<a id="status.305" href="#status.305">305 Use Proxy</a></h3>
    1882       <p id="rfc.section.4.5.5.p.1">The 305 status code was defined in a previous version of this specification (see <a href="#changes.from.rfc.2616" title="Changes from RFC 2616">Appendix&nbsp;C</a>), and is now deprecated.
    1883       </p>
     1824      <h3 id="rfc.section.4.5.6"><a href="#rfc.section.4.5.6">4.5.6</a>&nbsp;<a id="status.306" href="#status.306">306 (Unused)</a></h3>
     1825      <p id="rfc.section.4.5.6.p.1">The 306 status code was used in a previous version of the specification, is no longer used, and the code is reserved.</p>
    18841826      <div id="rfc.iref.37"></div>
    18851827      <div id="rfc.iref.s.19"></div>
    1886       <h3 id="rfc.section.4.5.6"><a href="#rfc.section.4.5.6">4.5.6</a>&nbsp;<a id="status.306" href="#status.306">306 (Unused)</a></h3>
    1887       <p id="rfc.section.4.5.6.p.1">The 306 status code was used in a previous version of the specification, is no longer used, and the code is reserved.</p>
    1888       <div id="rfc.iref.38"></div>
    1889       <div id="rfc.iref.s.20"></div>
    18901828      <h3 id="rfc.section.4.5.7"><a href="#rfc.section.4.5.7">4.5.7</a>&nbsp;<a id="status.307" href="#status.307">307 Temporary Redirect</a></h3>
    18911829      <p id="rfc.section.4.5.7.p.1">The target resource resides temporarily under a different URI. Since the redirection can change over time, the client <em class="bcp14">SHOULD</em> continue to use the effective request URI for future requests.
    … …  
    19001838      </div>
    19011839      <h2 id="rfc.section.4.6"><a href="#rfc.section.4.6">4.6</a>&nbsp;<a id="status.4xx" href="#status.4xx">Client Error 4xx</a></h2>
    1902       <div id="rfc.iref.39"></div>
    1903       <div id="rfc.iref.s.21"></div>
     1840      <div id="rfc.iref.38"></div>
     1841      <div id="rfc.iref.s.20"></div>
    19041842      <p id="rfc.section.4.6.p.1">The 4xx class of status code is intended for cases in which the client seems to have erred. Except when responding to a HEAD
    19051843         request, the server <em class="bcp14">SHOULD</em> include a representation containing an explanation of the error situation, and whether it is a temporary or permanent condition.
    19061844         These status codes are applicable to any request method. User agents <em class="bcp14">SHOULD</em> display any included representation to the user.
    19071845      </p>
     1846      <div id="rfc.iref.39"></div>
     1847      <div id="rfc.iref.s.21"></div>
     1848      <h3 id="rfc.section.4.6.1"><a href="#rfc.section.4.6.1">4.6.1</a>&nbsp;<a id="status.400" href="#status.400">400 Bad Request</a></h3>
     1849      <p id="rfc.section.4.6.1.p.1">The server cannot or will not process the request, due to a client error (e.g., malformed syntax).</p>
    19081850      <div id="rfc.iref.40"></div>
    19091851      <div id="rfc.iref.s.22"></div>
    1910       <h3 id="rfc.section.4.6.1"><a href="#rfc.section.4.6.1">4.6.1</a>&nbsp;<a id="status.400" href="#status.400">400 Bad Request</a></h3>
    1911       <p id="rfc.section.4.6.1.p.1">The server cannot or will not process the request, due to a client error (e.g., malformed syntax).</p>
     1852      <h3 id="rfc.section.4.6.2"><a href="#rfc.section.4.6.2">4.6.2</a>&nbsp;<a id="status.402" href="#status.402">402 Payment Required</a></h3>
     1853      <p id="rfc.section.4.6.2.p.1">This code is reserved for future use.</p>
    19121854      <div id="rfc.iref.41"></div>
    19131855      <div id="rfc.iref.s.23"></div>
    1914       <h3 id="rfc.section.4.6.2"><a href="#rfc.section.4.6.2">4.6.2</a>&nbsp;<a id="status.402" href="#status.402">402 Payment Required</a></h3>
    1915       <p id="rfc.section.4.6.2.p.1">This code is reserved for future use.</p>
    1916       <div id="rfc.iref.42"></div>
    1917       <div id="rfc.iref.s.24"></div>
    19181856      <h3 id="rfc.section.4.6.3"><a href="#rfc.section.4.6.3">4.6.3</a>&nbsp;<a id="status.403" href="#status.403">403 Forbidden</a></h3>
    19191857      <p id="rfc.section.4.6.3.p.1">The server understood the request, but refuses to authorize it. Providing different user authentication credentials might
    … …  
    19241862            (Not Found)</a>  <em class="bcp14">MAY</em> be used instead.
    19251863      </p>
    1926       <div id="rfc.iref.43"></div>
    1927       <div id="rfc.iref.s.25"></div>
     1864      <div id="rfc.iref.42"></div>
     1865      <div id="rfc.iref.s.24"></div>
    19281866      <h3 id="rfc.section.4.6.4"><a href="#rfc.section.4.6.4">4.6.4</a>&nbsp;<a id="status.404" href="#status.404">404 Not Found</a></h3>
    19291867      <p id="rfc.section.4.6.4.p.1">The server has not found anything matching the effective request URI. No indication is given of whether the condition is temporary
    … …  
    19321870         has been refused, or when no other response is applicable.
    19331871      </p>
     1872      <div id="rfc.iref.43"></div>
     1873      <div id="rfc.iref.s.25"></div>
     1874      <h3 id="rfc.section.4.6.5"><a href="#rfc.section.4.6.5">4.6.5</a>&nbsp;<a id="status.405" href="#status.405">405 Method Not Allowed</a></h3>
     1875      <p id="rfc.section.4.6.5.p.1">The method specified in the request-line is not allowed for the target resource. The response <em class="bcp14">MUST</em> include an <a href="#header.allow" class="smpl">Allow</a> header field containing a list of valid methods for the requested resource.
     1876      </p>
    19341877      <div id="rfc.iref.44"></div>
    19351878      <div id="rfc.iref.s.26"></div>
    1936       <h3 id="rfc.section.4.6.5"><a href="#rfc.section.4.6.5">4.6.5</a>&nbsp;<a id="status.405" href="#status.405">405 Method Not Allowed</a></h3>
    1937       <p id="rfc.section.4.6.5.p.1">The method specified in the request-line is not allowed for the target resource. The response <em class="bcp14">MUST</em> include an <a href="#header.allow" class="smpl">Allow</a> header field containing a list of valid methods for the requested resource.
    1938       </p>
    1939       <div id="rfc.iref.45"></div>
    1940       <div id="rfc.iref.s.27"></div>
    19411879      <h3 id="rfc.section.4.6.6"><a href="#rfc.section.4.6.6">4.6.6</a>&nbsp;<a id="status.406" href="#status.406">406 Not Acceptable</a></h3>
    19421880      <p id="rfc.section.4.6.6.p.1">The resource identified by the request is only capable of generating response representations which have content characteristics
    … …  
    19551893      <p id="rfc.section.4.6.6.p.4">If the response could be unacceptable, a user agent <em class="bcp14">SHOULD</em> temporarily stop receipt of more data and query the user for a decision on further actions.
    19561894      </p>
     1895      <div id="rfc.iref.45"></div>
     1896      <div id="rfc.iref.s.27"></div>
     1897      <h3 id="rfc.section.4.6.7"><a href="#rfc.section.4.6.7">4.6.7</a>&nbsp;<a id="status.408" href="#status.408">408 Request Timeout</a></h3>
     1898      <p id="rfc.section.4.6.7.p.1">The client did not produce a request within the time that the server was prepared to wait. The client <em class="bcp14">MAY</em> repeat the request without modifications at any later time.
     1899      </p>
    19571900      <div id="rfc.iref.46"></div>
    19581901      <div id="rfc.iref.s.28"></div>
    1959       <h3 id="rfc.section.4.6.7"><a href="#rfc.section.4.6.7">4.6.7</a>&nbsp;<a id="status.408" href="#status.408">408 Request Timeout</a></h3>
    1960       <p id="rfc.section.4.6.7.p.1">The client did not produce a request within the time that the server was prepared to wait. The client <em class="bcp14">MAY</em> repeat the request without modifications at any later time.
    1961       </p>
    1962       <div id="rfc.iref.47"></div>
    1963       <div id="rfc.iref.s.29"></div>
    19641902      <h3 id="rfc.section.4.6.8"><a href="#rfc.section.4.6.8">4.6.8</a>&nbsp;<a id="status.409" href="#status.409">409 Conflict</a></h3>
    19651903      <p id="rfc.section.4.6.8.p.1">The request could not be completed due to a conflict with the current state of the resource. This code is only allowed in
    … …  
    19731911         contain a list of the differences between the two versions.
    19741912      </p>
    1975       <div id="rfc.iref.48"></div>
    1976       <div id="rfc.iref.s.30"></div>
     1913      <div id="rfc.iref.47"></div>
     1914      <div id="rfc.iref.s.29"></div>
    19771915      <h3 id="rfc.section.4.6.9"><a href="#rfc.section.4.6.9">4.6.9</a>&nbsp;<a id="status.410" href="#status.410">410 Gone</a></h3>
    19781916      <p id="rfc.section.4.6.9.p.1">The target resource is no longer available at the server and no forwarding address is known. This condition is expected to
    … …  
    19881926      <p id="rfc.section.4.6.9.p.3">Caches <em class="bcp14">MAY</em> use a heuristic (see <a href="p6-cache.html#heuristic.freshness" title="Calculating Heuristic Freshness">Section 4.1.2</a> of <a href="#Part6" id="rfc.xref.Part6.17"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) to determine freshness for 410 responses.
    19891927      </p>
    1990       <div id="rfc.iref.49"></div>
    1991       <div id="rfc.iref.s.31"></div>
     1928      <div id="rfc.iref.48"></div>
     1929      <div id="rfc.iref.s.30"></div>
    19921930      <h3 id="rfc.section.4.6.10"><a href="#rfc.section.4.6.10">4.6.10</a>&nbsp;<a id="status.411" href="#status.411">411 Length Required</a></h3>
    19931931      <p id="rfc.section.4.6.10.p.1">The server refuses to accept the request without a defined <a href="p1-messaging.html#header.content-length" class="smpl">Content-Length</a>. The client <em class="bcp14">MAY</em> repeat the request if it adds a valid Content-Length header field containing the length of the message body in the request
    19941932         message.
    19951933      </p>
    1996       <div id="rfc.iref.50"></div>
    1997       <div id="rfc.iref.s.32"></div>
     1934      <div id="rfc.iref.49"></div>
     1935      <div id="rfc.iref.s.31"></div>
    19981936      <h3 id="rfc.section.4.6.11"><a href="#rfc.section.4.6.11">4.6.11</a>&nbsp;<a id="status.413" href="#status.413">413 Request Representation Too Large</a></h3>
    19991937      <p id="rfc.section.4.6.11.p.1">The server is refusing to process a request because the request representation is larger than the server is willing or able
    … …  
    20021940      <p id="rfc.section.4.6.11.p.2">If the condition is temporary, the server <em class="bcp14">SHOULD</em> include a <a href="#header.retry-after" class="smpl">Retry-After</a> header field to indicate that it is temporary and after what time the client <em class="bcp14">MAY</em> try again.
    20031941      </p>
    2004       <div id="rfc.iref.51"></div>
    2005       <div id="rfc.iref.s.33"></div>
     1942      <div id="rfc.iref.50"></div>
     1943      <div id="rfc.iref.s.32"></div>
    20061944      <h3 id="rfc.section.4.6.12"><a href="#rfc.section.4.6.12">4.6.12</a>&nbsp;<a id="status.414" href="#status.414">414 URI Too Long</a></h3>
    20071945      <p id="rfc.section.4.6.12.p.1">The server is refusing to service the request because the effective request URI is longer than the server is willing to interpret.
    … …  
    20111949         in some servers using fixed-length buffers for reading or manipulating the request-target.
    20121950      </p>
    2013       <div id="rfc.iref.52"></div>
    2014       <div id="rfc.iref.s.34"></div>
     1951      <div id="rfc.iref.51"></div>
     1952      <div id="rfc.iref.s.33"></div>
    20151953      <h3 id="rfc.section.4.6.13"><a href="#rfc.section.4.6.13">4.6.13</a>&nbsp;<a id="status.415" href="#status.415">415 Unsupported Media Type</a></h3>
    20161954      <p id="rfc.section.4.6.13.p.1">The server is refusing to service the request because the request payload is in a format not supported by this request method
    20171955         on the target resource.
    20181956      </p>
    2019       <div id="rfc.iref.53"></div>
    2020       <div id="rfc.iref.s.35"></div>
     1957      <div id="rfc.iref.52"></div>
     1958      <div id="rfc.iref.s.34"></div>
    20211959      <h3 id="rfc.section.4.6.14"><a href="#rfc.section.4.6.14">4.6.14</a>&nbsp;<a id="status.417" href="#status.417">417 Expectation Failed</a></h3>
    20221960      <p id="rfc.section.4.6.14.p.1">The expectation given in an <a href="#header.expect" class="smpl">Expect</a> header field (see <a href="#header.expect" id="rfc.xref.header.expect.2" title="Expect">Section&nbsp;9.11</a>) could not be met by this server, or, if the server is a proxy, the server has unambiguous evidence that the request could
    20231961         not be met by the next-hop server.
    20241962      </p>
    2025       <div id="rfc.iref.54"></div>
    2026       <div id="rfc.iref.s.36"></div>
     1963      <div id="rfc.iref.53"></div>
     1964      <div id="rfc.iref.s.35"></div>
    20271965      <h3 id="rfc.section.4.6.15"><a href="#rfc.section.4.6.15">4.6.15</a>&nbsp;<a id="status.426" href="#status.426">426 Upgrade Required</a></h3>
    2028       <p id="rfc.section.4.6.15.p.1">The request can not be completed without a prior protocol upgrade. This response <em class="bcp14">MUST</em> include an <a href="p1-messaging.html#header.upgrade" class="smpl">Upgrade</a> header field (<a href="p1-messaging.html#header.upgrade" title="Upgrade">Section 6.5</a> of <a href="#Part1" id="rfc.xref.Part1.35"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) specifying the required protocols.
    2029       </p>
    2030       <div id="rfc.figure.u.7"></div>
     1966      <p id="rfc.section.4.6.15.p.1">The request can not be completed without a prior protocol upgrade. This response <em class="bcp14">MUST</em> include an <a href="p1-messaging.html#header.upgrade" class="smpl">Upgrade</a> header field (<a href="p1-messaging.html#header.upgrade" title="Upgrade">Section 6.5</a> of <a href="#Part1" id="rfc.xref.Part1.21"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) specifying the required protocols.
     1967      </p>
     1968      <div id="rfc.figure.u.5"></div>
    20311969      <p>Example:</p>  <pre class="text">HTTP/1.1 426 Upgrade Required
    20321970Upgrade: HTTP/3.0
    … …  
    20401978      </p>
    20411979      <h2 id="rfc.section.4.7"><a href="#rfc.section.4.7">4.7</a>&nbsp;<a id="status.5xx" href="#status.5xx">Server Error 5xx</a></h2>
    2042       <div id="rfc.iref.55"></div>
    2043       <div id="rfc.iref.s.37"></div>
     1980      <div id="rfc.iref.54"></div>
     1981      <div id="rfc.iref.s.36"></div>
    20441982      <p id="rfc.section.4.7.p.1">Response status codes beginning with the digit "5" indicate cases in which the server is aware that it has erred or is incapable
    20451983         of performing the request. Except when responding to a HEAD request, the server <em class="bcp14">SHOULD</em> include a representation containing an explanation of the error situation, and whether it is a temporary or permanent condition.
    20461984         User agents <em class="bcp14">SHOULD</em> display any included representation to the user. These response codes are applicable to any request method.
    20471985      </p>
     1986      <div id="rfc.iref.55"></div>
     1987      <div id="rfc.iref.s.37"></div>
     1988      <h3 id="rfc.section.4.7.1"><a href="#rfc.section.4.7.1">4.7.1</a>&nbsp;<a id="status.500" href="#status.500">500 Internal Server Error</a></h3>
     1989      <p id="rfc.section.4.7.1.p.1">The server encountered an unexpected condition which prevented it from fulfilling the request.</p>
    20481990      <div id="rfc.iref.56"></div>
    20491991      <div id="rfc.iref.s.38"></div>
    2050       <h3 id="rfc.section.4.7.1"><a href="#rfc.section.4.7.1">4.7.1</a>&nbsp;<a id="status.500" href="#status.500">500 Internal Server Error</a></h3>
    2051       <p id="rfc.section.4.7.1.p.1">The server encountered an unexpected condition which prevented it from fulfilling the request.</p>
    2052       <div id="rfc.iref.57"></div>
    2053       <div id="rfc.iref.s.39"></div>
    20541992      <h3 id="rfc.section.4.7.2"><a href="#rfc.section.4.7.2">4.7.2</a>&nbsp;<a id="status.501" href="#status.501">501 Not Implemented</a></h3>
    20551993      <p id="rfc.section.4.7.2.p.1">The server does not support the functionality required to fulfill the request. This is the appropriate response when the server
    20561994         does not recognize the request method and is not capable of supporting it for any resource.
    20571995      </p>
    2058       <div id="rfc.iref.58"></div>
    2059       <div id="rfc.iref.s.40"></div>
     1996      <div id="rfc.iref.57"></div>
     1997      <div id="rfc.iref.s.39"></div>
    20601998      <h3 id="rfc.section.4.7.3"><a href="#rfc.section.4.7.3">4.7.3</a>&nbsp;<a id="status.502" href="#status.502">502 Bad Gateway</a></h3>
    20611999      <p id="rfc.section.4.7.3.p.1">The server, while acting as a gateway or proxy, received an invalid response from the upstream server it accessed in attempting
    20622000         to fulfill the request.
    20632001      </p>
    2064       <div id="rfc.iref.59"></div>
    2065       <div id="rfc.iref.s.41"></div>
     2002      <div id="rfc.iref.58"></div>
     2003      <div id="rfc.iref.s.40"></div>
    20662004      <h3 id="rfc.section.4.7.4"><a href="#rfc.section.4.7.4">4.7.4</a>&nbsp;<a id="status.503" href="#status.503">503 Service Unavailable</a></h3>
    20672005      <p id="rfc.section.4.7.4.p.1">The server is currently unable to handle the request due to a temporary overloading or maintenance of the server.</p>
    … …  
    20752013         </p>
    20762014      </div>
    2077       <div id="rfc.iref.60"></div>
    2078       <div id="rfc.iref.s.42"></div>
     2015      <div id="rfc.iref.59"></div>
     2016      <div id="rfc.iref.s.41"></div>
    20792017      <h3 id="rfc.section.4.7.5"><a href="#rfc.section.4.7.5">4.7.5</a>&nbsp;<a id="status.504" href="#status.504">504 Gateway Timeout</a></h3>
    20802018      <p id="rfc.section.4.7.5.p.1">The server, while acting as a gateway or proxy, did not receive a timely response from the upstream server specified by the
    … …  
    20862024         </p>
    20872025      </div>
    2088       <div id="rfc.iref.61"></div>
    2089       <div id="rfc.iref.s.43"></div>
     2026      <div id="rfc.iref.60"></div>
     2027      <div id="rfc.iref.s.42"></div>
    20902028      <h3 id="rfc.section.4.7.6"><a href="#rfc.section.4.7.6">4.7.6</a>&nbsp;<a id="status.505" href="#status.505">505 HTTP Version Not Supported</a></h3>
    20912029      <p id="rfc.section.4.7.6.p.1">The server does not support, or refuses to support, the protocol version that was used in the request message. The server
    20922030         is indicating that it is unable or unwilling to complete the request using the same major version as the client, as described
    2093          in <a href="p1-messaging.html#http.version" title="Protocol Versioning">Section 2.7</a> of <a href="#Part1" id="rfc.xref.Part1.36"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, other than with this error message. The response <em class="bcp14">SHOULD</em> contain a representation describing why that version is not supported and what other protocols are supported by that server.
     2031         in <a href="p1-messaging.html#http.version" title="Protocol Versioning">Section 2.7</a> of <a href="#Part1" id="rfc.xref.Part1.22"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, other than with this error message. The response <em class="bcp14">SHOULD</em> contain a representation describing why that version is not supported and what other protocols are supported by that server.
    20942032      </p>
    20952033      <h1 id="rfc.section.5"><a href="#rfc.section.5">5.</a>&nbsp;<a id="protocol.parameters" href="#protocol.parameters">Protocol Parameters</a></h1>
    … …  
    20982036         a fixed-length subset of that defined by <a href="#RFC1123" id="rfc.xref.RFC1123.1"><cite title="Requirements for Internet Hosts - Application and Support">[RFC1123]</cite></a>:
    20992037      </p>
    2100       <div id="rfc.figure.u.8"></div><pre class="text">Sun, 06 Nov 1994 08:49:37 GMT  ; RFC 1123
     2038      <div id="rfc.figure.u.6"></div><pre class="text">Sun, 06 Nov 1994 08:49:37 GMT  ; RFC 1123
    21012039</pre><p id="rfc.section.5.1.p.3">The other formats are described here only for compatibility with obsolete implementations.</p>
    2102       <div id="rfc.figure.u.9"></div><pre class="text">Sunday, 06-Nov-94 08:49:37 GMT ; obsolete RFC 850 format
     2040      <div id="rfc.figure.u.7"></div><pre class="text">Sunday, 06-Nov-94 08:49:37 GMT ; obsolete RFC 850 format
    21032041Sun Nov  6 08:49:37 1994       ; ANSI C's asctime() format
    21042042</pre><p id="rfc.section.5.1.p.5">HTTP/1.1 clients and servers that parse a date value <em class="bcp14">MUST</em> accept all three formats (for compatibility with HTTP/1.0), though they <em class="bcp14">MUST</em> only generate the RFC 1123 format for representing HTTP-date values in header fields.
    … …  
    21082046         time zone, and <em class="bcp14">MUST</em> be assumed when reading the asctime format. HTTP-date is case sensitive and <em class="bcp14">MUST NOT</em> include additional whitespace beyond that specifically included as SP in the grammar.
    21092047      </p>
    2110       <div id="rfc.figure.u.10"></div><pre class="inline"><span id="rfc.iref.g.3"></span>  <a href="#http.date" class="smpl">HTTP-date</a>    = <a href="#preferred.date.format" class="smpl">rfc1123-date</a> / <a href="#obsolete.date.formats" class="smpl">obs-date</a>
     2048      <div id="rfc.figure.u.8"></div><pre class="inline"><span id="rfc.iref.g.3"></span>  <a href="#http.date" class="smpl">HTTP-date</a>    = <a href="#preferred.date.format" class="smpl">rfc1123-date</a> / <a href="#obsolete.date.formats" class="smpl">obs-date</a>
    21112049</pre><div id="preferred.date.format">
    21122050         <p id="rfc.section.5.1.p.8">                    Preferred format:</p>
    21132051      </div>
    2114       <div id="rfc.figure.u.11"></div><pre class="inline"><span id="rfc.iref.g.4"></span><span id="rfc.iref.g.5"></span><span id="rfc.iref.g.6"></span><span id="rfc.iref.g.7"></span><span id="rfc.iref.g.8"></span><span id="rfc.iref.g.9"></span><span id="rfc.iref.g.10"></span><span id="rfc.iref.g.11"></span><span id="rfc.iref.g.12"></span><span id="rfc.iref.g.13"></span><span id="rfc.iref.g.14"></span><span id="rfc.iref.g.15"></span>  <a href="#preferred.date.format" class="smpl">rfc1123-date</a> = <a href="#preferred.date.format" class="smpl">day-name</a> "," <a href="#notation" class="smpl">SP</a> date1 <a href="#notation" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#notation" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">GMT</a>
     2052      <div id="rfc.figure.u.9"></div><pre class="inline"><span id="rfc.iref.g.4"></span><span id="rfc.iref.g.5"></span><span id="rfc.iref.g.6"></span><span id="rfc.iref.g.7"></span><span id="rfc.iref.g.8"></span><span id="rfc.iref.g.9"></span><span id="rfc.iref.g.10"></span><span id="rfc.iref.g.11"></span><span id="rfc.iref.g.12"></span><span id="rfc.iref.g.13"></span><span id="rfc.iref.g.14"></span><span id="rfc.iref.g.15"></span>  <a href="#preferred.date.format" class="smpl">rfc1123-date</a> = <a href="#preferred.date.format" class="smpl">day-name</a> "," <a href="#abnf.dependencies" class="smpl">SP</a> date1 <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">GMT</a>
    21152053  ; fixed length subset of the format defined in
    21162054  ; <a href="http://tools.ietf.org/html/rfc1123#section-5.2.14">Section 5.2.14</a> of <a href="#RFC1123" id="rfc.xref.RFC1123.2"><cite title="Requirements for Internet Hosts - Application and Support">[RFC1123]</cite></a>
    … …  
    21242062               / %x53.75.6E ; "Sun", case-sensitive
    21252063               
    2126   <a href="#obsolete.date.formats" class="smpl">date1</a>        = <a href="#preferred.date.format" class="smpl">day</a> <a href="#notation" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">month</a> <a href="#notation" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">year</a>
     2064  <a href="#obsolete.date.formats" class="smpl">date1</a>        = <a href="#preferred.date.format" class="smpl">day</a> <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">month</a> <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">year</a>
    21272065               ; e.g., 02 Jun 1982
    21282066
    2129   <a href="#preferred.date.format" class="smpl">day</a>          = 2<a href="#notation" class="smpl">DIGIT</a>
     2067  <a href="#preferred.date.format" class="smpl">day</a>          = 2<a href="#abnf.dependencies" class="smpl">DIGIT</a>
    21302068  <a href="#preferred.date.format" class="smpl">month</a>        = %x4A.61.6E ; "Jan", case-sensitive
    21312069               / %x46.65.62 ; "Feb", case-sensitive
    … …  
    21402078               / %x4E.6F.76 ; "Nov", case-sensitive
    21412079               / %x44.65.63 ; "Dec", case-sensitive
    2142   <a href="#preferred.date.format" class="smpl">year</a>         = 4<a href="#notation" class="smpl">DIGIT</a>
     2080  <a href="#preferred.date.format" class="smpl">year</a>         = 4<a href="#abnf.dependencies" class="smpl">DIGIT</a>
    21432081
    21442082  <a href="#preferred.date.format" class="smpl">GMT</a>   = %x47.4D.54 ; "GMT", case-sensitive
    … …  
    21472085                 ; 00:00:00 - 23:59:59
    21482086                 
    2149   <a href="#preferred.date.format" class="smpl">hour</a>         = 2<a href="#notation" class="smpl">DIGIT</a>               
    2150   <a href="#preferred.date.format" class="smpl">minute</a>       = 2<a href="#notation" class="smpl">DIGIT</a>               
    2151   <a href="#preferred.date.format" class="smpl">second</a>       = 2<a href="#notation" class="smpl">DIGIT</a>               
     2087  <a href="#preferred.date.format" class="smpl">hour</a>         = 2<a href="#abnf.dependencies" class="smpl">DIGIT</a>               
     2088  <a href="#preferred.date.format" class="smpl">minute</a>       = 2<a href="#abnf.dependencies" class="smpl">DIGIT</a>               
     2089  <a href="#preferred.date.format" class="smpl">second</a>       = 2<a href="#abnf.dependencies" class="smpl">DIGIT</a>               
    21522090</pre><p id="rfc.section.5.1.p.10">The semantics of <a href="#preferred.date.format" class="smpl">day-name</a>, <a href="#preferred.date.format" class="smpl">day</a>, <a href="#preferred.date.format" class="smpl">month</a>, <a href="#preferred.date.format" class="smpl">year</a>, and <a href="#preferred.date.format" class="smpl">time-of-day</a> are the same as those defined for the RFC 5322 constructs with the corresponding name (<a href="#RFC5322" id="rfc.xref.RFC5322.1"><cite title="Internet Message Format">[RFC5322]</cite></a>, <a href="http://tools.ietf.org/html/rfc5322#section-3.3">Section 3.3</a>).
    21532091      </p>
    … …  
    21552093         <p id="rfc.section.5.1.p.11">              Obsolete formats:</p>
    21562094      </div>
    2157       <div id="rfc.figure.u.12"></div><pre class="inline"><span id="rfc.iref.g.16"></span>  <a href="#obsolete.date.formats" class="smpl">obs-date</a>     = <a href="#obsolete.date.formats" class="smpl">rfc850-date</a> / <a href="#obsolete.date.formats" class="smpl">asctime-date</a>
    2158 </pre><div id="rfc.figure.u.13"></div><pre class="inline"><span id="rfc.iref.g.17"></span>  <a href="#obsolete.date.formats" class="smpl">rfc850-date</a>  = <a href="#obsolete.date.formats" class="smpl">day-name-l</a> "," <a href="#notation" class="smpl">SP</a> <a href="#obsolete.date.formats" class="smpl">date2</a> <a href="#notation" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#notation" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">GMT</a>
    2159   <a href="#obsolete.date.formats" class="smpl">date2</a>        = <a href="#preferred.date.format" class="smpl">day</a> "-" <a href="#preferred.date.format" class="smpl">month</a> "-" 2<a href="#notation" class="smpl">DIGIT</a>
     2095      <div id="rfc.figure.u.10"></div><pre class="inline"><span id="rfc.iref.g.16"></span>  <a href="#obsolete.date.formats" class="smpl">obs-date</a>     = <a href="#obsolete.date.formats" class="smpl">rfc850-date</a> / <a href="#obsolete.date.formats" class="smpl">asctime-date</a>
     2096</pre><div id="rfc.figure.u.11"></div><pre class="inline"><span id="rfc.iref.g.17"></span>  <a href="#obsolete.date.formats" class="smpl">rfc850-date</a>  = <a href="#obsolete.date.formats" class="smpl">day-name-l</a> "," <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#obsolete.date.formats" class="smpl">date2</a> <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">GMT</a>
     2097  <a href="#obsolete.date.formats" class="smpl">date2</a>        = <a href="#preferred.date.format" class="smpl">day</a> "-" <a href="#preferred.date.format" class="smpl">month</a> "-" 2<a href="#abnf.dependencies" class="smpl">DIGIT</a>
    21602098                 ; day-month-year (e.g., 02-Jun-82)
    21612099
    … …  
    21672105         / %x53.61.74.75.72.64.61.79 ; "Saturday", case-sensitive
    21682106         / %x53.75.6E.64.61.79 ; "Sunday", case-sensitive
    2169 </pre><div id="rfc.figure.u.14"></div><pre class="inline"><span id="rfc.iref.g.18"></span>  <a href="#obsolete.date.formats" class="smpl">asctime-date</a> = <a href="#preferred.date.format" class="smpl">day-name</a> <a href="#notation" class="smpl">SP</a> <a href="#obsolete.date.formats" class="smpl">date3</a> <a href="#notation" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#notation" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">year</a>
    2170   <a href="#obsolete.date.formats" class="smpl">date3</a>        = <a href="#preferred.date.format" class="smpl">month</a> <a href="#notation" class="smpl">SP</a> ( 2<a href="#notation" class="smpl">DIGIT</a> / ( <a href="#notation" class="smpl">SP</a> 1<a href="#notation" class="smpl">DIGIT</a> ))
     2107</pre><div id="rfc.figure.u.12"></div><pre class="inline"><span id="rfc.iref.g.18"></span>  <a href="#obsolete.date.formats" class="smpl">asctime-date</a> = <a href="#preferred.date.format" class="smpl">day-name</a> <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#obsolete.date.formats" class="smpl">date3</a> <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">time-of-day</a> <a href="#abnf.dependencies" class="smpl">SP</a> <a href="#preferred.date.format" class="smpl">year</a>
     2108  <a href="#obsolete.date.formats" class="smpl">date3</a>        = <a href="#preferred.date.format" class="smpl">month</a> <a href="#abnf.dependencies" class="smpl">SP</a> ( 2<a href="#abnf.dependencies" class="smpl">DIGIT</a> / ( <a href="#abnf.dependencies" class="smpl">SP</a> 1<a href="#abnf.dependencies" class="smpl">DIGIT</a> ))
    21712109                 ; month day (e.g., Jun  2)
    21722110</pre><div class="note" id="rfc.section.5.1.p.15">
    … …  
    21852123         By convention, the products are listed in order of their significance for identifying the application.
    21862124      </p>
    2187       <div id="rfc.figure.u.15"></div><pre class="inline"><span id="rfc.iref.g.19"></span><span id="rfc.iref.g.20"></span>  <a href="#product.tokens" class="smpl">product</a>         = <a href="#core.rules" class="smpl">token</a> ["/" <a href="#product.tokens" class="smpl">product-version</a>]
    2188   <a href="#product.tokens" class="smpl">product-version</a> = <a href="#core.rules" class="smpl">token</a>
     2125      <div id="rfc.figure.u.13"></div><pre class="inline"><span id="rfc.iref.g.19"></span><span id="rfc.iref.g.20"></span>  <a href="#product.tokens" class="smpl">product</a>         = <a href="#abnf.dependencies" class="smpl">token</a> ["/" <a href="#product.tokens" class="smpl">product-version</a>]
     2126  <a href="#product.tokens" class="smpl">product-version</a> = <a href="#abnf.dependencies" class="smpl">token</a>
    21892127</pre><p id="rfc.section.5.2.p.3">Examples:</p>
    2190       <div id="rfc.figure.u.16"></div><pre class="text">  User-Agent: CERN-LineMode/2.15 libwww/2.17b3
     2128      <div id="rfc.figure.u.14"></div><pre class="text">  User-Agent: CERN-LineMode/2.15 libwww/2.17b3
    21912129  Server: Apache/0.8.4
    21922130</pre><p id="rfc.section.5.2.p.5">Product tokens <em class="bcp14">SHOULD</em> be short and to the point. They <em class="bcp14">MUST NOT</em> be used for advertising or other non-essential information. Although any token octet <em class="bcp14">MAY</em> appear in a product-version, this token <em class="bcp14">SHOULD</em> only be used for a version identifier (i.e., successive versions of the same product <em class="bcp14">SHOULD</em> only differ in the product-version portion of the product value).
    … …  
    21992137         </p>
    22002138      </div>
    2201       <div id="rfc.figure.u.17"></div><pre class="inline"><span id="rfc.iref.g.21"></span>  <a href="#rule.charset" class="smpl">charset</a> = <a href="#core.rules" class="smpl">token</a>
     2139      <div id="rfc.figure.u.15"></div><pre class="inline"><span id="rfc.iref.g.21"></span>  <a href="#rule.charset" class="smpl">charset</a> = <a href="#abnf.dependencies" class="smpl">token</a>
    22022140</pre><p id="rfc.section.5.3.p.4">Although HTTP allows an arbitrary token to be used as a charset value, any token that has a predefined value within the IANA
    22032141         Character Set registry <em class="bcp14">MUST</em> represent the character encoding defined by that registry. Applications <em class="bcp14">SHOULD</em> limit their use of character encodings to those defined within the IANA registry.
    … …  
    22132151         directly, and only decoded by the recipient.
    22142152      </p>
    2215       <div id="rfc.figure.u.18"></div><pre class="inline"><span id="rfc.iref.g.22"></span>  <a href="#content.codings" class="smpl">content-coding</a>   = <a href="#core.rules" class="smpl">token</a>
     2153      <div id="rfc.figure.u.16"></div><pre class="inline"><span id="rfc.iref.g.22"></span>  <a href="#content.codings" class="smpl">content-coding</a>   = <a href="#abnf.dependencies" class="smpl">token</a>
    22162154</pre><p id="rfc.section.5.4.p.3">All content-coding values are case-insensitive. HTTP/1.1 uses content-coding values in the <a href="#header.accept-encoding" class="smpl">Accept-Encoding</a> (<a href="#header.accept-encoding" id="rfc.xref.header.accept-encoding.2" title="Accept-Encoding">Section&nbsp;9.3</a>) and <a href="#header.content-encoding" class="smpl">Content-Encoding</a> (<a href="#header.content-encoding" id="rfc.xref.header.content-encoding.1" title="Content-Encoding">Section&nbsp;9.6</a>) header fields. Although the value describes the content-coding, what is more important is that it indicates what decoding
    22172155         mechanism will be required to remove the encoding.
    … …  
    22202158      </p>
    22212159      <ul class="empty">
    2222          <li>See <a href="p1-messaging.html#compress.coding" title="Compress Coding">Section 4.2.1</a> of <a href="#Part1" id="rfc.xref.Part1.37"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
     2160         <li>See <a href="p1-messaging.html#compress.coding" title="Compress Coding">Section 4.2.1</a> of <a href="#Part1" id="rfc.xref.Part1.23"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
    22232161         </li>
    22242162      </ul>
    … …  
    22262164      </p>
    22272165      <ul class="empty">
    2228          <li>See <a href="p1-messaging.html#deflate.coding" title="Deflate Coding">Section 4.2.2</a> of <a href="#Part1" id="rfc.xref.Part1.38"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
     2166         <li>See <a href="p1-messaging.html#deflate.coding" title="Deflate Coding">Section 4.2.2</a> of <a href="#Part1" id="rfc.xref.Part1.24"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
    22292167         </li>
    22302168      </ul>
    … …  
    22322170      </p>
    22332171      <ul class="empty">
    2234          <li>See <a href="p1-messaging.html#gzip.coding" title="Gzip Coding">Section 4.2.3</a> of <a href="#Part1" id="rfc.xref.Part1.39"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
     2172         <li>See <a href="p1-messaging.html#gzip.coding" title="Gzip Coding">Section 4.2.3</a> of <a href="#Part1" id="rfc.xref.Part1.25"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
    22352173         </li>
    22362174      </ul>
    … …  
    22442182         <li>Pointer to specification text</li>
    22452183      </ul>
    2246       <p id="rfc.section.5.4.1.p.3">Names of content codings <em class="bcp14">MUST NOT</em> overlap with names of transfer codings (<a href="p1-messaging.html#transfer.codings" title="Transfer Codings">Section 4</a> of <a href="#Part1" id="rfc.xref.Part1.40"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>), unless the encoding transformation is identical (as is the case for the compression codings defined in <a href="p1-messaging.html#compression.codings" title="Compression Codings">Section 4.2</a> of <a href="#Part1" id="rfc.xref.Part1.41"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
     2184      <p id="rfc.section.5.4.1.p.3">Names of content codings <em class="bcp14">MUST NOT</em> overlap with names of transfer codings (<a href="p1-messaging.html#transfer.codings" title="Transfer Codings">Section 4</a> of <a href="#Part1" id="rfc.xref.Part1.26"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>), unless the encoding transformation is identical (as is the case for the compression codings defined in <a href="p1-messaging.html#compression.codings" title="Compression Codings">Section 4.2</a> of <a href="#Part1" id="rfc.xref.Part1.27"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
    22472185      </p>
    22482186      <p id="rfc.section.5.4.1.p.4">Values to be added to this name space require IETF Review (see <a href="http://tools.ietf.org/html/rfc5226#section-4.1">Section 4.1</a> of <a href="#RFC5226" id="rfc.xref.RFC5226.3"><cite title="Guidelines for Writing an IANA Considerations Section in RFCs">[RFC5226]</cite></a>), and <em class="bcp14">MUST</em> conform to the purpose of content coding defined in this section.
    … …  
    22532191      <p id="rfc.section.5.5.p.1">HTTP uses Internet Media Types <a href="#RFC2046" id="rfc.xref.RFC2046.1"><cite title="Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types">[RFC2046]</cite></a> in the <a href="#header.content-type" class="smpl">Content-Type</a> (<a href="#header.content-type" id="rfc.xref.header.content-type.3" title="Content-Type">Section&nbsp;9.9</a>) and <a href="#header.accept" class="smpl">Accept</a> (<a href="#header.accept" id="rfc.xref.header.accept.2" title="Accept">Section&nbsp;9.1</a>) header fields in order to provide open and extensible data typing and type negotiation.
    22542192      </p>
    2255       <div id="rfc.figure.u.19"></div><pre class="inline"><span id="rfc.iref.g.24"></span><span id="rfc.iref.g.25"></span><span id="rfc.iref.g.26"></span>  <a href="#media.types" class="smpl">media-type</a> = <a href="#media.types" class="smpl">type</a> "/" <a href="#media.types" class="smpl">subtype</a> *( <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> <a href="#rule.parameter" class="smpl">parameter</a> )
    2256   <a href="#media.types" class="smpl">type</a>       = <a href="#core.rules" class="smpl">token</a>
    2257   <a href="#media.types" class="smpl">subtype</a>    = <a href="#core.rules" class="smpl">token</a>
     2193      <div id="rfc.figure.u.17"></div><pre class="inline"><span id="rfc.iref.g.24"></span><span id="rfc.iref.g.25"></span><span id="rfc.iref.g.26"></span>  <a href="#media.types" class="smpl">media-type</a> = <a href="#media.types" class="smpl">type</a> "/" <a href="#media.types" class="smpl">subtype</a> *( <a href="#abnf.dependencies" class="smpl">OWS</a> ";" <a href="#abnf.dependencies" class="smpl">OWS</a> <a href="#rule.parameter" class="smpl">parameter</a> )
     2194  <a href="#media.types" class="smpl">type</a>       = <a href="#abnf.dependencies" class="smpl">token</a>
     2195  <a href="#media.types" class="smpl">subtype</a>    = <a href="#abnf.dependencies" class="smpl">token</a>
    22582196</pre><div id="rule.parameter">
    22592197         <p id="rfc.section.5.5.p.3">      The type/subtype <em class="bcp14">MAY</em> be followed by parameters in the form of attribute/value pairs.
    22602198         </p>
    22612199      </div>
    2262       <div id="rfc.figure.u.20"></div><pre class="inline"><span id="rfc.iref.g.27"></span><span id="rfc.iref.g.28"></span><span id="rfc.iref.g.29"></span>  <a href="#rule.parameter" class="smpl">parameter</a>      = <a href="#rule.parameter" class="smpl">attribute</a> "=" <a href="#rule.parameter" class="smpl">value</a>
    2263   <a href="#rule.parameter" class="smpl">attribute</a>      = <a href="#core.rules" class="smpl">token</a>
    2264   <a href="#rule.parameter" class="smpl">value</a>          = <a href="#core.rules" class="smpl">word</a>
     2200      <div id="rfc.figure.u.18"></div><pre class="inline"><span id="rfc.iref.g.27"></span><span id="rfc.iref.g.28"></span><span id="rfc.iref.g.29"></span>  <a href="#rule.parameter" class="smpl">parameter</a>      = <a href="#rule.parameter" class="smpl">attribute</a> "=" <a href="#rule.parameter" class="smpl">value</a>
     2201  <a href="#rule.parameter" class="smpl">attribute</a>      = <a href="#abnf.dependencies" class="smpl">token</a>
     2202  <a href="#rule.parameter" class="smpl">value</a>          = <a href="#abnf.dependencies" class="smpl">word</a>
    22652203</pre><p id="rfc.section.5.5.p.5">The type, subtype, and parameter attribute names are case-insensitive. Parameter values might or might not be case-sensitive,
    22662204         depending on the semantics of the parameter name. The presence or absence of a parameter might be significant to the processing
    22672205         of a media-type, depending on its definition within the media type registry.
    22682206      </p>
    2269       <p id="rfc.section.5.5.p.6">A parameter value that matches the <a href="#core.rules" class="smpl">token</a> production can be transmitted as either a token or within a quoted-string. The quoted and unquoted values are equivalent.
     2207      <p id="rfc.section.5.5.p.6">A parameter value that matches the <a href="#abnf.dependencies" class="smpl">token</a> production can be transmitted as either a token or within a quoted-string. The quoted and unquoted values are equivalent.
    22702208      </p>
    22712209      <p id="rfc.section.5.5.p.7">Note that some older HTTP applications do not recognize media type parameters. When sending data to older HTTP applications,
    … …  
    23102248         of subtags:
    23112249      </p>
    2312       <div id="rfc.figure.u.21"></div><pre class="inline"><span id="rfc.iref.g.30"></span>  <a href="#language.tags" class="smpl">language-tag</a> = &lt;Language-Tag, defined in <a href="#RFC5646" id="rfc.xref.RFC5646.2"><cite title="Tags for Identifying Languages">[RFC5646]</cite></a>, <a href="http://tools.ietf.org/html/rfc5646#section-2.1">Section 2.1</a>&gt;
     2250      <div id="rfc.figure.u.19"></div><pre class="inline"><span id="rfc.iref.g.30"></span>  <a href="#language.tags" class="smpl">language-tag</a> = &lt;Language-Tag, defined in <a href="#RFC5646" id="rfc.xref.RFC5646.2"><cite title="Tags for Identifying Languages">[RFC5646]</cite></a>, <a href="http://tools.ietf.org/html/rfc5646#section-2.1">Section 2.1</a>&gt;
    23132251</pre><p id="rfc.section.5.6.p.4">White space is not allowed within the tag and all tags are case-insensitive. The name space of language subtags is administered
    23142252         by the IANA (see &lt;<a href="http://www.iana.org/assignments/language-subtag-registry">http://www.iana.org/assignments/language-subtag-registry</a>&gt;).
    23152253      </p>
    2316       <div id="rfc.figure.u.22"></div>
     2254      <div id="rfc.figure.u.20"></div>
    23172255      <p>Example tags include:</p>  <pre class="text">  en, en-US, es-419, az-Arab, x-pig-latin, man-Nkoo-GN
    23182256</pre> <p id="rfc.section.5.6.p.6">See <a href="#RFC5646" id="rfc.xref.RFC5646.3"><cite title="Tags for Identifying Languages">[RFC5646]</cite></a> for further information.
    … …  
    23432281               <tr>
    23442282                  <td class="left">Content-Length</td>
    2345                   <td class="left"><a href="p1-messaging.html#header.content-length" title="Content-Length">Section 3.3.2</a> of <a href="#Part1" id="rfc.xref.Part1.42"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a></td>
     2283                  <td class="left"><a href="p1-messaging.html#header.content-length" title="Content-Length">Section 3.3.2</a> of <a href="#Part1" id="rfc.xref.Part1.28"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a></td>
    23462284               </tr>
    23472285               <tr>
    … …  
    23532291      </div>
    23542292      <h2 id="rfc.section.6.2"><a href="#rfc.section.6.2">6.2</a>&nbsp;<a id="payload.body" href="#payload.body">Payload Body</a></h2>
    2355       <p id="rfc.section.6.2.p.1">A payload body is only present in a message when a message body is present, as described in <a href="p1-messaging.html#message.body" title="Message Body">Section 3.3</a> of <a href="#Part1" id="rfc.xref.Part1.43"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. The payload body is obtained from the message body by decoding any <a href="p1-messaging.html#header.transfer-encoding" class="smpl">Transfer-Encoding</a> that might have been applied to ensure safe and proper transfer of the message.
     2293      <p id="rfc.section.6.2.p.1">A payload body is only present in a message when a message body is present, as described in <a href="p1-messaging.html#message.body" title="Message Body">Section 3.3</a> of <a href="#Part1" id="rfc.xref.Part1.29"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. The payload body is obtained from the message body by decoding any <a href="p1-messaging.html#header.transfer-encoding" class="smpl">Transfer-Encoding</a> that might have been applied to ensure safe and proper transfer of the message.
    23562294      </p>
    23572295      <div id="rfc.iref.r.1"></div>
    … …  
    23722310         in an HTTP message, it is referred to as the payload of the message.
    23732311      </p>
    2374       <p id="rfc.section.7.p.4">A representation body is only present in a message when a message body is present, as described in <a href="p1-messaging.html#message.body" title="Message Body">Section 3.3</a> of <a href="#Part1" id="rfc.xref.Part1.44"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. The representation body is obtained from the message body by decoding any <a href="p1-messaging.html#header.transfer-encoding" class="smpl">Transfer-Encoding</a> that might have been applied to ensure safe and proper transfer of the message.
     2312      <p id="rfc.section.7.p.4">A representation body is only present in a message when a message body is present, as described in <a href="p1-messaging.html#message.body" title="Message Body">Section 3.3</a> of <a href="#Part1" id="rfc.xref.Part1.30"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. The representation body is obtained from the message body by decoding any <a href="p1-messaging.html#header.transfer-encoding" class="smpl">Transfer-Encoding</a> that might have been applied to ensure safe and proper transfer of the message.
    23752313      </p>
    23762314      <h2 id="rfc.section.7.1"><a href="#rfc.section.7.1">7.1</a>&nbsp;<a id="identifying.response.associated.with.representation" href="#identifying.response.associated.with.representation">Identifying the Resource Associated with a Representation</a></h2>
    23772315      <p id="rfc.section.7.1.p.1">It is sometimes necessary to determine an identifier for the resource associated with a representation.</p>
    23782316      <p id="rfc.section.7.1.p.2">An HTTP request representation, when present, is always associated with an anonymous (i.e., unidentified) resource.</p>
    2379       <p id="rfc.section.7.1.p.3">In the common case, an HTTP response is a representation of the target resource (see <a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.45"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). However, this is not always the case. To determine the URI of the resource a response is associated with, the following
     2317      <p id="rfc.section.7.1.p.3">In the common case, an HTTP response is a representation of the target resource (see <a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.31"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). However, this is not always the case. To determine the URI of the resource a response is associated with, the following
    23802318         rules are used (with the first applicable one being selected):
    23812319      </p>
    … …  
    24352373         </table>
    24362374      </div>
    2437       <p id="rfc.section.7.2.p.3">Additional header fields define metadata about the selected representation, which might differ from the representation included
     2375      <p id="rfc.section.7.2.p.3"><span id="rfc.iref.s.43"></span> We use the term "<dfn>selected representation</dfn>" to refer to the the current representation of a target resource that would have been selected in a successful response if
     2376         the same request had used the method GET and excluded any conditional request header fields.
     2377      </p>
     2378      <p id="rfc.section.7.2.p.4">Additional header fields define metadata about the selected representation, which might differ from the representation included
    24382379         in the message for responses to some state-changing methods. The following header fields are defined as selected representation
    24392380         metadata:
    … …  
    24662407      <p id="rfc.section.7.3.p.2">The data type of the representation data is determined via the header fields <a href="#header.content-type" class="smpl">Content-Type</a> and <a href="#header.content-encoding" class="smpl">Content-Encoding</a>. These define a two-layer, ordered encoding model:
    24672408      </p>
    2468       <div id="rfc.figure.u.23"></div><pre class="text">  representation-data := Content-Encoding( Content-Type( bits ) )
     2409      <div id="rfc.figure.u.21"></div><pre class="text">  representation-data := Content-Encoding( Content-Type( bits ) )
    24692410</pre><p id="rfc.section.7.3.p.4"> <a href="#header.content-type" class="smpl">Content-Type</a> specifies the media type of the underlying data, which defines both the data format and how that data <em class="bcp14">SHOULD</em> be processed by the recipient (within the scope of the request method semantics). Any HTTP/1.1 message containing a payload
    24702411         body <em class="bcp14">SHOULD</em> include a Content-Type header field defining the media type of the associated representation unless that metadata is unknown
    … …  
    25352476            (Not Acceptable)</a> response.
    25362477      </p>
    2537       <p id="rfc.section.8.1.p.5">Many of the mechanisms for expressing preferences use quality values to declare relative preference. See <a href="p1-messaging.html#quality.values" title="Quality Values">Section 4.3.1</a> of <a href="#Part1" id="rfc.xref.Part1.46"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for more information.
     2478      <p id="rfc.section.8.1.p.5">Many of the mechanisms for expressing preferences use quality values to declare relative preference. See <a href="p1-messaging.html#quality.values" title="Quality Values">Section 4.3.1</a> of <a href="#Part1" id="rfc.xref.Part1.32"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for more information.
    25382479      </p>
    25392480      <p id="rfc.section.8.1.p.6">HTTP/1.1 includes the following header fields for enabling server-driven negotiation through description of user agent capabilities
    … …  
    25772518         for an in-line image.
    25782519      </p>
    2579       <div id="rfc.figure.u.24"></div><pre class="inline"><span id="rfc.iref.g.31"></span><span id="rfc.iref.g.32"></span><span id="rfc.iref.g.33"></span><span id="rfc.iref.g.34"></span>  <a href="#header.accept" class="smpl">Accept</a> = #( <a href="#header.accept" class="smpl">media-range</a> [ <a href="#header.accept" class="smpl">accept-params</a> ] )
     2520      <div id="rfc.figure.u.22"></div><pre class="inline"><span id="rfc.iref.g.31"></span><span id="rfc.iref.g.32"></span><span id="rfc.iref.g.33"></span><span id="rfc.iref.g.34"></span>  <a href="#header.accept" class="smpl">Accept</a> = #( <a href="#header.accept" class="smpl">media-range</a> [ <a href="#header.accept" class="smpl">accept-params</a> ] )
    25802521 
    25812522  <a href="#header.accept" class="smpl">media-range</a>    = ( "*/*"
    25822523                   / ( <a href="#media.types" class="smpl">type</a> "/" "*" )
    25832524                   / ( <a href="#media.types" class="smpl">type</a> "/" <a href="#media.types" class="smpl">subtype</a> )
    2584                    ) *( <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> <a href="#rule.parameter" class="smpl">parameter</a> )
    2585   <a href="#header.accept" class="smpl">accept-params</a>  = <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> *( <a href="#header.accept" class="smpl">accept-ext</a> )
    2586   <a href="#header.accept" class="smpl">accept-ext</a>     = <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> <a href="#core.rules" class="smpl">token</a> [ "=" <a href="#core.rules" class="smpl">word</a> ]
     2525                   ) *( <a href="#abnf.dependencies" class="smpl">OWS</a> ";" <a href="#abnf.dependencies" class="smpl">OWS</a> <a href="#rule.parameter" class="smpl">parameter</a> )
     2526  <a href="#header.accept" class="smpl">accept-params</a>  = <a href="#abnf.dependencies" class="smpl">OWS</a> ";" <a href="#abnf.dependencies" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> *( <a href="#header.accept" class="smpl">accept-ext</a> )
     2527  <a href="#header.accept" class="smpl">accept-ext</a>     = <a href="#abnf.dependencies" class="smpl">OWS</a> ";" <a href="#abnf.dependencies" class="smpl">OWS</a> <a href="#abnf.dependencies" class="smpl">token</a> [ "=" <a href="#abnf.dependencies" class="smpl">word</a> ]
    25872528</pre><p id="rfc.section.9.1.p.3">The asterisk "*" character is used to group media types into ranges, with "*/*" indicating all media types and "type/*" indicating
    25882529         all subtypes of that type. The media-range <em class="bcp14">MAY</em> include media type parameters that are applicable to that range.
    … …  
    25902531      <p id="rfc.section.9.1.p.4">Each media-range <em class="bcp14">MAY</em> be followed by one or more accept-params, beginning with the "q" parameter for indicating a relative quality factor. The first
    25912532         "q" parameter (if any) separates the media-range parameter(s) from the accept-params. Quality factors allow the user or user
    2592          agent to indicate the relative degree of preference for that media-range, using the qvalue scale from 0 to 1 (<a href="p1-messaging.html#quality.values" title="Quality Values">Section 4.3.1</a> of <a href="#Part1" id="rfc.xref.Part1.47"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). The default value is q=1.
     2533         agent to indicate the relative degree of preference for that media-range, using the qvalue scale from 0 to 1 (<a href="p1-messaging.html#quality.values" title="Quality Values">Section 4.3.1</a> of <a href="#Part1" id="rfc.xref.Part1.33"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). The default value is q=1.
    25932534      </p>
    25942535      <div class="note" id="rfc.section.9.1.p.5">
    … …  
    26002541      </div>
    26012542      <p id="rfc.section.9.1.p.6">The example</p>
    2602       <div id="rfc.figure.u.25"></div><pre class="text">  Accept: audio/*; q=0.2, audio/basic
     2543      <div id="rfc.figure.u.23"></div><pre class="text">  Accept: audio/*; q=0.2, audio/basic
    26032544</pre><p id="rfc.section.9.1.p.8"> <em class="bcp14">SHOULD</em> be interpreted as "I prefer audio/basic, but send me any audio type if it is the best available after an 80% mark-down in
    26042545         quality".
    … …  
    26092550      </p>
    26102551      <p id="rfc.section.9.1.p.10">A more elaborate example is</p>
    2611       <div id="rfc.figure.u.26"></div><pre class="text">  Accept: text/plain; q=0.5, text/html,
     2552      <div id="rfc.figure.u.24"></div><pre class="text">  Accept: text/plain; q=0.5, text/html,
    26122553          text/x-dvi; q=0.8, text/x-c
    26132554</pre><p id="rfc.section.9.1.p.12">Verbally, this would be interpreted as "text/html and text/x-c are the preferred media types, but if they do not exist, then
    … …  
    26172558         to a given type, the most specific reference has precedence. For example,
    26182559      </p>
    2619       <div id="rfc.figure.u.27"></div><pre class="text">  Accept: text/*, text/plain, text/plain;format=flowed, */*
     2560      <div id="rfc.figure.u.25"></div><pre class="text">  Accept: text/*, text/plain, text/plain;format=flowed, */*
    26202561</pre><p id="rfc.section.9.1.p.15">have the following precedence: </p>
    26212562      <ol>
    … …  
    26282569         which matches that type. For example,
    26292570      </p>
    2630       <div id="rfc.figure.u.28"></div><pre class="text">  Accept: text/*;q=0.3, text/html;q=0.7, text/html;level=1,
     2571      <div id="rfc.figure.u.26"></div><pre class="text">  Accept: text/*;q=0.3, text/html;q=0.7, text/html;level=1,
    26312572          text/html;level=2;q=0.4, */*;q=0.5
    26322573</pre><p id="rfc.section.9.1.p.18">would cause the following values to be associated:</p>
    … …  
    26772618         that capability to a server which is capable of representing documents in those character encodings.
    26782619      </p>
    2679       <div id="rfc.figure.u.29"></div><pre class="inline"><span id="rfc.iref.g.35"></span>  <a href="#header.accept-charset" class="smpl">Accept-Charset</a> = 1#( ( <a href="#rule.charset" class="smpl">charset</a> / "*" )
    2680                          [ <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> ] )
     2620      <div id="rfc.figure.u.27"></div><pre class="inline"><span id="rfc.iref.g.35"></span>  <a href="#header.accept-charset" class="smpl">Accept-Charset</a> = 1#( ( <a href="#rule.charset" class="smpl">charset</a> / "*" )
     2621                         [ <a href="#abnf.dependencies" class="smpl">OWS</a> ";" <a href="#abnf.dependencies" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> ] )
    26812622</pre><p id="rfc.section.9.2.p.3">Character encoding values (a.k.a., charsets) are described in <a href="#character.sets" title="Character Encodings (charset)">Section&nbsp;5.3</a>. Each charset <em class="bcp14">MAY</em> be given an associated quality value which represents the user's preference for that charset. The default value is q=1. An
    26822623         example is
    26832624      </p>
    2684       <div id="rfc.figure.u.30"></div><pre class="text">  Accept-Charset: iso-8859-5, unicode-1-1;q=0.8
     2625      <div id="rfc.figure.u.28"></div><pre class="text">  Accept-Charset: iso-8859-5, unicode-1-1;q=0.8
    26852626</pre><p id="rfc.section.9.2.p.5">The special value "*", if present in the Accept-Charset field, matches every character encoding which is not mentioned elsewhere
    26862627         in the Accept-Charset field. If no "*" is present in an Accept-Charset field, then all character encodings not explicitly
    … …  
    26972638         no encoding is preferred.
    26982639      </p>
    2699       <div id="rfc.figure.u.31"></div><pre class="inline"><span id="rfc.iref.g.36"></span><span id="rfc.iref.g.37"></span>  <a href="#header.accept-encoding" class="smpl">Accept-Encoding</a>  = #( <a href="#header.accept-encoding" class="smpl">codings</a> [ <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> ] )
     2640      <div id="rfc.figure.u.29"></div><pre class="inline"><span id="rfc.iref.g.36"></span><span id="rfc.iref.g.37"></span>  <a href="#header.accept-encoding" class="smpl">Accept-Encoding</a>  = #( <a href="#header.accept-encoding" class="smpl">codings</a> [ <a href="#abnf.dependencies" class="smpl">OWS</a> ";" <a href="#abnf.dependencies" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> ] )
    27002641  <a href="#header.accept-encoding" class="smpl">codings</a>          = <a href="#content.codings" class="smpl">content-coding</a> / "identity" / "*"
    27012642</pre><p id="rfc.section.9.3.p.3">Each codings value <em class="bcp14">MAY</em> be given an associated quality value which represents the preference for that encoding. The default value is q=1.
    27022643      </p>
    27032644      <p id="rfc.section.9.3.p.4">For example,</p>
    2704       <div id="rfc.figure.u.32"></div><pre class="text">  Accept-Encoding: compress, gzip
     2645      <div id="rfc.figure.u.30"></div><pre class="text">  Accept-Encoding: compress, gzip
    27052646  Accept-Encoding:
    27062647  Accept-Encoding: *
    … …  
    27182659         </li>
    27192660         <li>If the representation's content-coding is one of the content-codings listed in the Accept-Encoding field, then it is acceptable
    2720             unless it is accompanied by a qvalue of 0. (As defined in <a href="p1-messaging.html#quality.values" title="Quality Values">Section 4.3.1</a> of <a href="#Part1" id="rfc.xref.Part1.48"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, a qvalue of 0 means "not acceptable".)
     2661            unless it is accompanied by a qvalue of 0. (As defined in <a href="p1-messaging.html#quality.values" title="Quality Values">Section 4.3.1</a> of <a href="#Part1" id="rfc.xref.Part1.34"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, a qvalue of 0 means "not acceptable".)
    27212662         </li>
    27222663         <li>If multiple content-codings are acceptable, then the acceptable content-coding with the highest non-zero qvalue is preferred.</li>
    … …  
    27402681         in the response. Language tags are defined in <a href="#language.tags" title="Language Tags">Section&nbsp;5.6</a>.
    27412682      </p>
    2742       <div id="rfc.figure.u.33"></div><pre class="inline"><span id="rfc.iref.g.38"></span><span id="rfc.iref.g.39"></span>  <a href="#header.accept-language" class="smpl">Accept-Language</a> =
    2743                     1#( <a href="#header.accept-language" class="smpl">language-range</a> [ <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> ] )
     2683      <div id="rfc.figure.u.31"></div><pre class="inline"><span id="rfc.iref.g.38"></span><span id="rfc.iref.g.39"></span>  <a href="#header.accept-language" class="smpl">Accept-Language</a> =
     2684                    1#( <a href="#header.accept-language" class="smpl">language-range</a> [ <a href="#abnf.dependencies" class="smpl">OWS</a> ";" <a href="#abnf.dependencies" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> ] )
    27442685  <a href="#header.accept-language" class="smpl">language-range</a>  =
    27452686            &lt;language-range, defined in <a href="#RFC4647" id="rfc.xref.RFC4647.1"><cite title="Matching of Language Tags">[RFC4647]</cite></a>, <a href="http://tools.ietf.org/html/rfc4647#section-2.1">Section 2.1</a>&gt;
    … …  
    27472688         languages specified by that range. The quality value defaults to "q=1". For example,
    27482689      </p>
    2749       <div id="rfc.figure.u.34"></div><pre class="text">  Accept-Language: da, en-gb;q=0.8, en;q=0.7
     2690      <div id="rfc.figure.u.32"></div><pre class="text">  Accept-Language: da, en-gb;q=0.8, en;q=0.7
    27502691</pre><p id="rfc.section.9.4.p.5">would mean: "I prefer Danish, but will accept British English and other types of English". (see also <a href="http://tools.ietf.org/html/rfc4647#section-2.3">Section 2.3</a> of <a href="#RFC4647" id="rfc.xref.RFC4647.2"><cite title="Matching of Language Tags">[RFC4647]</cite></a>)
    27512692      </p>
    … …  
    27572698      </div>
    27582699      <p id="rfc.section.9.4.p.8">It might be contrary to the privacy expectations of the user to send an Accept-Language header field with the complete linguistic
    2759          preferences of the user in every request. For a discussion of this issue, see <a href="#privacy.issues.connected.to.accept.header.fields" title="Privacy Issues Connected to Accept Header Fields">Section&nbsp;11.5</a>.
     2700         preferences of the user in every request. For a discussion of this issue, see <a href="#privacy.issues.connected.to.accept.header.fields" title="Privacy Issues Connected to Accept Header Fields">Section&nbsp;12.5</a>.
    27602701      </p>
    27612702      <p id="rfc.section.9.4.p.9">As intelligibility is highly dependent on the individual user, it is recommended that client applications make the choice
    … …  
    27752716         is strictly to inform the recipient of valid request methods associated with the resource.
    27762717      </p>
    2777       <div id="rfc.figure.u.35"></div><pre class="inline"><span id="rfc.iref.g.40"></span>  <a href="#header.allow" class="smpl">Allow</a> = #<a href="#methods" class="smpl">method</a>
     2718      <div id="rfc.figure.u.33"></div><pre class="inline"><span id="rfc.iref.g.40"></span>  <a href="#header.allow" class="smpl">Allow</a> = #<a href="#methods" class="smpl">method</a>
    27782719</pre><p id="rfc.section.9.5.p.3">Example of use:</p>
    2779       <div id="rfc.figure.u.36"></div><pre class="text">  Allow: GET, HEAD, PUT
     2720      <div id="rfc.figure.u.34"></div><pre class="text">  Allow: GET, HEAD, PUT
    27802721</pre><p id="rfc.section.9.5.p.5">The actual set of allowed methods is defined by the origin server at the time of each request.</p>
    27812722      <p id="rfc.section.9.5.p.6">A proxy <em class="bcp14">MUST NOT</em> modify the Allow header field — it does not need to understand all the methods specified in order to handle them according
    … …  
    27892730         its underlying media type.
    27902731      </p>
    2791       <div id="rfc.figure.u.37"></div><pre class="inline"><span id="rfc.iref.g.41"></span>  <a href="#header.content-encoding" class="smpl">Content-Encoding</a> = 1#<a href="#content.codings" class="smpl">content-coding</a>
     2732      <div id="rfc.figure.u.35"></div><pre class="inline"><span id="rfc.iref.g.41"></span>  <a href="#header.content-encoding" class="smpl">Content-Encoding</a> = 1#<a href="#content.codings" class="smpl">content-coding</a>
    27922733</pre><p id="rfc.section.9.6.p.3">Content codings are defined in <a href="#content.codings" title="Content Codings">Section&nbsp;5.4</a>. An example of its use is
    27932734      </p>
    2794       <div id="rfc.figure.u.38"></div><pre class="text">  Content-Encoding: gzip
     2735      <div id="rfc.figure.u.36"></div><pre class="text">  Content-Encoding: gzip
    27952736</pre><p id="rfc.section.9.6.p.5">The content-coding is a characteristic of the representation. Typically, the representation body is stored with this encoding
    27962737         and is only decoded before rendering or analogous usage. However, a transforming proxy <em class="bcp14">MAY</em> modify the content-coding if the new coding is known to be acceptable to the recipient, unless the "no-transform" cache-control
    … …  
    28162757         that this might not be equivalent to all the languages used within the representation.
    28172758      </p>
    2818       <div id="rfc.figure.u.39"></div><pre class="inline"><span id="rfc.iref.g.42"></span>  <a href="#header.content-language" class="smpl">Content-Language</a> = 1#<a href="#language.tags" class="smpl">language-tag</a>
     2759      <div id="rfc.figure.u.37"></div><pre class="inline"><span id="rfc.iref.g.42"></span>  <a href="#header.content-language" class="smpl">Content-Language</a> = 1#<a href="#language.tags" class="smpl">language-tag</a>
    28192760</pre><p id="rfc.section.9.7.p.3">Language tags are defined in <a href="#language.tags" title="Language Tags">Section&nbsp;5.6</a>. The primary purpose of Content-Language is to allow a user to identify and differentiate representations according to the
    28202761         user's own preferred language. Thus, if the body content is intended only for a Danish-literate audience, the appropriate
    28212762         field is
    28222763      </p>
    2823       <div id="rfc.figure.u.40"></div><pre class="text">  Content-Language: da
     2764      <div id="rfc.figure.u.38"></div><pre class="text">  Content-Language: da
    28242765</pre><p id="rfc.section.9.7.p.5">If no Content-Language is specified, the default is that the content is intended for all language audiences. This might mean
    28252766         that the sender does not consider it to be specific to any natural language, or that the sender does not know for which language
    … …  
    28292770         simultaneously in the original Maori and English versions, would call for
    28302771      </p>
    2831       <div id="rfc.figure.u.41"></div><pre class="text">  Content-Language: mi, en
     2772      <div id="rfc.figure.u.39"></div><pre class="text">  Content-Language: mi, en
    28322773</pre><p id="rfc.section.9.7.p.8">However, just because multiple languages are present within a representation does not mean that it is intended for multiple
    28332774         linguistic audiences. An example would be a beginner's language primer, such as "A First Lesson in Latin", which is clearly
    … …  
    28422783         message. In other words, if one were to perform a GET on this URI at the time of this message's generation, then a <a href="#status.200" class="smpl">200 (OK)</a> response would contain the same representation that is enclosed as payload in this message.
    28432784      </p>
    2844       <div id="rfc.figure.u.42"></div><pre class="inline"><span id="rfc.iref.g.43"></span>  <a href="#header.content-location" class="smpl">Content-Location</a> = <a href="#abnf.dependencies" class="smpl">absolute-URI</a> / <a href="#abnf.dependencies" class="smpl">partial-URI</a>
    2845 </pre><p id="rfc.section.9.8.p.3">The Content-Location value is not a replacement for the effective Request URI (<a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.49"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). It is representation metadata. It has the same syntax and semantics as the header field of the same name defined for MIME
     2785      <div id="rfc.figure.u.40"></div><pre class="inline"><span id="rfc.iref.g.43"></span>  <a href="#header.content-location" class="smpl">Content-Location</a> = <a href="#abnf.dependencies" class="smpl">absolute-URI</a> / <a href="#abnf.dependencies" class="smpl">partial-URI</a>
     2786</pre><p id="rfc.section.9.8.p.3">The Content-Location value is not a replacement for the effective Request URI (<a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.35"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). It is representation metadata. It has the same syntax and semantics as the header field of the same name defined for MIME
    28462787         body parts in <a href="http://tools.ietf.org/html/rfc2557#section-4">Section 4</a> of <a href="#RFC2557" id="rfc.xref.RFC2557.1"><cite title="MIME Encapsulation of Aggregate Documents, such as HTML (MHTML)">[RFC2557]</cite></a>. However, its appearance in an HTTP message has some special implications for HTTP recipients.
    28472788      </p>
    … …  
    28822823         the media type is that which would have been sent had the request been a GET.
    28832824      </p>
    2884       <div id="rfc.figure.u.43"></div><pre class="inline"><span id="rfc.iref.g.44"></span>  <a href="#header.content-type" class="smpl">Content-Type</a> = <a href="#media.types" class="smpl">media-type</a>
     2825      <div id="rfc.figure.u.41"></div><pre class="inline"><span id="rfc.iref.g.44"></span>  <a href="#header.content-type" class="smpl">Content-Type</a> = <a href="#media.types" class="smpl">media-type</a>
    28852826</pre><p id="rfc.section.9.9.p.3">Media types are defined in <a href="#media.types" title="Media Types">Section&nbsp;5.5</a>. An example of the field is
    28862827      </p>
    2887       <div id="rfc.figure.u.44"></div><pre class="text">  Content-Type: text/html; charset=ISO-8859-4
     2828      <div id="rfc.figure.u.42"></div><pre class="text">  Content-Type: text/html; charset=ISO-8859-4
    28882829</pre><p id="rfc.section.9.9.p.5">Further discussion of Content-Type is provided in <a href="#representation.data" title="Representation Data">Section&nbsp;7.3</a>.
    28892830      </p>
    … …  
    28942835         Origination Date Field (orig-date) defined in <a href="http://tools.ietf.org/html/rfc5322#section-3.6.1">Section 3.6.1</a> of <a href="#RFC5322" id="rfc.xref.RFC5322.2"><cite title="Internet Message Format">[RFC5322]</cite></a>. The field value is an HTTP-date, as defined in <a href="#http.date" title="Date/Time Formats">Section&nbsp;5.1</a>; it <em class="bcp14">MUST</em> be sent in rfc1123-date format.
    28952836      </p>
    2896       <div id="rfc.figure.u.45"></div><pre class="inline"><span id="rfc.iref.g.45"></span>  <a href="#header.date" class="smpl">Date</a> = <a href="#http.date" class="smpl">HTTP-date</a>
     2837      <div id="rfc.figure.u.43"></div><pre class="inline"><span id="rfc.iref.g.45"></span>  <a href="#header.date" class="smpl">Date</a> = <a href="#http.date" class="smpl">HTTP-date</a>
    28972838</pre><p id="rfc.section.9.10.p.3">An example is</p>
    2898       <div id="rfc.figure.u.46"></div><pre class="text">  Date: Tue, 15 Nov 1994 08:12:31 GMT
     2839      <div id="rfc.figure.u.44"></div><pre class="text">  Date: Tue, 15 Nov 1994 08:12:31 GMT
    28992840</pre><p id="rfc.section.9.10.p.5">Origin servers <em class="bcp14">MUST</em> include a Date header field in all responses, except in these cases:
    29002841      </p>
    … …  
    29222863      <h2 id="rfc.section.9.11"><a href="#rfc.section.9.11">9.11</a>&nbsp;<a id="header.expect" href="#header.expect">Expect</a></h2>
    29232864      <p id="rfc.section.9.11.p.1">The "Expect" header field is used to indicate that particular server behaviors are required by the client.</p>
    2924       <div id="rfc.figure.u.47"></div><pre class="inline"><span id="rfc.iref.g.46"></span><span id="rfc.iref.g.47"></span><span id="rfc.iref.g.48"></span><span id="rfc.iref.g.49"></span><span id="rfc.iref.g.50"></span>  <a href="#header.expect" class="smpl">Expect</a>       = 1#<a href="#header.expect" class="smpl">expectation</a>
     2865      <div id="rfc.figure.u.45"></div><pre class="inline"><span id="rfc.iref.g.46"></span><span id="rfc.iref.g.47"></span><span id="rfc.iref.g.48"></span><span id="rfc.iref.g.49"></span><span id="rfc.iref.g.50"></span>  <a href="#header.expect" class="smpl">Expect</a>       = 1#<a href="#header.expect" class="smpl">expectation</a>
    29252866 
    2926   <a href="#header.expect" class="smpl">expectation</a>  = <a href="#header.expect" class="smpl">expect-name</a> [ <a href="#core.rules" class="smpl">BWS</a> "=" <a href="#core.rules" class="smpl">BWS</a> <a href="#header.expect" class="smpl">expect-value</a> ]
    2927                              *( <a href="#core.rules" class="smpl">OWS</a> ";" [ <a href="#core.rules" class="smpl">OWS</a> <a href="#header.expect" class="smpl">expect-param</a> ] )
    2928   <a href="#header.expect" class="smpl">expect-param</a> = <a href="#header.expect" class="smpl">expect-name</a> [ <a href="#core.rules" class="smpl">BWS</a> "=" <a href="#core.rules" class="smpl">BWS</a> <a href="#header.expect" class="smpl">expect-value</a> ]
     2867  <a href="#header.expect" class="smpl">expectation</a>  = <a href="#header.expect" class="smpl">expect-name</a> [ <a href="#abnf.dependencies" class="smpl">BWS</a> "=" <a href="#abnf.dependencies" class="smpl">BWS</a> <a href="#header.expect" class="smpl">expect-value</a> ]
     2868                             *( <a href="#abnf.dependencies" class="smpl">OWS</a> ";" [ <a href="#abnf.dependencies" class="smpl">OWS</a> <a href="#header.expect" class="smpl">expect-param</a> ] )
     2869  <a href="#header.expect" class="smpl">expect-param</a> = <a href="#header.expect" class="smpl">expect-name</a> [ <a href="#abnf.dependencies" class="smpl">BWS</a> "=" <a href="#abnf.dependencies" class="smpl">BWS</a> <a href="#header.expect" class="smpl">expect-value</a> ]
    29292870 
    2930   <a href="#header.expect" class="smpl">expect-name</a>  = <a href="#core.rules" class="smpl">token</a>
    2931   <a href="#header.expect" class="smpl">expect-value</a> = <a href="#core.rules" class="smpl">token</a> / <a href="#core.rules" class="smpl">quoted-string</a>
     2871  <a href="#header.expect" class="smpl">expect-name</a>  = <a href="#abnf.dependencies" class="smpl">token</a>
     2872  <a href="#header.expect" class="smpl">expect-value</a> = <a href="#abnf.dependencies" class="smpl">token</a> / <a href="#abnf.dependencies" class="smpl">quoted-string</a>
    29322873</pre><p id="rfc.section.9.11.p.3">If all received Expect header field(s) are syntactically valid but contain an expectation that the recipient does not understand
    29332874         or cannot comply with, the recipient <em class="bcp14">MUST</em> respond with a <a href="#status.417" class="smpl">417 (Expectation Failed)</a> status code. A recipient of a syntactically invalid Expectation header field <em class="bcp14">MUST</em> respond with a <a href="#status.4xx" class="smpl">4xx</a> status code other than 417.
    … …  
    29372878      </p>
    29382879      <ul class="empty">
    2939          <li>The "100-continue" expectation is defined <a href="p1-messaging.html#use.of.the.100.status" title="Use of the 100 (Continue) Status">Section 6.4.3</a> of <a href="#Part1" id="rfc.xref.Part1.50"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. It does not support any expect-params.
     2880         <li>The "100-continue" expectation is defined <a href="p1-messaging.html#use.of.the.100.status" title="Use of the 100 (Continue) Status">Section 6.4.3</a> of <a href="#Part1" id="rfc.xref.Part1.36"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. It does not support any expect-params.
    29402881         </li>
    29412882      </ul>
    … …  
    29502891      <p id="rfc.section.9.12.p.1">The "From" header field, if given, <em class="bcp14">SHOULD</em> contain an Internet e-mail address for the human user who controls the requesting user agent. The address <em class="bcp14">SHOULD</em> be machine-usable, as defined by "mailbox" in <a href="http://tools.ietf.org/html/rfc5322#section-3.4">Section 3.4</a> of <a href="#RFC5322" id="rfc.xref.RFC5322.3"><cite title="Internet Message Format">[RFC5322]</cite></a>:
    29512892      </p>
    2952       <div id="rfc.figure.u.48"></div><pre class="inline"><span id="rfc.iref.g.51"></span>  <a href="#header.from" class="smpl">From</a>    = <a href="#header.from" class="smpl">mailbox</a>
     2893      <div id="rfc.figure.u.46"></div><pre class="inline"><span id="rfc.iref.g.51"></span>  <a href="#header.from" class="smpl">From</a>    = <a href="#header.from" class="smpl">mailbox</a>
    29532894 
    29542895  <a href="#header.from" class="smpl">mailbox</a> = &lt;mailbox, defined in <a href="#RFC5322" id="rfc.xref.RFC5322.4"><cite title="Internet Message Format">[RFC5322]</cite></a>, <a href="http://tools.ietf.org/html/rfc5322#section-3.4">Section 3.4</a>&gt;
    29552896</pre><p id="rfc.section.9.12.p.3">An example is:</p>
    2956       <div id="rfc.figure.u.49"></div><pre class="text">  From: webmaster@example.org
     2897      <div id="rfc.figure.u.47"></div><pre class="text">  From: webmaster@example.org
    29572898</pre><p id="rfc.section.9.12.p.5">This header field <em class="bcp14">MAY</em> be used for logging purposes and as a means for identifying the source of invalid or unwanted requests. It <em class="bcp14">SHOULD NOT</em> be used as an insecure form of access protection. The interpretation of this field is that the request is being performed
    29582899         on behalf of the person given, who accepts responsibility for the method performed. In particular, robot agents <em class="bcp14">SHOULD</em> include this header field so that the person responsible for running the robot can be contacted if problems occur on the receiving
    … …  
    29712912      <p id="rfc.section.9.13.p.1">The "Location" header field <em class="bcp14">MAY</em> be sent in responses to refer to a specific resource in accordance with the semantics of the status code.
    29722913      </p>
    2973       <div id="rfc.figure.u.50"></div><pre class="inline"><span id="rfc.iref.g.52"></span>  <a href="#header.location" class="smpl">Location</a> = <a href="#abnf.dependencies" class="smpl">URI-reference</a>
     2914      <div id="rfc.figure.u.48"></div><pre class="inline"><span id="rfc.iref.g.52"></span>  <a href="#header.location" class="smpl">Location</a> = <a href="#abnf.dependencies" class="smpl">URI-reference</a>
    29742915</pre><p id="rfc.section.9.13.p.3">For <a href="#status.201" class="smpl">201 (Created)</a> responses, the Location is the URI of the new resource which was created by the request. For <a href="#status.3xx" class="smpl">3xx (Redirection)</a> responses, the location <em class="bcp14">SHOULD</em> indicate the server's preferred URI for automatic redirection to the resource.
    29752916      </p>
    … …  
    29772918         then the original URI's fragment identifier is added to the final value.
    29782919      </p>
    2979       <div id="rfc.figure.u.51"></div>
     2920      <div id="rfc.figure.u.49"></div>
    29802921      <p>For example, the original URI "http://www.example.org/~tim", combined with a field value given as:</p>  <pre class="text">  Location: /pub/WWW/People.html#tim
    29812922</pre>  <p>would result in a final value of "http://www.example.org/pub/WWW/People.html#tim"</p>
    2982       <div id="rfc.figure.u.52"></div>
     2923      <div id="rfc.figure.u.50"></div>
    29832924      <p>An original URI "http://www.example.org/index.html#larry", combined with a field value given as:</p>  <pre class="text">  Location: http://www.example.net/index.html
    29842925</pre>  <p>would result in a final value of "http://www.example.net/index.html#larry", preserving the original fragment identifier.</p>
    29852926      <div class="note" id="rfc.section.9.13.p.7">
    29862927         <p> <b>Note:</b> Some recipients attempt to recover from Location fields that are not valid URI references. This specification does not mandate
    2987             or define such processing, but does allow it (see <a href="#intro.conformance.and.error.handling" title="Conformance and Error Handling">Section&nbsp;1.2</a>).
     2928            or define such processing, but does allow it.
    29882929         </p>
    29892930      </div>
    … …  
    30032944         to trace a request which appears to be failing or looping mid-chain.
    30042945      </p>
    3005       <div id="rfc.figure.u.53"></div><pre class="inline"><span id="rfc.iref.g.53"></span>  <a href="#header.max-forwards" class="smpl">Max-Forwards</a> = 1*<a href="#notation" class="smpl">DIGIT</a>
     2946      <div id="rfc.figure.u.51"></div><pre class="inline"><span id="rfc.iref.g.53"></span>  <a href="#header.max-forwards" class="smpl">Max-Forwards</a> = 1*<a href="#abnf.dependencies" class="smpl">DIGIT</a>
    30062947</pre><p id="rfc.section.9.14.p.3">The Max-Forwards value is a decimal integer indicating the remaining number of times this request message can be forwarded.</p>
    30072948      <p id="rfc.section.9.14.p.4">Each recipient of a TRACE or OPTIONS request containing a Max-Forwards header field <em class="bcp14">MUST</em> check and update its value prior to forwarding the request. If the received value is zero (0), the recipient <em class="bcp14">MUST NOT</em> forward the request; instead, it <em class="bcp14">MUST</em> respond as the final recipient. If the received Max-Forwards value is greater than zero, then the forwarded message <em class="bcp14">MUST</em> contain an updated Max-Forwards field with a value decremented by one (1).
    … …  
    30232964         non-HTTP URIs (e.g., FTP).
    30242965      </p>
    3025       <div id="rfc.figure.u.54"></div><pre class="inline"><span id="rfc.iref.g.54"></span>  <a href="#header.referer" class="smpl">Referer</a> = <a href="#abnf.dependencies" class="smpl">absolute-URI</a> / <a href="#abnf.dependencies" class="smpl">partial-URI</a>
     2966      <div id="rfc.figure.u.52"></div><pre class="inline"><span id="rfc.iref.g.54"></span>  <a href="#header.referer" class="smpl">Referer</a> = <a href="#abnf.dependencies" class="smpl">absolute-URI</a> / <a href="#abnf.dependencies" class="smpl">partial-URI</a>
    30262967</pre><p id="rfc.section.9.15.p.5">Example:</p>
    3027       <div id="rfc.figure.u.55"></div><pre class="text">  Referer: http://www.example.org/hypertext/Overview.html
    3028 </pre><p id="rfc.section.9.15.p.7">If the field value is a relative URI, it <em class="bcp14">SHOULD</em> be interpreted relative to the effective request URI. The URI <em class="bcp14">MUST NOT</em> include a fragment. See <a href="#encoding.sensitive.information.in.uris" title="Encoding Sensitive Information in URIs">Section&nbsp;11.2</a> for security considerations.
     2968      <div id="rfc.figure.u.53"></div><pre class="text">  Referer: http://www.example.org/hypertext/Overview.html
     2969</pre><p id="rfc.section.9.15.p.7">If the field value is a relative URI, it <em class="bcp14">SHOULD</em> be interpreted relative to the effective request URI. The URI <em class="bcp14">MUST NOT</em> include a fragment. See <a href="#encoding.sensitive.information.in.uris" title="Encoding Sensitive Information in URIs">Section&nbsp;12.2</a> for security considerations.
    30292970      </p>
    30302971      <div id="rfc.iref.r.3"></div>
    … …  
    30352976      </p>
    30362977      <p id="rfc.section.9.16.p.2">The value of this field can be either an HTTP-date or an integer number of seconds (in decimal) after the time of the response.</p>
    3037       <div id="rfc.figure.u.56"></div><pre class="inline"><span id="rfc.iref.g.55"></span>  <a href="#header.retry-after" class="smpl">Retry-After</a> = <a href="#http.date" class="smpl">HTTP-date</a> / <a href="#rule.delta-seconds" class="smpl">delta-seconds</a>
     2978      <div id="rfc.figure.u.54"></div><pre class="inline"><span id="rfc.iref.g.55"></span>  <a href="#header.retry-after" class="smpl">Retry-After</a> = <a href="#http.date" class="smpl">HTTP-date</a> / <a href="#rule.delta-seconds" class="smpl">delta-seconds</a>
    30382979</pre><div id="rule.delta-seconds">
    30392980         <p id="rfc.section.9.16.p.4">  Time spans are non-negative decimal integers, representing time in seconds.</p>
    30402981      </div>
    3041       <div id="rfc.figure.u.57"></div><pre class="inline"><span id="rfc.iref.g.56"></span>  <a href="#rule.delta-seconds" class="smpl">delta-seconds</a>  = 1*<a href="#notation" class="smpl">DIGIT</a>
     2982      <div id="rfc.figure.u.55"></div><pre class="inline"><span id="rfc.iref.g.56"></span>  <a href="#rule.delta-seconds" class="smpl">delta-seconds</a>  = 1*<a href="#abnf.dependencies" class="smpl">DIGIT</a>
    30422983</pre><p id="rfc.section.9.16.p.6">Two examples of its use are</p>
    3043       <div id="rfc.figure.u.58"></div><pre class="text">  Retry-After: Fri, 31 Dec 1999 23:59:59 GMT
     2984      <div id="rfc.figure.u.56"></div><pre class="text">  Retry-After: Fri, 31 Dec 1999 23:59:59 GMT
    30442985  Retry-After: 120
    30452986</pre><p id="rfc.section.9.16.p.8">In the latter example, the delay is 2 minutes.</p>
    … …  
    30482989      <h2 id="rfc.section.9.17"><a href="#rfc.section.9.17">9.17</a>&nbsp;<a id="header.server" href="#header.server">Server</a></h2>
    30492990      <p id="rfc.section.9.17.p.1">The "Server" header field contains information about the software used by the origin server to handle the request.</p>
    3050       <p id="rfc.section.9.17.p.2">The field can contain multiple product tokens (<a href="#product.tokens" title="Product Tokens">Section&nbsp;5.2</a>) and comments (<a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a> of <a href="#Part1" id="rfc.xref.Part1.51"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) identifying the server and any significant subproducts. The product tokens are listed in order of their significance for
     2991      <p id="rfc.section.9.17.p.2">The field can contain multiple product tokens (<a href="#product.tokens" title="Product Tokens">Section&nbsp;5.2</a>) and comments (<a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a> of <a href="#Part1" id="rfc.xref.Part1.37"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) identifying the server and any significant subproducts. The product tokens are listed in order of their significance for
    30512992         identifying the application.
    30522993      </p>
    3053       <div id="rfc.figure.u.59"></div><pre class="inline"><span id="rfc.iref.g.57"></span>  <a href="#header.server" class="smpl">Server</a> = <a href="#product.tokens" class="smpl">product</a> *( <a href="#core.rules" class="smpl">RWS</a> ( <a href="#product.tokens" class="smpl">product</a> / <a href="#abnf.dependencies" class="smpl">comment</a> ) )
     2994      <div id="rfc.figure.u.57"></div><pre class="inline"><span id="rfc.iref.g.57"></span>  <a href="#header.server" class="smpl">Server</a> = <a href="#product.tokens" class="smpl">product</a> *( <a href="#abnf.dependencies" class="smpl">RWS</a> ( <a href="#product.tokens" class="smpl">product</a> / <a href="#abnf.dependencies" class="smpl">comment</a> ) )
    30542995</pre><p id="rfc.section.9.17.p.4">Example:</p>
    3055       <div id="rfc.figure.u.60"></div><pre class="text">  Server: CERN/3.0 libwww/2.17
    3056 </pre><p id="rfc.section.9.17.p.6">If the response is being forwarded through a proxy, the proxy application <em class="bcp14">MUST NOT</em> modify the <a href="#header.server" class="smpl">Server</a> header field. Instead, it <em class="bcp14">MUST</em> include a <a href="p1-messaging.html#header.via" class="smpl">Via</a> field (as described in <a href="p1-messaging.html#header.via" title="Via">Section 6.2</a> of <a href="#Part1" id="rfc.xref.Part1.52"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
     2996      <div id="rfc.figure.u.58"></div><pre class="text">  Server: CERN/3.0 libwww/2.17
     2997</pre><p id="rfc.section.9.17.p.6">If the response is being forwarded through a proxy, the proxy application <em class="bcp14">MUST NOT</em> modify the <a href="#header.server" class="smpl">Server</a> header field. Instead, it <em class="bcp14">MUST</em> include a <a href="p1-messaging.html#header.via" class="smpl">Via</a> field (as described in <a href="p1-messaging.html#header.via" title="Via">Section 6.2</a> of <a href="#Part1" id="rfc.xref.Part1.38"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
    30572998      </p>
    30582999      <div class="note" id="rfc.section.9.17.p.7">
    … …  
    30703011         user agent limitations.
    30713012      </p>
    3072       <p id="rfc.section.9.18.p.3">The field can contain multiple product tokens (<a href="#product.tokens" title="Product Tokens">Section&nbsp;5.2</a>) and comments (<a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a> of <a href="#Part1" id="rfc.xref.Part1.53"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) identifying the agent and its significant subproducts. By convention, the product tokens are listed in order of their significance
     3013      <p id="rfc.section.9.18.p.3">The field can contain multiple product tokens (<a href="#product.tokens" title="Product Tokens">Section&nbsp;5.2</a>) and comments (<a href="p1-messaging.html#header.fields" title="Header Fields">Section 3.2</a> of <a href="#Part1" id="rfc.xref.Part1.39"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) identifying the agent and its significant subproducts. By convention, the product tokens are listed in order of their significance
    30733014         for identifying the application.
    30743015      </p>
    … …  
    30813022         doing so makes the field value more difficult to parse.
    30823023      </p>
    3083       <div id="rfc.figure.u.61"></div><pre class="inline"><span id="rfc.iref.g.58"></span>  <a href="#header.user-agent" class="smpl">User-Agent</a> = <a href="#product.tokens" class="smpl">product</a> *( <a href="#core.rules" class="smpl">RWS</a> ( <a href="#product.tokens" class="smpl">product</a> / <a href="#abnf.dependencies" class="smpl">comment</a> ) )
     3024      <div id="rfc.figure.u.59"></div><pre class="inline"><span id="rfc.iref.g.58"></span>  <a href="#header.user-agent" class="smpl">User-Agent</a> = <a href="#product.tokens" class="smpl">product</a> *( <a href="#abnf.dependencies" class="smpl">RWS</a> ( <a href="#product.tokens" class="smpl">product</a> / <a href="#abnf.dependencies" class="smpl">comment</a> ) )
    30843025</pre><p id="rfc.section.9.18.p.7">Example:</p>
    3085       <div id="rfc.figure.u.62"></div><pre class="text">  User-Agent: CERN-LineMode/2.15 libwww/2.17b3
     3026      <div id="rfc.figure.u.60"></div><pre class="text">  User-Agent: CERN-LineMode/2.15 libwww/2.17b3
    30863027</pre><h1 id="rfc.section.10"><a href="#rfc.section.10">10.</a>&nbsp;<a id="IANA.considerations" href="#IANA.considerations">IANA Considerations</a></h1>
    30873028      <h2 id="rfc.section.10.1"><a href="#rfc.section.10.1">10.1</a>&nbsp;<a id="method.registration" href="#method.registration">Method Registry</a></h2>
    … …  
    35673508                  <td class="left">compress</td>
    35683509                  <td class="left">UNIX "compress" program method</td>
    3569                   <td class="left"> <a href="p1-messaging.html#compress.coding" title="Compress Coding">Section 4.2.1</a> of <a href="#Part1" id="rfc.xref.Part1.54"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>
     3510                  <td class="left"> <a href="p1-messaging.html#compress.coding" title="Compress Coding">Section 4.2.1</a> of <a href="#Part1" id="rfc.xref.Part1.40"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>
    35703511                  </td>
    35713512               </tr>
    … …  
    35743515                  <td class="left">"deflate" compression mechanism (<a href="#RFC1951" id="rfc.xref.RFC1951.1"><cite title="DEFLATE Compressed Data Format Specification version 1.3">[RFC1951]</cite></a>) used inside the "zlib" data format (<a href="#RFC1950" id="rfc.xref.RFC1950.1"><cite title="ZLIB Compressed Data Format Specification version 3.3">[RFC1950]</cite></a>)
    35753516                  </td>
    3576                   <td class="left"> <a href="p1-messaging.html#deflate.coding" title="Deflate Coding">Section 4.2.2</a> of <a href="#Part1" id="rfc.xref.Part1.55"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>
     3517                  <td class="left"> <a href="p1-messaging.html#deflate.coding" title="Deflate Coding">Section 4.2.2</a> of <a href="#Part1" id="rfc.xref.Part1.41"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>
    35773518                  </td>
    35783519               </tr>
    … …  
    35803521                  <td class="left">gzip</td>
    35813522                  <td class="left">Same as GNU zip <a href="#RFC1952" id="rfc.xref.RFC1952.1"><cite title="GZIP file format specification version 4.3">[RFC1952]</cite></a></td>
    3582                   <td class="left"> <a href="p1-messaging.html#gzip.coding" title="Gzip Coding">Section 4.2.3</a> of <a href="#Part1" id="rfc.xref.Part1.56"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>
     3523                  <td class="left"> <a href="p1-messaging.html#gzip.coding" title="Gzip Coding">Section 4.2.3</a> of <a href="#Part1" id="rfc.xref.Part1.42"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>
    35833524                  </td>
    35843525               </tr>
    … …  
    35933534         </table>
    35943535      </div>
    3595       <h1 id="rfc.section.11"><a href="#rfc.section.11">11.</a>&nbsp;<a id="security.considerations" href="#security.considerations">Security Considerations</a></h1>
    3596       <p id="rfc.section.11.p.1">This section is meant to inform application developers, information providers, and users of the security limitations in HTTP/1.1
     3536      <h1 id="rfc.section.11"><a href="#rfc.section.11">11.</a>&nbsp;<a id="abnf.dependencies" href="#abnf.dependencies">ABNF Rules Defined Elsewhere</a></h1>
     3537      <p id="rfc.section.11.p.1">This specification uses the Augmented Backus-Naur Form (ABNF) notation of <a href="#RFC5234" id="rfc.xref.RFC5234.2"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a> with the list rule extension defined in <a href="p1-messaging.html#notation" title="Syntax Notation">Section 1.2</a> of <a href="#Part1" id="rfc.xref.Part1.43"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. <a href="#collected.abnf" title="Collected ABNF">Appendix&nbsp;D</a> shows the collected ABNF with the list rule expanded.
     3538      </p>
     3539      <p id="rfc.section.11.p.2">The following core rules are included by reference, as defined in <a href="#RFC5234" id="rfc.xref.RFC5234.3"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a>, <a href="http://tools.ietf.org/html/rfc5234#appendix-B.1">Appendix B.1</a>: ALPHA (letters), CR (carriage return), CRLF (CR LF), CTL (controls), DIGIT (decimal 0-9), DQUOTE (double quote), HEXDIG
     3540         (hexadecimal 0-9/A-F/a-f), HTAB (horizontal tab), LF (line feed), OCTET (any 8-bit sequence of data), SP (space), and VCHAR
     3541         (any visible US-ASCII character).
     3542      </p>
     3543      <p id="rfc.section.11.p.3">The ABNF rules below are defined in other parts:</p>
     3544      <div id="rfc.figure.u.61"></div><pre class="inline">  <a href="#abnf.dependencies" class="smpl">BWS</a>           = &lt;BWS, defined in <a href="#Part1" id="rfc.xref.Part1.44"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
     3545  <a href="#abnf.dependencies" class="smpl">OWS</a>           = &lt;OWS, defined in <a href="#Part1" id="rfc.xref.Part1.45"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
     3546  <a href="#abnf.dependencies" class="smpl">RWS</a>           = &lt;RWS, defined in <a href="#Part1" id="rfc.xref.Part1.46"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
     3547  <a href="#abnf.dependencies" class="smpl">URI-reference</a> = &lt;URI-reference, defined in <a href="#Part1" id="rfc.xref.Part1.47"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.8</a>&gt;
     3548  <a href="#abnf.dependencies" class="smpl">absolute-URI</a>  = &lt;absolute-URI, defined in <a href="#Part1" id="rfc.xref.Part1.48"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.8</a>&gt;
     3549  <a href="#abnf.dependencies" class="smpl">partial-URI</a>   = &lt;partial-URI, defined in <a href="#Part1" id="rfc.xref.Part1.49"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.8</a>&gt;
     3550  <a href="#abnf.dependencies" class="smpl">quoted-string</a> = &lt;quoted-string, defined in <a href="#Part1" id="rfc.xref.Part1.50"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
     3551  <a href="#abnf.dependencies" class="smpl">qvalue</a>        = &lt;qvalue, defined in <a href="#Part1" id="rfc.xref.Part1.51"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#quality.values" title="Quality Values">Section 4.3.1</a>&gt;
     3552  <a href="#abnf.dependencies" class="smpl">token</a>         = &lt;token, defined in <a href="#Part1" id="rfc.xref.Part1.52"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
     3553  <a href="#abnf.dependencies" class="smpl">word</a>          = &lt;word, defined in <a href="#Part1" id="rfc.xref.Part1.53"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
     3554  <a href="#abnf.dependencies" class="smpl">comment</a>       = &lt;comment, defined in <a href="#Part1" id="rfc.xref.Part1.54"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
     3555</pre><h1 id="rfc.section.12"><a href="#rfc.section.12">12.</a>&nbsp;<a id="security.considerations" href="#security.considerations">Security Considerations</a></h1>
     3556      <p id="rfc.section.12.p.1">This section is meant to inform application developers, information providers, and users of the security limitations in HTTP/1.1
    35973557         as described by this document. The discussion does not include definitive solutions to the problems revealed, though it does
    35983558         make some suggestions for reducing security risks.
    35993559      </p>
    3600       <h2 id="rfc.section.11.1"><a href="#rfc.section.11.1">11.1</a>&nbsp;<a id="security.sensitive" href="#security.sensitive">Transfer of Sensitive Information</a></h2>
    3601       <p id="rfc.section.11.1.p.1">Like any generic data transfer protocol, HTTP cannot regulate the content of the data that is transferred, nor is there any
     3560      <h2 id="rfc.section.12.1"><a href="#rfc.section.12.1">12.1</a>&nbsp;<a id="security.sensitive" href="#security.sensitive">Transfer of Sensitive Information</a></h2>
     3561      <p id="rfc.section.12.1.p.1">Like any generic data transfer protocol, HTTP cannot regulate the content of the data that is transferred, nor is there any
    36023562         a priori method of determining the sensitivity of any particular piece of information within the context of any given request.
    36033563         Therefore, applications <em class="bcp14">SHOULD</em> supply as much control over this information as possible to the provider of that information. Four header fields are worth
    36043564         special mention in this context: <a href="#header.server" class="smpl">Server</a>, <a href="p1-messaging.html#header.via" class="smpl">Via</a>, <a href="#header.referer" class="smpl">Referer</a> and <a href="#header.from" class="smpl">From</a>.
    36053565      </p>
    3606       <p id="rfc.section.11.1.p.2">Revealing the specific software version of the server might allow the server machine to become more vulnerable to attacks
     3566      <p id="rfc.section.12.1.p.2">Revealing the specific software version of the server might allow the server machine to become more vulnerable to attacks
    36073567         against software that is known to contain security holes. Implementers <em class="bcp14">SHOULD</em> make the <a href="#header.server" class="smpl">Server</a> header field a configurable option.
    36083568      </p>
    3609       <p id="rfc.section.11.1.p.3">Proxies which serve as a portal through a network firewall <em class="bcp14">SHOULD</em> take special precautions regarding the transfer of header information that identifies the hosts behind the firewall. In particular,
     3569      <p id="rfc.section.12.1.p.3">Proxies which serve as a portal through a network firewall <em class="bcp14">SHOULD</em> take special precautions regarding the transfer of header information that identifies the hosts behind the firewall. In particular,
    36103570         they <em class="bcp14">SHOULD</em> remove, or replace with sanitized versions, any <a href="p1-messaging.html#header.via" class="smpl">Via</a> fields generated behind the firewall.
    36113571      </p>
    3612       <p id="rfc.section.11.1.p.4">The <a href="#header.referer" class="smpl">Referer</a> header field allows reading patterns to be studied and reverse links drawn. Although it can be very useful, its power can
     3572      <p id="rfc.section.12.1.p.4">The <a href="#header.referer" class="smpl">Referer</a> header field allows reading patterns to be studied and reverse links drawn. Although it can be very useful, its power can
    36133573         be abused if user details are not separated from the information contained in the Referer. Even when the personal information
    36143574         has been removed, the Referer header field might indicate a private document's URI whose publication would be inappropriate.
    36153575      </p>
    3616       <p id="rfc.section.11.1.p.5">The information sent in the <a href="#header.from" class="smpl">From</a> field might conflict with the user's privacy interests or their site's security policy, and hence it <em class="bcp14">SHOULD NOT</em> be transmitted without the user being able to disable, enable, and modify the contents of the field. The user <em class="bcp14">MUST</em> be able to set the contents of this field within a user preference or application defaults configuration.
    3617       </p>
    3618       <p id="rfc.section.11.1.p.6">We suggest, though do not require, that a convenient toggle interface be provided for the user to enable or disable the sending
     3576      <p id="rfc.section.12.1.p.5">The information sent in the <a href="#header.from" class="smpl">From</a> field might conflict with the user's privacy interests or their site's security policy, and hence it <em class="bcp14">SHOULD NOT</em> be transmitted without the user being able to disable, enable, and modify the contents of the field. The user <em class="bcp14">MUST</em> be able to set the contents of this field within a user preference or application defaults configuration.
     3577      </p>
     3578      <p id="rfc.section.12.1.p.6">We suggest, though do not require, that a convenient toggle interface be provided for the user to enable or disable the sending
    36193579         of <a href="#header.from" class="smpl">From</a> and <a href="#header.referer" class="smpl">Referer</a> information.
    36203580      </p>
    3621       <p id="rfc.section.11.1.p.7">The <a href="#header.user-agent" class="smpl">User-Agent</a> (<a href="#header.user-agent" id="rfc.xref.header.user-agent.4" title="User-Agent">Section&nbsp;9.18</a>) or <a href="#header.server" class="smpl">Server</a> (<a href="#header.server" id="rfc.xref.header.server.3" title="Server">Section&nbsp;9.17</a>) header fields can sometimes be used to determine that a specific client or server has a particular security hole which might
     3581      <p id="rfc.section.12.1.p.7">The <a href="#header.user-agent" class="smpl">User-Agent</a> (<a href="#header.user-agent" id="rfc.xref.header.user-agent.4" title="User-Agent">Section&nbsp;9.18</a>) or <a href="#header.server" class="smpl">Server</a> (<a href="#header.server" id="rfc.xref.header.server.3" title="Server">Section&nbsp;9.17</a>) header fields can sometimes be used to determine that a specific client or server has a particular security hole which might
    36223582         be exploited. Unfortunately, this same information is often used for other valuable purposes for which HTTP currently has
    36233583         no better mechanism.
    36243584      </p>
    3625       <p id="rfc.section.11.1.p.8">Furthermore, the <a href="#header.user-agent" class="smpl">User-Agent</a> header field might contain enough entropy to be used, possibly in conjunction with other material, to uniquely identify the
     3585      <p id="rfc.section.12.1.p.8">Furthermore, the <a href="#header.user-agent" class="smpl">User-Agent</a> header field might contain enough entropy to be used, possibly in conjunction with other material, to uniquely identify the
    36263586         user.
    36273587      </p>
    3628       <p id="rfc.section.11.1.p.9">Some request methods, like TRACE (<a href="#TRACE" id="rfc.xref.TRACE.3" title="TRACE">Section&nbsp;2.3.7</a>), expose information that was sent in request header fields within the body of their response. Clients <em class="bcp14">SHOULD</em> be careful with sensitive information, like Cookies, Authorization credentials, and other header fields that might be used
     3588      <p id="rfc.section.12.1.p.9">Some request methods, like TRACE (<a href="#TRACE" id="rfc.xref.TRACE.3" title="TRACE">Section&nbsp;2.3.7</a>), expose information that was sent in request header fields within the body of their response. Clients <em class="bcp14">SHOULD</em> be careful with sensitive information, like Cookies, Authorization credentials, and other header fields that might be used
    36293589         to collect data from the client.
    36303590      </p>
    3631       <h2 id="rfc.section.11.2"><a href="#rfc.section.11.2">11.2</a>&nbsp;<a id="encoding.sensitive.information.in.uris" href="#encoding.sensitive.information.in.uris">Encoding Sensitive Information in URIs</a></h2>
    3632       <p id="rfc.section.11.2.p.1">Because the source of a link might be private information or might reveal an otherwise private information source, it is strongly
     3591      <h2 id="rfc.section.12.2"><a href="#rfc.section.12.2">12.2</a>&nbsp;<a id="encoding.sensitive.information.in.uris" href="#encoding.sensitive.information.in.uris">Encoding Sensitive Information in URIs</a></h2>
     3592      <p id="rfc.section.12.2.p.1">Because the source of a link might be private information or might reveal an otherwise private information source, it is strongly
    36333593         recommended that the user be able to select whether or not the <a href="#header.referer" class="smpl">Referer</a> field is sent. For example, a browser client could have a toggle switch for browsing openly/anonymously, which would respectively
    36343594         enable/disable the sending of Referer and From information.
    36353595      </p>
    3636       <p id="rfc.section.11.2.p.2">Clients <em class="bcp14">SHOULD NOT</em> include a <a href="#header.referer" class="smpl">Referer</a> header field in a (non-secure) HTTP request if the referring page was transferred with a secure protocol.
    3637       </p>
    3638       <p id="rfc.section.11.2.p.3">Authors of services <em class="bcp14">SHOULD NOT</em> use GET-based forms for the submission of sensitive data because that data will be placed in the request-target. Many existing
     3596      <p id="rfc.section.12.2.p.2">Clients <em class="bcp14">SHOULD NOT</em> include a <a href="#header.referer" class="smpl">Referer</a> header field in a (non-secure) HTTP request if the referring page was transferred with a secure protocol.
     3597      </p>
     3598      <p id="rfc.section.12.2.p.3">Authors of services <em class="bcp14">SHOULD NOT</em> use GET-based forms for the submission of sensitive data because that data will be placed in the request-target. Many existing
    36393599         servers, proxies, and user agents log or display the request-target in places where it might be visible to third parties.
    36403600         Such services can use POST-based form submission instead.
    36413601      </p>
    3642       <h2 id="rfc.section.11.3"><a href="#rfc.section.11.3">11.3</a>&nbsp;<a id="location.spoofing-leakage" href="#location.spoofing-leakage">Location Header Fields: Spoofing and Information Leakage</a></h2>
    3643       <p id="rfc.section.11.3.p.1">If a single server supports multiple organizations that do not trust one another, then it <em class="bcp14">MUST</em> check the values of <a href="#header.location" class="smpl">Location</a> and <a href="#header.content-location" class="smpl">Content-Location</a> header fields in responses that are generated under control of said organizations to make sure that they do not attempt to
     3602      <h2 id="rfc.section.12.3"><a href="#rfc.section.12.3">12.3</a>&nbsp;<a id="location.spoofing-leakage" href="#location.spoofing-leakage">Location Header Fields: Spoofing and Information Leakage</a></h2>
     3603      <p id="rfc.section.12.3.p.1">If a single server supports multiple organizations that do not trust one another, then it <em class="bcp14">MUST</em> check the values of <a href="#header.location" class="smpl">Location</a> and <a href="#header.content-location" class="smpl">Content-Location</a> header fields in responses that are generated under control of said organizations to make sure that they do not attempt to
    36443604         invalidate resources over which they have no authority.
    36453605      </p>
    3646       <p id="rfc.section.11.3.p.2">Furthermore, appending the fragment identifier from one URI to another one obtained from a <a href="#header.location" class="smpl">Location</a> header field might leak confidential information to the target server — although the fragment identifier is not transmitted
     3606      <p id="rfc.section.12.3.p.2">Furthermore, appending the fragment identifier from one URI to another one obtained from a <a href="#header.location" class="smpl">Location</a> header field might leak confidential information to the target server — although the fragment identifier is not transmitted
    36473607         in the final request, it might be visible to the user agent through other means, such as scripting.
    36483608      </p>
    3649       <h2 id="rfc.section.11.4"><a href="#rfc.section.11.4">11.4</a>&nbsp;Security Considerations for CONNECT
     3609      <h2 id="rfc.section.12.4"><a href="#rfc.section.12.4">12.4</a>&nbsp;Security Considerations for CONNECT
    36503610      </h2>
    3651       <p id="rfc.section.11.4.p.1">Since tunneled data is opaque to the proxy, there are additional risks to tunneling to other well-known or reserved ports.
     3611      <p id="rfc.section.12.4.p.1">Since tunneled data is opaque to the proxy, there are additional risks to tunneling to other well-known or reserved ports.
    36523612         A HTTP client CONNECTing to port 25 could relay spam via SMTP, for example. As such, proxies <em class="bcp14">SHOULD</em> restrict CONNECT access to a small number of known ports.
    36533613      </p>
    3654       <h2 id="rfc.section.11.5"><a href="#rfc.section.11.5">11.5</a>&nbsp;<a id="privacy.issues.connected.to.accept.header.fields" href="#privacy.issues.connected.to.accept.header.fields">Privacy Issues Connected to Accept Header Fields</a></h2>
    3655       <p id="rfc.section.11.5.p.1">Accept header fields can reveal information about the user to all servers which are accessed. The <a href="#header.accept-language" class="smpl">Accept-Language</a> header field in particular can reveal information the user would consider to be of a private nature, because the understanding
     3614      <h2 id="rfc.section.12.5"><a href="#rfc.section.12.5">12.5</a>&nbsp;<a id="privacy.issues.connected.to.accept.header.fields" href="#privacy.issues.connected.to.accept.header.fields">Privacy Issues Connected to Accept Header Fields</a></h2>
     3615      <p id="rfc.section.12.5.p.1">Accept header fields can reveal information about the user to all servers which are accessed. The <a href="#header.accept-language" class="smpl">Accept-Language</a> header field in particular can reveal information the user would consider to be of a private nature, because the understanding
    36563616         of particular languages is often strongly correlated to the membership of a particular ethnic group. User agents which offer
    36573617         the option to configure the contents of an Accept-Language header field to be sent in every request are strongly encouraged
    36583618         to let the configuration process include a message which makes the user aware of the loss of privacy involved.
    36593619      </p>
    3660       <p id="rfc.section.11.5.p.2">An approach that limits the loss of privacy would be for a user agent to omit the sending of Accept-Language header fields
     3620      <p id="rfc.section.12.5.p.2">An approach that limits the loss of privacy would be for a user agent to omit the sending of Accept-Language header fields
    36613621         by default, and to ask the user whether or not to start sending Accept-Language header fields to a server if it detects, by
    36623622         looking for any <a href="p6-cache.html#header.vary" class="smpl">Vary</a> header fields generated by the server, that such sending could improve the quality of service.
    36633623      </p>
    3664       <p id="rfc.section.11.5.p.3">Elaborate user-customized accept header fields sent in every request, in particular if these include quality values, can be
     3624      <p id="rfc.section.12.5.p.3">Elaborate user-customized accept header fields sent in every request, in particular if these include quality values, can be
    36653625         used by servers as relatively reliable and long-lived user identifiers. Such user identifiers would allow content providers
    36663626         to do click-trail tracking, and would allow collaborating content providers to match cross-server click-trails or form submissions
    … …  
    36713631         field configurability <em class="bcp14">SHOULD</em> warn users about the loss of privacy which can be involved.
    36723632      </p>
    3673       <h1 id="rfc.section.12"><a href="#rfc.section.12">12.</a>&nbsp;<a id="acks" href="#acks">Acknowledgments</a></h1>
    3674       <p id="rfc.section.12.p.1">See <a href="p1-messaging.html#acks" title="Acknowledgments">Section 9</a> of <a href="#Part1" id="rfc.xref.Part1.57"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
    3675       </p>
    3676       <h1 id="rfc.references"><a id="rfc.section.13" href="#rfc.section.13">13.</a> References
     3633      <h1 id="rfc.section.13"><a href="#rfc.section.13">13.</a>&nbsp;<a id="acks" href="#acks">Acknowledgments</a></h1>
     3634      <p id="rfc.section.13.p.1">See <a href="p1-messaging.html#acks" title="Acknowledgments">Section 9</a> of <a href="#Part1" id="rfc.xref.Part1.55"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>.
     3635      </p>
     3636      <h1 id="rfc.references"><a id="rfc.section.14" href="#rfc.section.14">14.</a> References
    36773637      </h1>
    3678       <h2 id="rfc.references.1"><a href="#rfc.section.13.1" id="rfc.section.13.1">13.1</a> Normative References
     3638      <h2 id="rfc.references.1"><a href="#rfc.section.14.1" id="rfc.section.14.1">14.1</a> Normative References
    36793639      </h2>
    36803640      <table>                             
    … …  
    37303690         </tr>
    37313691         <tr>
    3732             <td class="reference"><b id="RFC2119">[RFC2119]</b></td>
    3733             <td class="top"><a href="mailto:sob@harvard.edu" title="Harvard University">Bradner, S.</a>, “<a href="http://tools.ietf.org/html/rfc2119">Key words for use in RFCs to Indicate Requirement Levels</a>”, BCP&nbsp;14, RFC&nbsp;2119, March&nbsp;1997.
    3734             </td>
    3735          </tr>
    3736          <tr>
    37373692            <td class="reference"><b id="RFC3986">[RFC3986]</b></td>
    37383693            <td class="top"><a href="mailto:timbl@w3.org" title="World Wide Web Consortium">Berners-Lee, T.</a>, <a href="mailto:fielding@gbiv.com" title="Day Software">Fielding, R.</a>, and <a href="mailto:LMM@acm.org" title="Adobe Systems Incorporated">L. Masinter</a>, “<a href="http://tools.ietf.org/html/rfc3986">Uniform Resource Identifier (URI): Generic Syntax</a>”, STD&nbsp;66, RFC&nbsp;3986, January&nbsp;2005.
    … …  
    37553710         </tr>
    37563711      </table>
    3757       <h2 id="rfc.references.2"><a href="#rfc.section.13.2" id="rfc.section.13.2">13.2</a> Informative References
     3712      <h2 id="rfc.references.2"><a href="#rfc.section.14.2" id="rfc.section.14.2">14.2</a> Informative References
    37583713      </h2>
    37593714      <table>                                         
    … …  
    38933848         MIME environments.
    38943849      </p>
    3895       <div id="rfc.figure.u.63"></div><pre class="inline"><span id="rfc.iref.g.59"></span>  <a href="#mime-version" class="smpl">MIME-Version</a> = 1*<a href="#notation" class="smpl">DIGIT</a> "." 1*<a href="#notation" class="smpl">DIGIT</a>
     3850      <div id="rfc.figure.u.62"></div><pre class="inline"><span id="rfc.iref.g.59"></span>  <a href="#mime-version" class="smpl">MIME-Version</a> = 1*<a href="#abnf.dependencies" class="smpl">DIGIT</a> "." 1*<a href="#abnf.dependencies" class="smpl">DIGIT</a>
    38963851</pre><p id="rfc.section.A.1.p.3">MIME version "1.0" is the default for use in HTTP/1.1. However, HTTP/1.1 message parsing and semantics are defined by this
    38973852         document and not the MIME specification.
    … …  
    39803935      <p id="rfc.section.C.p.16">Allow <a href="#header.referer" class="smpl">Referer</a> field value of "about:blank" as alternative to not specifying it. (<a href="#header.referer" id="rfc.xref.header.referer.3" title="Referer">Section&nbsp;9.15</a>)
    39813936      </p>
    3982       <p id="rfc.section.C.p.17">In the description of the <a href="#header.server" class="smpl">Server</a> header field, the <a href="p1-messaging.html#header.via" class="smpl">Via</a> field was described as a SHOULD. The requirement was and is stated correctly in the description of the Via header field in <a href="p1-messaging.html#header.via" title="Via">Section 6.2</a> of <a href="#Part1" id="rfc.xref.Part1.58"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. (<a href="#header.server" id="rfc.xref.header.server.4" title="Server">Section&nbsp;9.17</a>)
     3937      <p id="rfc.section.C.p.17">In the description of the <a href="#header.server" class="smpl">Server</a> header field, the <a href="p1-messaging.html#header.via" class="smpl">Via</a> field was described as a SHOULD. The requirement was and is stated correctly in the description of the Via header field in <a href="p1-messaging.html#header.via" title="Via">Section 6.2</a> of <a href="#Part1" id="rfc.xref.Part1.56"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. (<a href="#header.server" id="rfc.xref.header.server.4" title="Server">Section&nbsp;9.17</a>)
    39833938      </p>
    39843939      <p id="rfc.section.C.p.18">Clarify contexts that charset is used in. (<a href="#character.sets" title="Character Encodings (charset)">Section&nbsp;5.3</a>)
    … …  
    40043959      </p>
    40053960      <h1 id="rfc.section.D"><a href="#rfc.section.D">D.</a>&nbsp;<a id="collected.abnf" href="#collected.abnf">Collected ABNF</a></h1>
    4006       <div id="rfc.figure.u.64"></div> <pre class="inline"><a href="#header.accept" class="smpl">Accept</a> = [ ( "," / ( media-range [ accept-params ] ) ) *( OWS "," [
     3961      <div id="rfc.figure.u.63"></div> <pre class="inline"><a href="#header.accept" class="smpl">Accept</a> = [ ( "," / ( media-range [ accept-params ] ) ) *( OWS "," [
    40073962 OWS ( media-range [ accept-params ] ) ] ) ]
    40083963<a href="#header.accept-charset" class="smpl">Accept-Charset</a> = *( "," OWS ) ( ( charset / "*" ) [ OWS ";" OWS "q="
    … …  
    40163971<a href="#header.allow" class="smpl">Allow</a> = [ ( "," / method ) *( OWS "," [ OWS method ] ) ]
    40173972
    4018 <a href="#core.rules" class="smpl">BWS</a> = &lt;BWS, defined in [Part1], Section 3.2.1&gt;
     3973<a href="#abnf.dependencies" class="smpl">BWS</a> = &lt;BWS, defined in [Part1], Section 3.2.1&gt;
    40193974
    40203975<a href="#header.content-encoding" class="smpl">Content-Encoding</a> = *( "," OWS ) content-coding *( OWS "," [ OWS
    … …  
    40403995<a href="#header.max-forwards" class="smpl">Max-Forwards</a> = 1*DIGIT
    40413996
    4042 <a href="#core.rules" class="smpl">OWS</a> = &lt;OWS, defined in [Part1], Section 3.2.1&gt;
     3997<a href="#abnf.dependencies" class="smpl">OWS</a> = &lt;OWS, defined in [Part1], Section 3.2.1&gt;
    40433998
    4044 <a href="#core.rules" class="smpl">RWS</a> = &lt;RWS, defined in [Part1], Section 3.2.1&gt;
     3999<a href="#abnf.dependencies" class="smpl">RWS</a> = &lt;RWS, defined in [Part1], Section 3.2.1&gt;
    40454000<a href="#header.referer" class="smpl">Referer</a> = absolute-URI / partial-URI
    40464001<a href="#header.retry-after" class="smpl">Retry-After</a> = HTTP-date / delta-seconds
    … …  
    41194074<a href="#product.tokens" class="smpl">product-version</a> = token
    41204075
    4121 <a href="#core.rules" class="smpl">quoted-string</a> = &lt;quoted-string, defined in [Part1], Section 3.2.4&gt;
     4076<a href="#abnf.dependencies" class="smpl">quoted-string</a> = &lt;quoted-string, defined in [Part1], Section 3.2.4&gt;
    41224077<a href="#abnf.dependencies" class="smpl">qvalue</a> = &lt;qvalue, defined in [Part1], Section 4.3.1&gt;
    41234078
    … …  
    41294084
    41304085<a href="#preferred.date.format" class="smpl">time-of-day</a> = hour ":" minute ":" second
    4131 <a href="#core.rules" class="smpl">token</a> = &lt;token, defined in [Part1], Section 3.2.4&gt;
     4086<a href="#abnf.dependencies" class="smpl">token</a> = &lt;token, defined in [Part1], Section 3.2.4&gt;
    41324087<a href="#media.types" class="smpl">type</a> = token
    41334088
    41344089<a href="#rule.parameter" class="smpl">value</a> = word
    41354090
    4136 <a href="#core.rules" class="smpl">word</a> = &lt;word, defined in [Part1], Section 3.2.4&gt;
     4091<a href="#abnf.dependencies" class="smpl">word</a> = &lt;word, defined in [Part1], Section 3.2.4&gt;
    41374092
    41384093<a href="#preferred.date.format" class="smpl">year</a> = 4DIGIT
    … …  
    47074662         <ul class="ind">
    47084663            <li><a id="rfc.index.1" href="#rfc.index.1"><b>1</b></a><ul>
    4709                   <li>100 Continue (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.100.1">4.1</a>, <a href="#rfc.iref.22"><b>4.3.1</b></a>, <a href="#rfc.xref.status.100.2">10.2</a></li>
     4664                  <li>100 Continue (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.100.1">4.1</a>, <a href="#rfc.iref.21"><b>4.3.1</b></a>, <a href="#rfc.xref.status.100.2">10.2</a></li>
    47104665                  <li>100-continue (expect value)&nbsp;&nbsp;<a href="#rfc.iref.139"><b>9.11</b></a></li>
    4711                   <li>101 Switching Protocols (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.101.1">4.1</a>, <a href="#rfc.iref.23"><b>4.3.2</b></a>, <a href="#rfc.xref.status.101.2">10.2</a></li>
    4712                   <li>1xx Informational (status code class)&nbsp;&nbsp;<a href="#rfc.iref.21"><b>4.3</b></a></li>
     4666                  <li>101 Switching Protocols (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.101.1">4.1</a>, <a href="#rfc.iref.22"><b>4.3.2</b></a>, <a href="#rfc.xref.status.101.2">10.2</a></li>
     4667                  <li>1xx Informational (status code class)&nbsp;&nbsp;<a href="#rfc.iref.20"><b>4.3</b></a></li>
    47134668               </ul>
    47144669            </li>
    47154670            <li><a id="rfc.index.2" href="#rfc.index.2"><b>2</b></a><ul>
    4716                   <li>200 OK (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.200.1">4.1</a>, <a href="#rfc.iref.25"><b>4.4.1</b></a>, <a href="#rfc.xref.status.200.2">10.2</a></li>
    4717                   <li>201 Created (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.201.1">4.1</a>, <a href="#rfc.iref.26"><b>4.4.2</b></a>, <a href="#rfc.xref.status.201.2">10.2</a></li>
    4718                   <li>202 Accepted (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.202.1">4.1</a>, <a href="#rfc.iref.27"><b>4.4.3</b></a>, <a href="#rfc.xref.status.202.2">10.2</a></li>
    4719                   <li>203 Non-Authoritative Information (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.203.1">4.1</a>, <a href="#rfc.iref.28"><b>4.4.4</b></a>, <a href="#rfc.xref.status.203.2">10.2</a>, <a href="#rfc.xref.status.203.3">C</a></li>
    4720                   <li>204 No Content (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.204.1">4.1</a>, <a href="#rfc.iref.29"><b>4.4.5</b></a>, <a href="#rfc.xref.status.204.2">10.2</a></li>
    4721                   <li>205 Reset Content (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.205.1">4.1</a>, <a href="#rfc.iref.30"><b>4.4.6</b></a>, <a href="#rfc.xref.status.205.2">10.2</a></li>
    4722                   <li>2xx Successful (status code class)&nbsp;&nbsp;<a href="#rfc.iref.24"><b>4.4</b></a></li>
     4671                  <li>200 OK (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.200.1">4.1</a>, <a href="#rfc.iref.24"><b>4.4.1</b></a>, <a href="#rfc.xref.status.200.2">10.2</a></li>
     4672                  <li>201 Created (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.201.1">4.1</a>, <a href="#rfc.iref.25"><b>4.4.2</b></a>, <a href="#rfc.xref.status.201.2">10.2</a></li>
     4673                  <li>202 Accepted (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.202.1">4.1</a>, <a href="#rfc.iref.26"><b>4.4.3</b></a>, <a href="#rfc.xref.status.202.2">10.2</a></li>
     4674                  <li>203 Non-Authoritative Information (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.203.1">4.1</a>, <a href="#rfc.iref.27"><b>4.4.4</b></a>, <a href="#rfc.xref.status.203.2">10.2</a>, <a href="#rfc.xref.status.203.3">C</a></li>
     4675                  <li>204 No Content (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.204.1">4.1</a>, <a href="#rfc.iref.28"><b>4.4.5</b></a>, <a href="#rfc.xref.status.204.2">10.2</a></li>
     4676                  <li>205 Reset Content (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.205.1">4.1</a>, <a href="#rfc.iref.29"><b>4.4.6</b></a>, <a href="#rfc.xref.status.205.2">10.2</a></li>
     4677                  <li>2xx Successful (status code class)&nbsp;&nbsp;<a href="#rfc.iref.23"><b>4.4</b></a></li>
    47234678               </ul>
    47244679            </li>
    47254680            <li><a id="rfc.index.3" href="#rfc.index.3"><b>3</b></a><ul>
    4726                   <li>300 Multiple Choices (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.300.1">4.1</a>, <a href="#rfc.iref.32"><b>4.5.1</b></a>, <a href="#rfc.xref.status.300.2">10.2</a></li>
    4727                   <li>301 Moved Permanently (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.301.1">4.1</a>, <a href="#rfc.iref.33"><b>4.5.2</b></a>, <a href="#rfc.xref.status.301.2">10.2</a>, <a href="#rfc.xref.status.301.3">C</a></li>
    4728                   <li>302 Found (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.302.1">4.1</a>, <a href="#rfc.iref.34"><b>4.5.3</b></a>, <a href="#rfc.xref.status.302.2">10.2</a>, <a href="#rfc.xref.status.302.3">C</a></li>
    4729                   <li>303 See Other (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.303.1">4.1</a>, <a href="#rfc.iref.35"><b>4.5.4</b></a>, <a href="#rfc.xref.status.303.2">10.2</a></li>
    4730                   <li>305 Use Proxy (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.305.1">4.1</a>, <a href="#rfc.iref.36"><b>4.5.5</b></a>, <a href="#rfc.xref.status.305.2">10.2</a>, <a href="#rfc.xref.status.305.3">C</a></li>
    4731                   <li>306 (Unused) (status code)&nbsp;&nbsp;<a href="#rfc.iref.37"><b>4.5.6</b></a>, <a href="#rfc.xref.status.306.1">10.2</a></li>
    4732                   <li>307 Temporary Redirect (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.307.1">4.1</a>, <a href="#rfc.iref.38"><b>4.5.7</b></a>, <a href="#rfc.xref.status.307.2">10.2</a>, <a href="#rfc.xref.status.307.3">C</a></li>
    4733                   <li>3xx Redirection (status code class)&nbsp;&nbsp;<a href="#rfc.iref.31"><b>4.5</b></a>, <a href="#rfc.xref.status.3xx.1">C</a></li>
     4681                  <li>300 Multiple Choices (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.300.1">4.1</a>, <a href="#rfc.iref.31"><b>4.5.1</b></a>, <a href="#rfc.xref.status.300.2">10.2</a></li>
     4682                  <li>301 Moved Permanently (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.301.1">4.1</a>, <a href="#rfc.iref.32"><b>4.5.2</b></a>, <a href="#rfc.xref.status.301.2">10.2</a>, <a href="#rfc.xref.status.301.3">C</a></li>
     4683                  <li>302 Found (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.302.1">4.1</a>, <a href="#rfc.iref.33"><b>4.5.3</b></a>, <a href="#rfc.xref.status.302.2">10.2</a>, <a href="#rfc.xref.status.302.3">C</a></li>
     4684                  <li>303 See Other (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.303.1">4.1</a>, <a href="#rfc.iref.34"><b>4.5.4</b></a>, <a href="#rfc.xref.status.303.2">10.2</a></li>
     4685                  <li>305 Use Proxy (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.305.1">4.1</a>, <a href="#rfc.iref.35"><b>4.5.5</b></a>, <a href="#rfc.xref.status.305.2">10.2</a>, <a href="#rfc.xref.status.305.3">C</a></li>
     4686                  <li>306 (Unused) (status code)&nbsp;&nbsp;<a href="#rfc.iref.36"><b>4.5.6</b></a>, <a href="#rfc.xref.status.306.1">10.2</a></li>
     4687                  <li>307 Temporary Redirect (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.307.1">4.1</a>, <a href="#rfc.iref.37"><b>4.5.7</b></a>, <a href="#rfc.xref.status.307.2">10.2</a>, <a href="#rfc.xref.status.307.3">C</a></li>
     4688                  <li>3xx Redirection (status code class)&nbsp;&nbsp;<a href="#rfc.iref.30"><b>4.5</b></a>, <a href="#rfc.xref.status.3xx.1">C</a></li>
    47344689               </ul>
    47354690            </li>
    47364691            <li><a id="rfc.index.4" href="#rfc.index.4"><b>4</b></a><ul>
    4737                   <li>400 Bad Request (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.400.1">4.1</a>, <a href="#rfc.iref.40"><b>4.6.1</b></a>, <a href="#rfc.xref.status.400.2">10.2</a></li>
    4738                   <li>402 Payment Required (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.402.1">4.1</a>, <a href="#rfc.iref.41"><b>4.6.2</b></a>, <a href="#rfc.xref.status.402.2">10.2</a></li>
    4739                   <li>403 Forbidden (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.403.1">4.1</a>, <a href="#rfc.iref.42"><b>4.6.3</b></a>, <a href="#rfc.xref.status.403.2">10.2</a></li>
    4740                   <li>404 Not Found (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.404.1">4.1</a>, <a href="#rfc.iref.43"><b>4.6.4</b></a>, <a href="#rfc.xref.status.404.2">10.2</a></li>
    4741                   <li>405 Method Not Allowed (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.405.1">4.1</a>, <a href="#rfc.iref.44"><b>4.6.5</b></a>, <a href="#rfc.xref.status.405.2">10.2</a></li>
    4742                   <li>406 Not Acceptable (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.406.1">4.1</a>, <a href="#rfc.iref.45"><b>4.6.6</b></a>, <a href="#rfc.xref.status.406.2">10.2</a></li>
    4743                   <li>408 Request Timeout (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.408.1">4.1</a>, <a href="#rfc.iref.46"><b>4.6.7</b></a>, <a href="#rfc.xref.status.408.2">10.2</a></li>
    4744                   <li>409 Conflict (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.409.1">4.1</a>, <a href="#rfc.iref.47"><b>4.6.8</b></a>, <a href="#rfc.xref.status.409.2">10.2</a></li>
    4745                   <li>410 Gone (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.410.1">4.1</a>, <a href="#rfc.iref.48"><b>4.6.9</b></a>, <a href="#rfc.xref.status.410.2">10.2</a></li>
    4746                   <li>411 Length Required (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.411.1">4.1</a>, <a href="#rfc.iref.49"><b>4.6.10</b></a>, <a href="#rfc.xref.status.411.2">10.2</a></li>
    4747                   <li>413 Request Representation Too Large (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.413.1">4.1</a>, <a href="#rfc.iref.50"><b>4.6.11</b></a>, <a href="#rfc.xref.status.413.2">10.2</a></li>
    4748                   <li>414 URI Too Long (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.414.1">4.1</a>, <a href="#rfc.iref.51"><b>4.6.12</b></a>, <a href="#rfc.xref.status.414.2">10.2</a></li>
    4749                   <li>415 Unsupported Media Type (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.415.1">4.1</a>, <a href="#rfc.iref.52"><b>4.6.13</b></a>, <a href="#rfc.xref.status.415.2">10.2</a></li>
    4750                   <li>417 Expectation Failed (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.417.1">4.1</a>, <a href="#rfc.iref.53"><b>4.6.14</b></a>, <a href="#rfc.xref.status.417.2">10.2</a></li>
    4751                   <li>426 Upgrade Required (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.426.1">4.1</a>, <a href="#rfc.iref.54"><b>4.6.15</b></a>, <a href="#rfc.xref.status.426.2">10.2</a>, <a href="#rfc.xref.status.426.3">C</a></li>
    4752                   <li>4xx Client Error (status code class)&nbsp;&nbsp;<a href="#rfc.iref.39"><b>4.6</b></a></li>
     4692                  <li>400 Bad Request (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.400.1">4.1</a>, <a href="#rfc.iref.39"><b>4.6.1</b></a>, <a href="#rfc.xref.status.400.2">10.2</a></li>
     4693                  <li>402 Payment Required (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.402.1">4.1</a>, <a href="#rfc.iref.40"><b>4.6.2</b></a>, <a href="#rfc.xref.status.402.2">10.2</a></li>
     4694                  <li>403 Forbidden (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.403.1">4.1</a>, <a href="#rfc.iref.41"><b>4.6.3</b></a>, <a href="#rfc.xref.status.403.2">10.2</a></li>
     4695                  <li>404 Not Found (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.404.1">4.1</a>, <a href="#rfc.iref.42"><b>4.6.4</b></a>, <a href="#rfc.xref.status.404.2">10.2</a></li>
     4696                  <li>405 Method Not Allowed (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.405.1">4.1</a>, <a href="#rfc.iref.43"><b>4.6.5</b></a>, <a href="#rfc.xref.status.405.2">10.2</a></li>
     4697                  <li>406 Not Acceptable (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.406.1">4.1</a>, <a href="#rfc.iref.44"><b>4.6.6</b></a>, <a href="#rfc.xref.status.406.2">10.2</a></li>
     4698                  <li>408 Request Timeout (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.408.1">4.1</a>, <a href="#rfc.iref.45"><b>4.6.7</b></a>, <a href="#rfc.xref.status.408.2">10.2</a></li>
     4699                  <li>409 Conflict (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.409.1">4.1</a>, <a href="#rfc.iref.46"><b>4.6.8</b></a>, <a href="#rfc.xref.status.409.2">10.2</a></li>
     4700                  <li>410 Gone (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.410.1">4.1</a>, <a href="#rfc.iref.47"><b>4.6.9</b></a>, <a href="#rfc.xref.status.410.2">10.2</a></li>
     4701                  <li>411 Length Required (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.411.1">4.1</a>, <a href="#rfc.iref.48"><b>4.6.10</b></a>, <a href="#rfc.xref.status.411.2">10.2</a></li>
     4702                  <li>413 Request Representation Too Large (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.413.1">4.1</a>, <a href="#rfc.iref.49"><b>4.6.11</b></a>, <a href="#rfc.xref.status.413.2">10.2</a></li>
     4703                  <li>414 URI Too Long (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.414.1">4.1</a>, <a href="#rfc.iref.50"><b>4.6.12</b></a>, <a href="#rfc.xref.status.414.2">10.2</a></li>
     4704                  <li>415 Unsupported Media Type (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.415.1">4.1</a>, <a href="#rfc.iref.51"><b>4.6.13</b></a>, <a href="#rfc.xref.status.415.2">10.2</a></li>
     4705                  <li>417 Expectation Failed (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.417.1">4.1</a>, <a href="#rfc.iref.52"><b>4.6.14</b></a>, <a href="#rfc.xref.status.417.2">10.2</a></li>
     4706                  <li>426 Upgrade Required (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.426.1">4.1</a>, <a href="#rfc.iref.53"><b>4.6.15</b></a>, <a href="#rfc.xref.status.426.2">10.2</a>, <a href="#rfc.xref.status.426.3">C</a></li>
     4707                  <li>4xx Client Error (status code class)&nbsp;&nbsp;<a href="#rfc.iref.38"><b>4.6</b></a></li>
    47534708               </ul>
    47544709            </li>
    47554710            <li><a id="rfc.index.5" href="#rfc.index.5"><b>5</b></a><ul>
    4756                   <li>500 Internal Server Error (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.500.1">4.1</a>, <a href="#rfc.iref.56"><b>4.7.1</b></a>, <a href="#rfc.xref.status.500.2">10.2</a></li>
    4757                   <li>501 Not Implemented (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.501.1">4.1</a>, <a href="#rfc.iref.57"><b>4.7.2</b></a>, <a href="#rfc.xref.status.501.2">10.2</a></li>
    4758                   <li>502 Bad Gateway (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.502.1">4.1</a>, <a href="#rfc.iref.58"><b>4.7.3</b></a>, <a href="#rfc.xref.status.502.2">10.2</a></li>
    4759                   <li>503 Service Unavailable (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.503.1">4.1</a>, <a href="#rfc.iref.59"><b>4.7.4</b></a>, <a href="#rfc.xref.status.503.2">10.2</a></li>
    4760                   <li>504 Gateway Timeout (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.504.1">4.1</a>, <a href="#rfc.iref.60"><b>4.7.5</b></a>, <a href="#rfc.xref.status.504.2">10.2</a></li>
    4761                   <li>505 HTTP Version Not Supported (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.505.1">4.1</a>, <a href="#rfc.iref.61"><b>4.7.6</b></a>, <a href="#rfc.xref.status.505.2">10.2</a></li>
    4762                   <li>5xx Server Error (status code class)&nbsp;&nbsp;<a href="#rfc.iref.55"><b>4.7</b></a></li>
     4711                  <li>500 Internal Server Error (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.500.1">4.1</a>, <a href="#rfc.iref.55"><b>4.7.1</b></a>, <a href="#rfc.xref.status.500.2">10.2</a></li>
     4712                  <li>501 Not Implemented (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.501.1">4.1</a>, <a href="#rfc.iref.56"><b>4.7.2</b></a>, <a href="#rfc.xref.status.501.2">10.2</a></li>
     4713                  <li>502 Bad Gateway (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.502.1">4.1</a>, <a href="#rfc.iref.57"><b>4.7.3</b></a>, <a href="#rfc.xref.status.502.2">10.2</a></li>
     4714                  <li>503 Service Unavailable (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.503.1">4.1</a>, <a href="#rfc.iref.58"><b>4.7.4</b></a>, <a href="#rfc.xref.status.503.2">10.2</a></li>
     4715                  <li>504 Gateway Timeout (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.504.1">4.1</a>, <a href="#rfc.iref.59"><b>4.7.5</b></a>, <a href="#rfc.xref.status.504.2">10.2</a></li>
     4716                  <li>505 HTTP Version Not Supported (status code)&nbsp;&nbsp;<a href="#rfc.xref.status.505.1">4.1</a>, <a href="#rfc.iref.60"><b>4.7.6</b></a>, <a href="#rfc.xref.status.505.2">10.2</a></li>
     4717                  <li>5xx Server Error (status code class)&nbsp;&nbsp;<a href="#rfc.iref.54"><b>4.7</b></a></li>
    47634718               </ul>
    47644719            </li>
    … …  
    47814736                  <li>compress (Coding Format)&nbsp;&nbsp;<a href="#rfc.iref.c.3">5.4</a></li>
    47824737                  <li>CONNECT method&nbsp;&nbsp;<a href="#rfc.iref.c.2"><b>2.3.8</b></a>, <a href="#rfc.xref.CONNECT.1">10.1</a>, <a href="#rfc.xref.CONNECT.2">C</a></li>
    4783                   <li>content negotiation&nbsp;&nbsp;<a href="#rfc.iref.c.1">1.1</a></li>
     4738                  <li>content negotiation&nbsp;&nbsp;<a href="#rfc.iref.c.1">1</a></li>
    47844739                  <li>Content-Encoding header field&nbsp;&nbsp;<a href="#rfc.xref.header.content-encoding.1">5.4</a>, <a href="#rfc.xref.header.content-encoding.2">7.2</a>, <a href="#rfc.iref.c.7"><b>9.6</b></a>, <a href="#rfc.xref.header.content-encoding.3">9.6</a>, <a href="#rfc.xref.header.content-encoding.4">10.3</a></li>
    47854740                  <li>Content-Language header field&nbsp;&nbsp;<a href="#rfc.xref.header.content-language.1">7.2</a>, <a href="#rfc.iref.c.8"><b>9.7</b></a>, <a href="#rfc.xref.header.content-language.2">10.3</a></li>
    … …  
    47934748                  <li>deflate (Coding Format)&nbsp;&nbsp;<a href="#rfc.iref.d.2">5.4</a></li>
    47944749                  <li>DELETE method&nbsp;&nbsp;<a href="#rfc.iref.d.1"><b>2.3.6</b></a>, <a href="#rfc.xref.DELETE.1">10.1</a></li>
    4795                   <li><em>draft-reschke-http-status-308</em>&nbsp;&nbsp;<a href="#rfc.xref.draft-reschke-http-status-308.1">4.5.7</a>, <a href="#draft-reschke-http-status-308"><b>13.2</b></a></li>
     4750                  <li><em>draft-reschke-http-status-308</em>&nbsp;&nbsp;<a href="#rfc.xref.draft-reschke-http-status-308.1">4.5.7</a>, <a href="#draft-reschke-http-status-308"><b>14.2</b></a></li>
    47964751               </ul>
    47974752            </li>
    … …  
    48974852                        <li>Referer&nbsp;&nbsp;<a href="#rfc.xref.header.referer.1">3.2</a>, <a href="#rfc.iref.h.16"><b>9.15</b></a>, <a href="#rfc.xref.header.referer.2">10.3</a>, <a href="#rfc.xref.header.referer.3">C</a></li>
    48984853                        <li>Retry-After&nbsp;&nbsp;<a href="#rfc.xref.header.retry-after.1">3.3</a>, <a href="#rfc.xref.header.retry-after.2">4.7.4</a>, <a href="#rfc.iref.h.17"><b>9.16</b></a>, <a href="#rfc.xref.header.retry-after.3">10.3</a></li>
    4899                         <li>Server&nbsp;&nbsp;<a href="#rfc.xref.header.server.1">3.3</a>, <a href="#rfc.iref.h.18"><b>9.17</b></a>, <a href="#rfc.xref.header.server.2">10.3</a>, <a href="#rfc.xref.header.server.3">11.1</a>, <a href="#rfc.xref.header.server.4">C</a></li>
    4900                         <li>User-Agent&nbsp;&nbsp;<a href="#rfc.xref.header.user-agent.1">3.2</a>, <a href="#rfc.xref.header.user-agent.2">8.1</a>, <a href="#rfc.iref.h.19"><b>9.18</b></a>, <a href="#rfc.xref.header.user-agent.3">10.3</a>, <a href="#rfc.xref.header.user-agent.4">11.1</a></li>
     4854                        <li>Server&nbsp;&nbsp;<a href="#rfc.xref.header.server.1">3.3</a>, <a href="#rfc.iref.h.18"><b>9.17</b></a>, <a href="#rfc.xref.header.server.2">10.3</a>, <a href="#rfc.xref.header.server.3">12.1</a>, <a href="#rfc.xref.header.server.4">C</a></li>
     4855                        <li>User-Agent&nbsp;&nbsp;<a href="#rfc.xref.header.user-agent.1">3.2</a>, <a href="#rfc.xref.header.user-agent.2">8.1</a>, <a href="#rfc.iref.h.19"><b>9.18</b></a>, <a href="#rfc.xref.header.user-agent.3">10.3</a>, <a href="#rfc.xref.header.user-agent.4">12.1</a></li>
    49014856                     </ul>
    49024857                  </li>
    … …  
    49224877                        <li>POST&nbsp;&nbsp;<a href="#rfc.iref.m.4"><b>2.3.4</b></a>, <a href="#rfc.xref.POST.1">10.1</a>, <a href="#rfc.xref.POST.2">C</a></li>
    49234878                        <li>PUT&nbsp;&nbsp;<a href="#rfc.iref.m.5"><b>2.3.5</b></a>, <a href="#rfc.xref.PUT.1">10.1</a>, <a href="#rfc.xref.PUT.2">C</a></li>
    4924                         <li>TRACE&nbsp;&nbsp;<a href="#rfc.iref.m.7"><b>2.3.7</b></a>, <a href="#rfc.xref.TRACE.1">9.14</a>, <a href="#rfc.xref.TRACE.2">10.1</a>, <a href="#rfc.xref.TRACE.3">11.1</a></li>
     4879                        <li>TRACE&nbsp;&nbsp;<a href="#rfc.iref.m.7"><b>2.3.7</b></a>, <a href="#rfc.xref.TRACE.1">9.14</a>, <a href="#rfc.xref.TRACE.2">10.1</a>, <a href="#rfc.xref.TRACE.3">12.1</a></li>
    49254880                     </ul>
    49264881                  </li>
    … …  
    49334888            </li>
    49344889            <li><a id="rfc.index.P" href="#rfc.index.P"><b>P</b></a><ul>
    4935                   <li><em>Part1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.1">1</a>, <a href="#rfc.xref.Part1.2">1.2</a>, <a href="#rfc.xref.Part1.3">1.3</a>, <a href="#rfc.xref.Part1.4">1.3.1</a>, <a href="#rfc.xref.Part1.5">1.3.1</a>, <a href="#rfc.xref.Part1.6">1.3.1</a>, <a href="#rfc.xref.Part1.7">1.3.1</a>, <a href="#rfc.xref.Part1.8">1.3.1</a>, <a href="#rfc.xref.Part1.9">1.3.1</a>, <a href="#rfc.xref.Part1.10">1.3.1</a>, <a href="#rfc.xref.Part1.11">1.3.2</a>, <a href="#rfc.xref.Part1.12">1.3.2</a>, <a href="#rfc.xref.Part1.13">1.3.2</a>, <a href="#rfc.xref.Part1.14">1.3.2</a>, <a href="#rfc.xref.Part1.15">1.3.2</a>, <a href="#rfc.xref.Part1.16">2</a>, <a href="#rfc.xref.Part1.17">2.2.1</a>, <a href="#rfc.xref.Part1.18">2.3.1</a>, <a href="#rfc.xref.Part1.19">2.3.7</a>, <a href="#rfc.xref.Part1.20">2.3.7</a>, <a href="#rfc.xref.Part1.21">2.3.8</a>, <a href="#rfc.xref.Part1.22">3</a>, <a href="#rfc.xref.Part1.23">3.1</a>, <a href="#rfc.xref.Part1.24">3.1</a>, <a href="#rfc.xref.Part1.25">3.1</a>, <a href="#rfc.xref.Part1.26">3.1</a>, <a href="#rfc.xref.Part1.27">3.1</a>, <a href="#rfc.xref.Part1.28">3.2</a>, <a href="#rfc.xref.Part1.29">3.2</a>, <a href="#rfc.xref.Part1.30">3.3</a>, <a href="#rfc.xref.Part1.31">4.3.1</a>, <a href="#rfc.xref.Part1.32">4.3.2</a>, <a href="#rfc.xref.Part1.33">4.4.4</a>, <a href="#rfc.xref.Part1.34">4.4.6</a>, <a href="#rfc.xref.Part1.35">4.6.15</a>, <a href="#rfc.xref.Part1.36">4.7.6</a>, <a href="#rfc.xref.Part1.37">5.4</a>, <a href="#rfc.xref.Part1.38">5.4</a>, <a href="#rfc.xref.Part1.39">5.4</a>, <a href="#rfc.xref.Part1.40">5.4.1</a>, <a href="#rfc.xref.Part1.41">5.4.1</a>, <a href="#rfc.xref.Part1.42">6.1</a>, <a href="#rfc.xref.Part1.43">6.2</a>, <a href="#rfc.xref.Part1.44">7</a>, <a href="#rfc.xref.Part1.45">7.1</a>, <a href="#rfc.xref.Part1.46">8.1</a>, <a href="#rfc.xref.Part1.47">9.1</a>, <a href="#rfc.xref.Part1.48">9.3</a>, <a href="#rfc.xref.Part1.49">9.8</a>, <a href="#rfc.xref.Part1.50">9.11</a>, <a href="#rfc.xref.Part1.51">9.17</a>, <a href="#rfc.xref.Part1.52">9.17</a>, <a href="#rfc.xref.Part1.53">9.18</a>, <a href="#rfc.xref.Part1.54">10.4</a>, <a href="#rfc.xref.Part1.55">10.4</a>, <a href="#rfc.xref.Part1.56">10.4</a>, <a href="#rfc.xref.Part1.57">12</a>, <a href="#Part1"><b>13.1</b></a>, <a href="#rfc.xref.Part1.58">C</a><ul>
    4936                         <li><em>Section 1.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.3">1.3</a></li>
    4937                         <li><em>Section 2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.2">1.2</a></li>
    4938                         <li><em>Section 2.4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.33">4.4.4</a></li>
    4939                         <li><em>Section 2.7</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.36">4.7.6</a></li>
    4940                         <li><em>Section 2.8</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.11">1.3.2</a>, <a href="#rfc.xref.Part1.13">1.3.2</a>, <a href="#rfc.xref.Part1.15">1.3.2</a></li>
    4941                         <li><em>Section 3.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.5">1.3.1</a>, <a href="#rfc.xref.Part1.6">1.3.1</a>, <a href="#rfc.xref.Part1.7">1.3.1</a></li>
    4942                         <li><em>Section 3.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.22">3</a>, <a href="#rfc.xref.Part1.25">3.1</a>, <a href="#rfc.xref.Part1.51">9.17</a>, <a href="#rfc.xref.Part1.53">9.18</a></li>
    4943                         <li><em>Section 3.2.4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.8">1.3.1</a>, <a href="#rfc.xref.Part1.9">1.3.1</a>, <a href="#rfc.xref.Part1.10">1.3.1</a>, <a href="#rfc.xref.Part1.12">1.3.2</a>, <a href="#rfc.xref.Part1.24">3.1</a></li>
    4944                         <li><em>Section 3.2.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.23">3.1</a></li>
    4945                         <li><em>Section 3.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.17">2.2.1</a>, <a href="#rfc.xref.Part1.34">4.4.6</a>, <a href="#rfc.xref.Part1.43">6.2</a>, <a href="#rfc.xref.Part1.44">7</a></li>
    4946                         <li><em>Section 3.3.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.42">6.1</a></li>
    4947                         <li><em>Section 4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.40">5.4.1</a></li>
    4948                         <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.27">3.1</a></li>
    4949                         <li><em>Section 4.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.37">5.4</a>, <a href="#rfc.xref.Part1.54">10.4</a></li>
    4950                         <li><em>Section 4.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.41">5.4.1</a></li>
    4951                         <li><em>Section 4.2.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.38">5.4</a>, <a href="#rfc.xref.Part1.55">10.4</a></li>
    4952                         <li><em>Section 4.2.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.39">5.4</a>, <a href="#rfc.xref.Part1.56">10.4</a></li>
    4953                         <li><em>Section 4.3.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.14">1.3.2</a>, <a href="#rfc.xref.Part1.46">8.1</a>, <a href="#rfc.xref.Part1.47">9.1</a>, <a href="#rfc.xref.Part1.48">9.3</a></li>
    4954                         <li><em>Section 4.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.29">3.2</a></li>
    4955                         <li><em>Section 5.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.18">2.3.1</a>, <a href="#rfc.xref.Part1.21">2.3.8</a></li>
    4956                         <li><em>Section 5.4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.28">3.2</a></li>
    4957                         <li><em>Section 5.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.16">2</a>, <a href="#rfc.xref.Part1.30">3.3</a>, <a href="#rfc.xref.Part1.45">7.1</a>, <a href="#rfc.xref.Part1.49">9.8</a></li>
    4958                         <li><em>Section 6.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.26">3.1</a></li>
    4959                         <li><em>Section 6.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.19">2.3.7</a>, <a href="#rfc.xref.Part1.52">9.17</a>, <a href="#rfc.xref.Part1.58">C</a></li>
    4960                         <li><em>Section 6.4.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.31">4.3.1</a>, <a href="#rfc.xref.Part1.50">9.11</a></li>
    4961                         <li><em>Section 6.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.32">4.3.2</a>, <a href="#rfc.xref.Part1.35">4.6.15</a></li>
    4962                         <li><em>Section 7.3.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.20">2.3.7</a></li>
    4963                         <li><em>Section 9</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.57">12</a></li>
     4890                  <li><em>Part1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.1">1</a>, <a href="#rfc.xref.Part1.2">2</a>, <a href="#rfc.xref.Part1.3">2.2.1</a>, <a href="#rfc.xref.Part1.4">2.3.1</a>, <a href="#rfc.xref.Part1.5">2.3.7</a>, <a href="#rfc.xref.Part1.6">2.3.7</a>, <a href="#rfc.xref.Part1.7">2.3.8</a>, <a href="#rfc.xref.Part1.8">3</a>, <a href="#rfc.xref.Part1.9">3.1</a>, <a href="#rfc.xref.Part1.10">3.1</a>, <a href="#rfc.xref.Part1.11">3.1</a>, <a href="#rfc.xref.Part1.12">3.1</a>, <a href="#rfc.xref.Part1.13">3.1</a>, <a href="#rfc.xref.Part1.14">3.2</a>, <a href="#rfc.xref.Part1.15">3.2</a>, <a href="#rfc.xref.Part1.16">3.3</a>, <a href="#rfc.xref.Part1.17">4.3.1</a>, <a href="#rfc.xref.Part1.18">4.3.2</a>, <a href="#rfc.xref.Part1.19">4.4.4</a>, <a href="#rfc.xref.Part1.20">4.4.6</a>, <a href="#rfc.xref.Part1.21">4.6.15</a>, <a href="#rfc.xref.Part1.22">4.7.6</a>, <a href="#rfc.xref.Part1.23">5.4</a>, <a href="#rfc.xref.Part1.24">5.4</a>, <a href="#rfc.xref.Part1.25">5.4</a>, <a href="#rfc.xref.Part1.26">5.4.1</a>, <a href="#rfc.xref.Part1.27">5.4.1</a>, <a href="#rfc.xref.Part1.28">6.1</a>, <a href="#rfc.xref.Part1.29">6.2</a>, <a href="#rfc.xref.Part1.30">7</a>, <a href="#rfc.xref.Part1.31">7.1</a>, <a href="#rfc.xref.Part1.32">8.1</a>, <a href="#rfc.xref.Part1.33">9.1</a>, <a href="#rfc.xref.Part1.34">9.3</a>, <a href="#rfc.xref.Part1.35">9.8</a>, <a href="#rfc.xref.Part1.36">9.11</a>, <a href="#rfc.xref.Part1.37">9.17</a>, <a href="#rfc.xref.Part1.38">9.17</a>, <a href="#rfc.xref.Part1.39">9.18</a>, <a href="#rfc.xref.Part1.40">10.4</a>, <a href="#rfc.xref.Part1.41">10.4</a>, <a href="#rfc.xref.Part1.42">10.4</a>, <a href="#rfc.xref.Part1.43">11</a>, <a href="#rfc.xref.Part1.44">11</a>, <a href="#rfc.xref.Part1.45">11</a>, <a href="#rfc.xref.Part1.46">11</a>, <a href="#rfc.xref.Part1.47">11</a>, <a href="#rfc.xref.Part1.48">11</a>, <a href="#rfc.xref.Part1.49">11</a>, <a href="#rfc.xref.Part1.50">11</a>, <a href="#rfc.xref.Part1.51">11</a>, <a href="#rfc.xref.Part1.52">11</a>, <a href="#rfc.xref.Part1.53">11</a>, <a href="#rfc.xref.Part1.54">11</a>, <a href="#rfc.xref.Part1.55">13</a>, <a href="#Part1"><b>14.1</b></a>, <a href="#rfc.xref.Part1.56">C</a><ul>
     4891                        <li><em>Section 1.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.43">11</a></li>
     4892                        <li><em>Section 2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.1">1</a></li>
     4893                        <li><em>Section 2.4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.19">4.4.4</a></li>
     4894                        <li><em>Section 2.7</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.22">4.7.6</a></li>
     4895                        <li><em>Section 2.8</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.47">11</a>, <a href="#rfc.xref.Part1.48">11</a>, <a href="#rfc.xref.Part1.49">11</a></li>
     4896                        <li><em>Section 3.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.8">3</a>, <a href="#rfc.xref.Part1.11">3.1</a>, <a href="#rfc.xref.Part1.37">9.17</a>, <a href="#rfc.xref.Part1.39">9.18</a></li>
     4897                        <li><em>Section 3.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.44">11</a>, <a href="#rfc.xref.Part1.45">11</a>, <a href="#rfc.xref.Part1.46">11</a></li>
     4898                        <li><em>Section 3.2.4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.10">3.1</a>, <a href="#rfc.xref.Part1.50">11</a>, <a href="#rfc.xref.Part1.52">11</a>, <a href="#rfc.xref.Part1.53">11</a>, <a href="#rfc.xref.Part1.54">11</a></li>
     4899                        <li><em>Section 3.2.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.9">3.1</a></li>
     4900                        <li><em>Section 3.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.3">2.2.1</a>, <a href="#rfc.xref.Part1.20">4.4.6</a>, <a href="#rfc.xref.Part1.29">6.2</a>, <a href="#rfc.xref.Part1.30">7</a></li>
     4901                        <li><em>Section 3.3.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.28">6.1</a></li>
     4902                        <li><em>Section 4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.26">5.4.1</a></li>
     4903                        <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.13">3.1</a></li>
     4904                        <li><em>Section 4.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.23">5.4</a>, <a href="#rfc.xref.Part1.40">10.4</a></li>
     4905                        <li><em>Section 4.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.27">5.4.1</a></li>
     4906                        <li><em>Section 4.2.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.24">5.4</a>, <a href="#rfc.xref.Part1.41">10.4</a></li>
     4907                        <li><em>Section 4.2.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.25">5.4</a>, <a href="#rfc.xref.Part1.42">10.4</a></li>
     4908                        <li><em>Section 4.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.15">3.2</a></li>
     4909                        <li><em>Section 4.3.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.32">8.1</a>, <a href="#rfc.xref.Part1.33">9.1</a>, <a href="#rfc.xref.Part1.34">9.3</a>, <a href="#rfc.xref.Part1.51">11</a></li>
     4910                        <li><em>Section 5.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.4">2.3.1</a>, <a href="#rfc.xref.Part1.7">2.3.8</a></li>
     4911                        <li><em>Section 5.4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.14">3.2</a></li>
     4912                        <li><em>Section 5.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.2">2</a>, <a href="#rfc.xref.Part1.16">3.3</a>, <a href="#rfc.xref.Part1.31">7.1</a>, <a href="#rfc.xref.Part1.35">9.8</a></li>
     4913                        <li><em>Section 6.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.12">3.1</a></li>
     4914                        <li><em>Section 6.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.5">2.3.7</a>, <a href="#rfc.xref.Part1.38">9.17</a>, <a href="#rfc.xref.Part1.56">C</a></li>
     4915                        <li><em>Section 6.4.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.17">4.3.1</a>, <a href="#rfc.xref.Part1.36">9.11</a></li>
     4916                        <li><em>Section 6.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.18">4.3.2</a>, <a href="#rfc.xref.Part1.21">4.6.15</a></li>
     4917                        <li><em>Section 7.3.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.6">2.3.7</a></li>
     4918                        <li><em>Section 9</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.55">13</a></li>
    49644919                     </ul>
    49654920                  </li>
    4966                   <li><em>Part4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part4.1">2.3.2</a>, <a href="#rfc.xref.Part4.2">3.2</a>, <a href="#rfc.xref.Part4.3">3.2</a>, <a href="#rfc.xref.Part4.4">3.2</a>, <a href="#rfc.xref.Part4.5">3.2</a>, <a href="#rfc.xref.Part4.6">3.3</a>, <a href="#rfc.xref.Part4.7">4.1</a>, <a href="#rfc.xref.Part4.8">4.1</a>, <a href="#rfc.xref.Part4.9">4.1</a>, <a href="#rfc.xref.Part4.10">4.4.2</a>, <a href="#rfc.xref.Part4.11">4.5</a>, <a href="#rfc.xref.Part4.12">7.2</a>, <a href="#rfc.xref.Part4.13">7.2</a>, <a href="#Part4"><b>13.1</b></a>, <a href="#rfc.xref.Part4.14">E.2</a><ul>
     4921                  <li><em>Part4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part4.1">2.3.2</a>, <a href="#rfc.xref.Part4.2">3.2</a>, <a href="#rfc.xref.Part4.3">3.2</a>, <a href="#rfc.xref.Part4.4">3.2</a>, <a href="#rfc.xref.Part4.5">3.2</a>, <a href="#rfc.xref.Part4.6">3.3</a>, <a href="#rfc.xref.Part4.7">4.1</a>, <a href="#rfc.xref.Part4.8">4.1</a>, <a href="#rfc.xref.Part4.9">4.1</a>, <a href="#rfc.xref.Part4.10">4.4.2</a>, <a href="#rfc.xref.Part4.11">4.5</a>, <a href="#rfc.xref.Part4.12">7.2</a>, <a href="#rfc.xref.Part4.13">7.2</a>, <a href="#Part4"><b>14.1</b></a>, <a href="#rfc.xref.Part4.14">E.2</a><ul>
    49674922                        <li><em>Section 2.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part4.13">7.2</a></li>
    49684923                        <li><em>Section 2.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part4.6">3.3</a>, <a href="#rfc.xref.Part4.10">4.4.2</a>, <a href="#rfc.xref.Part4.12">7.2</a></li>
    … …  
    49764931                     </ul>
    49774932                  </li>
    4978                   <li><em>Part5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part5.1">2.3.2</a>, <a href="#rfc.xref.Part5.2">2.3.2</a>, <a href="#rfc.xref.Part5.3">2.3.5</a>, <a href="#rfc.xref.Part5.4">3.2</a>, <a href="#rfc.xref.Part5.5">3.2</a>, <a href="#rfc.xref.Part5.6">3.3</a>, <a href="#rfc.xref.Part5.7">4.1</a>, <a href="#rfc.xref.Part5.8">4.1</a>, <a href="#rfc.xref.Part5.9">4.1</a>, <a href="#rfc.xref.Part5.10">6.1</a>, <a href="#Part5"><b>13.1</b></a><ul>
     4933                  <li><em>Part5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part5.1">2.3.2</a>, <a href="#rfc.xref.Part5.2">2.3.2</a>, <a href="#rfc.xref.Part5.3">2.3.5</a>, <a href="#rfc.xref.Part5.4">3.2</a>, <a href="#rfc.xref.Part5.5">3.2</a>, <a href="#rfc.xref.Part5.6">3.3</a>, <a href="#rfc.xref.Part5.7">4.1</a>, <a href="#rfc.xref.Part5.8">4.1</a>, <a href="#rfc.xref.Part5.9">4.1</a>, <a href="#rfc.xref.Part5.10">6.1</a>, <a href="#Part5"><b>14.1</b></a><ul>
    49794934                        <li><em>Section 3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part5.7">4.1</a></li>
    49804935                        <li><em>Section 3.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part5.8">4.1</a></li>
    … …  
    49864941                     </ul>
    49874942                  </li>
    4988                   <li><em>Part6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">2.2.1</a>, <a href="#rfc.xref.Part6.2">2.3.2</a>, <a href="#rfc.xref.Part6.3">2.3.3</a>, <a href="#rfc.xref.Part6.4">2.3.4</a>, <a href="#rfc.xref.Part6.5">2.3.5</a>, <a href="#rfc.xref.Part6.6">2.3.6</a>, <a href="#rfc.xref.Part6.7">3.1</a>, <a href="#rfc.xref.Part6.8">3.3</a>, <a href="#rfc.xref.Part6.9">3.3</a>, <a href="#rfc.xref.Part6.10">4.2.1</a>, <a href="#rfc.xref.Part6.11">4.4.1</a>, <a href="#rfc.xref.Part6.12">4.4.4</a>, <a href="#rfc.xref.Part6.13">4.4.4</a>, <a href="#rfc.xref.Part6.14">4.4.4</a>, <a href="#rfc.xref.Part6.15">4.5.1</a>, <a href="#rfc.xref.Part6.16">4.5.2</a>, <a href="#rfc.xref.Part6.17">4.6.9</a>, <a href="#rfc.xref.Part6.18">7.2</a>, <a href="#rfc.xref.Part6.19">8.1</a>, <a href="#Part6"><b>13.1</b></a><ul>
     4943                  <li><em>Part6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">2.2.1</a>, <a href="#rfc.xref.Part6.2">2.3.2</a>, <a href="#rfc.xref.Part6.3">2.3.3</a>, <a href="#rfc.xref.Part6.4">2.3.4</a>, <a href="#rfc.xref.Part6.5">2.3.5</a>, <a href="#rfc.xref.Part6.6">2.3.6</a>, <a href="#rfc.xref.Part6.7">3.1</a>, <a href="#rfc.xref.Part6.8">3.3</a>, <a href="#rfc.xref.Part6.9">3.3</a>, <a href="#rfc.xref.Part6.10">4.2.1</a>, <a href="#rfc.xref.Part6.11">4.4.1</a>, <a href="#rfc.xref.Part6.12">4.4.4</a>, <a href="#rfc.xref.Part6.13">4.4.4</a>, <a href="#rfc.xref.Part6.14">4.4.4</a>, <a href="#rfc.xref.Part6.15">4.5.1</a>, <a href="#rfc.xref.Part6.16">4.5.2</a>, <a href="#rfc.xref.Part6.17">4.6.9</a>, <a href="#rfc.xref.Part6.18">7.2</a>, <a href="#rfc.xref.Part6.19">8.1</a>, <a href="#Part6"><b>14.1</b></a><ul>
    49894944                        <li><em>Section 4.1.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.4">2.3.4</a></li>
    49904945                        <li><em>Section 4.1.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.11">4.4.1</a>, <a href="#rfc.xref.Part6.14">4.4.4</a>, <a href="#rfc.xref.Part6.15">4.5.1</a>, <a href="#rfc.xref.Part6.16">4.5.2</a>, <a href="#rfc.xref.Part6.17">4.6.9</a></li>
    … …  
    49984953                     </ul>
    49994954                  </li>
    5000                   <li><em>Part7</em>&nbsp;&nbsp;<a href="#rfc.xref.Part7.1">3.2</a>, <a href="#rfc.xref.Part7.2">3.2</a>, <a href="#rfc.xref.Part7.3">3.3</a>, <a href="#rfc.xref.Part7.4">3.3</a>, <a href="#rfc.xref.Part7.5">4.1</a>, <a href="#rfc.xref.Part7.6">4.1</a>, <a href="#rfc.xref.Part7.7">4.1</a>, <a href="#Part7"><b>13.1</b></a><ul>
     4955                  <li><em>Part7</em>&nbsp;&nbsp;<a href="#rfc.xref.Part7.1">3.2</a>, <a href="#rfc.xref.Part7.2">3.2</a>, <a href="#rfc.xref.Part7.3">3.3</a>, <a href="#rfc.xref.Part7.4">3.3</a>, <a href="#rfc.xref.Part7.5">4.1</a>, <a href="#rfc.xref.Part7.6">4.1</a>, <a href="#rfc.xref.Part7.7">4.1</a>, <a href="#Part7"><b>14.1</b></a><ul>
    50014956                        <li><em>Section 3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part7.5">4.1</a></li>
    50024957                        <li><em>Section 3.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part7.6">4.1</a></li>
    … …  
    50174972                  <li>representation&nbsp;&nbsp;<a href="#rfc.iref.r.1">7</a></li>
    50184973                  <li>Retry-After header field&nbsp;&nbsp;<a href="#rfc.xref.header.retry-after.1">3.3</a>, <a href="#rfc.xref.header.retry-after.2">4.7.4</a>, <a href="#rfc.iref.r.3"><b>9.16</b></a>, <a href="#rfc.xref.header.retry-after.3">10.3</a></li>
    5019                   <li><em>RFC1123</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1123.1">5.1</a>, <a href="#rfc.xref.RFC1123.2">5.1</a>, <a href="#RFC1123"><b>13.2</b></a><ul>
     4974                  <li><em>RFC1123</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1123.1">5.1</a>, <a href="#rfc.xref.RFC1123.2">5.1</a>, <a href="#RFC1123"><b>14.2</b></a><ul>
    50204975                        <li><em>Section 5.2.14</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1123.2">5.1</a></li>
    50214976                     </ul>
    50224977                  </li>
    5023                   <li><em>RFC1945</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1945.1">4.5</a>, <a href="#RFC1945"><b>13.2</b></a>, <a href="#rfc.xref.RFC1945.2">B</a><ul>
     4978                  <li><em>RFC1945</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1945.1">4.5</a>, <a href="#RFC1945"><b>14.2</b></a>, <a href="#rfc.xref.RFC1945.2">B</a><ul>
    50244979                        <li><em>Section 9.3</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1945.1">4.5</a></li>
    50254980                     </ul>
    50264981                  </li>
    5027                   <li><em>RFC1950</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1950.1">10.4</a>, <a href="#RFC1950"><b>13.1</b></a></li>
    5028                   <li><em>RFC1951</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1951.1">10.4</a>, <a href="#RFC1951"><b>13.1</b></a></li>
    5029                   <li><em>RFC1952</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1952.1">10.4</a>, <a href="#RFC1952"><b>13.1</b></a></li>
    5030                   <li><em>RFC2045</em>&nbsp;&nbsp;<a href="#RFC2045"><b>13.1</b></a>, <a href="#rfc.xref.RFC2045.1">A</a>, <a href="#rfc.xref.RFC2045.2">A.1</a></li>
    5031                   <li><em>RFC2046</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2046.1">5.5</a>, <a href="#rfc.xref.RFC2046.2">5.5.2</a>, <a href="#rfc.xref.RFC2046.3">7.3</a>, <a href="#RFC2046"><b>13.1</b></a>, <a href="#rfc.xref.RFC2046.4">A.2</a><ul>
     4982                  <li><em>RFC1950</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1950.1">10.4</a>, <a href="#RFC1950"><b>14.1</b></a></li>
     4983                  <li><em>RFC1951</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1951.1">10.4</a>, <a href="#RFC1951"><b>14.1</b></a></li>
     4984                  <li><em>RFC1952</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC1952.1">10.4</a>, <a href="#RFC1952"><b>14.1</b></a></li>
     4985                  <li><em>RFC2045</em>&nbsp;&nbsp;<a href="#RFC2045"><b>14.1</b></a>, <a href="#rfc.xref.RFC2045.1">A</a>, <a href="#rfc.xref.RFC2045.2">A.1</a></li>
     4986                  <li><em>RFC2046</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2046.1">5.5</a>, <a href="#rfc.xref.RFC2046.2">5.5.2</a>, <a href="#rfc.xref.RFC2046.3">7.3</a>, <a href="#RFC2046"><b>14.1</b></a>, <a href="#rfc.xref.RFC2046.4">A.2</a><ul>
    50324987                        <li><em>Section 4.5.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2046.3">7.3</a></li>
    50334988                        <li><em>Section 5.1.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2046.2">5.5.2</a></li>
    50344989                     </ul>
    50354990                  </li>
    5036                   <li><em>RFC2049</em>&nbsp;&nbsp;<a href="#RFC2049"><b>13.2</b></a>, <a href="#rfc.xref.RFC2049.1">A.2</a><ul>
     4991                  <li><em>RFC2049</em>&nbsp;&nbsp;<a href="#RFC2049"><b>14.2</b></a>, <a href="#rfc.xref.RFC2049.1">A.2</a><ul>
    50374992                        <li><em>Section 4</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2049.1">A.2</a></li>
    50384993                     </ul>
    50394994                  </li>
    5040                   <li><em>RFC2068</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2068.1">4.5</a>, <a href="#rfc.xref.RFC2068.2">4.5</a>, <a href="#RFC2068"><b>13.2</b></a>, <a href="#rfc.xref.RFC2068.3">B</a><ul>
     4995                  <li><em>RFC2068</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2068.1">4.5</a>, <a href="#rfc.xref.RFC2068.2">4.5</a>, <a href="#RFC2068"><b>14.2</b></a>, <a href="#rfc.xref.RFC2068.3">B</a><ul>
    50414996                        <li><em>Section 10.3</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2068.2">4.5</a></li>
    50424997                        <li><em>Section 10.3.4</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2068.1">4.5</a></li>
    50434998                     </ul>
    50444999                  </li>
    5045                   <li><em>RFC2076</em>&nbsp;&nbsp;<a href="#RFC2076"><b>13.2</b></a>, <a href="#rfc.xref.RFC2076.1">B</a></li>
    5046                   <li><em>RFC2119</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2119.1">1.2</a>, <a href="#RFC2119"><b>13.1</b></a></li>
    5047                   <li><em>RFC2277</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2277.1">5.3</a>, <a href="#RFC2277"><b>13.2</b></a></li>
    5048                   <li><em>RFC2295</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2295.1">8</a>, <a href="#RFC2295"><b>13.2</b></a></li>
    5049                   <li><em>RFC2388</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2388.1">5.5.2</a>, <a href="#RFC2388"><b>13.2</b></a></li>
    5050                   <li><em>RFC2557</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2557.1">9.8</a>, <a href="#RFC2557"><b>13.2</b></a>, <a href="#rfc.xref.RFC2557.2">A.6</a><ul>
     5000                  <li><em>RFC2076</em>&nbsp;&nbsp;<a href="#RFC2076"><b>14.2</b></a>, <a href="#rfc.xref.RFC2076.1">B</a></li>
     5001                  <li><em>RFC2277</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2277.1">5.3</a>, <a href="#RFC2277"><b>14.2</b></a></li>
     5002                  <li><em>RFC2295</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2295.1">8</a>, <a href="#RFC2295"><b>14.2</b></a></li>
     5003                  <li><em>RFC2388</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2388.1">5.5.2</a>, <a href="#RFC2388"><b>14.2</b></a></li>
     5004                  <li><em>RFC2557</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2557.1">9.8</a>, <a href="#RFC2557"><b>14.2</b></a>, <a href="#rfc.xref.RFC2557.2">A.6</a><ul>
    50515005                        <li><em>Section 4</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2557.1">9.8</a></li>
    50525006                     </ul>
    50535007                  </li>
    5054                   <li><em>RFC2616</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.1">1</a>, <a href="#rfc.xref.RFC2616.2">4.5</a>, <a href="#rfc.xref.RFC2616.3">9.4</a>, <a href="#RFC2616"><b>13.2</b></a>, <a href="#rfc.xref.RFC2616.4">E.1</a><ul>
     5008                  <li><em>RFC2616</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.1">1</a>, <a href="#rfc.xref.RFC2616.2">4.5</a>, <a href="#rfc.xref.RFC2616.3">9.4</a>, <a href="#RFC2616"><b>14.2</b></a>, <a href="#rfc.xref.RFC2616.4">E.1</a><ul>
    50555009                        <li><em>Section 10.3.8</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.2">4.5</a></li>
    50565010                        <li><em>Section 14.4</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.3">9.4</a></li>
    50575011                     </ul>
    50585012                  </li>
    5059                   <li><em>RFC2817</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2817.1">10.2</a>, <a href="#RFC2817"><b>13.2</b></a>, <a href="#rfc.xref.RFC2817.2">C</a>, <a href="#rfc.xref.RFC2817.3">C</a>, <a href="#rfc.xref.RFC2817.4">C</a><ul>
     5013                  <li><em>RFC2817</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2817.1">10.2</a>, <a href="#RFC2817"><b>14.2</b></a>, <a href="#rfc.xref.RFC2817.2">C</a>, <a href="#rfc.xref.RFC2817.3">C</a>, <a href="#rfc.xref.RFC2817.4">C</a><ul>
    50605014                        <li><em>Section 7.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2817.1">10.2</a>, <a href="#rfc.xref.RFC2817.3">C</a></li>
    50615015                     </ul>
    50625016                  </li>
    5063                   <li><em>RFC3629</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3629.1">5.3</a>, <a href="#RFC3629"><b>13.2</b></a></li>
    5064                   <li><em>RFC3864</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3864.1">3.1</a>, <a href="#rfc.xref.RFC3864.2">3.1</a>, <a href="#rfc.xref.RFC3864.3">10.3</a>, <a href="#RFC3864"><b>13.2</b></a><ul>
     5017                  <li><em>RFC3629</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3629.1">5.3</a>, <a href="#RFC3629"><b>14.2</b></a></li>
     5018                  <li><em>RFC3864</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3864.1">3.1</a>, <a href="#rfc.xref.RFC3864.2">3.1</a>, <a href="#rfc.xref.RFC3864.3">10.3</a>, <a href="#RFC3864"><b>14.2</b></a><ul>
    50655019                        <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3864.2">3.1</a></li>
    50665020                     </ul>
    50675021                  </li>
    5068                   <li><em>RFC3986</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.1">9.13</a>, <a href="#rfc.xref.RFC3986.2">9.13</a>, <a href="#RFC3986"><b>13.1</b></a><ul>
     5022                  <li><em>RFC3986</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.1">9.13</a>, <a href="#rfc.xref.RFC3986.2">9.13</a>, <a href="#RFC3986"><b>14.1</b></a><ul>
    50695023                        <li><em>Section 4.2</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.1">9.13</a></li>
    50705024                        <li><em>Section 5</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.2">9.13</a></li>
    50715025                     </ul>
    50725026                  </li>
    5073                   <li><em>RFC4288</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4288.1">5.5</a>, <a href="#RFC4288"><b>13.2</b></a></li>
    5074                   <li><em>RFC4647</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4647.1">9.4</a>, <a href="#rfc.xref.RFC4647.2">9.4</a>, <a href="#rfc.xref.RFC4647.3">9.4</a>, <a href="#rfc.xref.RFC4647.4">9.4</a>, <a href="#RFC4647"><b>13.1</b></a><ul>
     5027                  <li><em>RFC4288</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4288.1">5.5</a>, <a href="#RFC4288"><b>14.2</b></a></li>
     5028                  <li><em>RFC4647</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4647.1">9.4</a>, <a href="#rfc.xref.RFC4647.2">9.4</a>, <a href="#rfc.xref.RFC4647.3">9.4</a>, <a href="#rfc.xref.RFC4647.4">9.4</a>, <a href="#RFC4647"><b>14.1</b></a><ul>
    50755029                        <li><em>Section 2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4647.1">9.4</a></li>
    50765030                        <li><em>Section 2.3</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4647.2">9.4</a></li>
    … …  
    50795033                     </ul>
    50805034                  </li>
    5081                   <li><em>RFC5226</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">2.2</a>, <a href="#rfc.xref.RFC5226.2">4.2</a>, <a href="#rfc.xref.RFC5226.3">5.4.1</a>, <a href="#RFC5226"><b>13.2</b></a><ul>
     5035                  <li><em>RFC5226</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">2.2</a>, <a href="#rfc.xref.RFC5226.2">4.2</a>, <a href="#rfc.xref.RFC5226.3">5.4.1</a>, <a href="#RFC5226"><b>14.2</b></a><ul>
    50825036                        <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">2.2</a>, <a href="#rfc.xref.RFC5226.2">4.2</a>, <a href="#rfc.xref.RFC5226.3">5.4.1</a></li>
    50835037                     </ul>
    50845038                  </li>
    5085                   <li><em>RFC5234</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5234.1">1.3</a>, <a href="#rfc.xref.RFC5234.2">1.3</a>, <a href="#rfc.xref.RFC5234.3">3.1</a>, <a href="#RFC5234"><b>13.1</b></a><ul>
    5086                         <li><em>Appendix B.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5234.2">1.3</a></li>
     5039                  <li><em>RFC5234</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5234.1">3.1</a>, <a href="#rfc.xref.RFC5234.2">11</a>, <a href="#rfc.xref.RFC5234.3">11</a>, <a href="#RFC5234"><b>14.1</b></a><ul>
     5040                        <li><em>Appendix B.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5234.3">11</a></li>
    50875041                     </ul>
    50885042                  </li>
    5089                   <li><em>RFC5322</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5322.1">5.1</a>, <a href="#rfc.xref.RFC5322.2">9.10</a>, <a href="#rfc.xref.RFC5322.3">9.12</a>, <a href="#rfc.xref.RFC5322.4">9.12</a>, <a href="#RFC5322"><b>13.2</b></a>, <a href="#rfc.xref.RFC5322.5">A</a><ul>
     5043                  <li><em>RFC5322</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5322.1">5.1</a>, <a href="#rfc.xref.RFC5322.2">9.10</a>, <a href="#rfc.xref.RFC5322.3">9.12</a>, <a href="#rfc.xref.RFC5322.4">9.12</a>, <a href="#RFC5322"><b>14.2</b></a>, <a href="#rfc.xref.RFC5322.5">A</a><ul>
    50905044                        <li><em>Section 3.3</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5322.1">5.1</a></li>
    50915045                        <li><em>Section 3.4</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5322.3">9.12</a>, <a href="#rfc.xref.RFC5322.4">9.12</a></li>
    … …  
    50935047                     </ul>
    50945048                  </li>
    5095                   <li><em>RFC5646</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5646.1">5.6</a>, <a href="#rfc.xref.RFC5646.2">5.6</a>, <a href="#rfc.xref.RFC5646.3">5.6</a>, <a href="#RFC5646"><b>13.1</b></a><ul>
     5049                  <li><em>RFC5646</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5646.1">5.6</a>, <a href="#rfc.xref.RFC5646.2">5.6</a>, <a href="#rfc.xref.RFC5646.3">5.6</a>, <a href="#RFC5646"><b>14.1</b></a><ul>
    50965050                        <li><em>Section 2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5646.2">5.6</a></li>
    50975051                     </ul>
    50985052                  </li>
    5099                   <li><em>RFC5789</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5789.1">2.3.5</a>, <a href="#RFC5789"><b>13.2</b></a></li>
    5100                   <li><em>RFC5987</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5987.1">3.1</a>, <a href="#RFC5987"><b>13.2</b></a></li>
    5101                   <li><em>RFC6151</em>&nbsp;&nbsp;<a href="#RFC6151"><b>13.2</b></a>, <a href="#rfc.xref.RFC6151.1">C</a></li>
    5102                   <li><em>RFC6266</em>&nbsp;&nbsp;<a href="#RFC6266"><b>13.2</b></a>, <a href="#rfc.xref.RFC6266.1">B</a>, <a href="#rfc.xref.RFC6266.2">C</a></li>
     5053                  <li><em>RFC5789</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5789.1">2.3.5</a>, <a href="#RFC5789"><b>14.2</b></a></li>
     5054                  <li><em>RFC5987</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5987.1">3.1</a>, <a href="#RFC5987"><b>14.2</b></a></li>
     5055                  <li><em>RFC6151</em>&nbsp;&nbsp;<a href="#RFC6151"><b>14.2</b></a>, <a href="#rfc.xref.RFC6151.1">C</a></li>
     5056                  <li><em>RFC6266</em>&nbsp;&nbsp;<a href="#RFC6266"><b>14.2</b></a>, <a href="#rfc.xref.RFC6266.1">B</a>, <a href="#rfc.xref.RFC6266.2">C</a></li>
    51035057               </ul>
    51045058            </li>
    51055059            <li><a id="rfc.index.S" href="#rfc.index.S"><b>S</b></a><ul>
    5106                   <li>Safe Methods&nbsp;&nbsp;<a href="#rfc.iref.s.2"><b>2.1.1</b></a></li>
    5107                   <li>selected representation&nbsp;&nbsp;<a href="#rfc.iref.s.1"><b>1.1</b></a></li>
    5108                   <li>Server header field&nbsp;&nbsp;<a href="#rfc.xref.header.server.1">3.3</a>, <a href="#rfc.iref.s.44"><b>9.17</b></a>, <a href="#rfc.xref.header.server.2">10.3</a>, <a href="#rfc.xref.header.server.3">11.1</a>, <a href="#rfc.xref.header.server.4">C</a></li>
     5060                  <li>Safe Methods&nbsp;&nbsp;<a href="#rfc.iref.s.1"><b>2.1.1</b></a></li>
     5061                  <li>selected representation&nbsp;&nbsp;<a href="#rfc.iref.s.43"><b>7.2</b></a></li>
     5062                  <li>Server header field&nbsp;&nbsp;<a href="#rfc.xref.header.server.1">3.3</a>, <a href="#rfc.iref.s.44"><b>9.17</b></a>, <a href="#rfc.xref.header.server.2">10.3</a>, <a href="#rfc.xref.header.server.3">12.1</a>, <a href="#rfc.xref.header.server.4">C</a></li>
    51095063                  <li>Status Codes&nbsp;&nbsp;
    51105064                     <ul>
    5111                         <li>100 Continue&nbsp;&nbsp;<a href="#rfc.xref.status.100.1">4.1</a>, <a href="#rfc.iref.s.4"><b>4.3.1</b></a>, <a href="#rfc.xref.status.100.2">10.2</a></li>
    5112                         <li>101 Switching Protocols&nbsp;&nbsp;<a href="#rfc.xref.status.101.1">4.1</a>, <a href="#rfc.iref.s.5"><b>4.3.2</b></a>, <a href="#rfc.xref.status.101.2">10.2</a></li>
    5113                         <li>200 OK&nbsp;&nbsp;<a href="#rfc.xref.status.200.1">4.1</a>, <a href="#rfc.iref.s.7"><b>4.4.1</b></a>, <a href="#rfc.xref.status.200.2">10.2</a></li>
    5114                         <li>201 Created&nbsp;&nbsp;<a href="#rfc.xref.status.201.1">4.1</a>, <a href="#rfc.iref.s.8"><b>4.4.2</b></a>, <a href="#rfc.xref.status.201.2">10.2</a></li>
    5115                         <li>202 Accepted&nbsp;&nbsp;<a href="#rfc.xref.status.202.1">4.1</a>, <a href="#rfc.iref.s.9"><b>4.4.3</b></a>, <a href="#rfc.xref.status.202.2">10.2</a></li>
    5116                         <li>203 Non-Authoritative Information&nbsp;&nbsp;<a href="#rfc.xref.status.203.1">4.1</a>, <a href="#rfc.iref.s.10"><b>4.4.4</b></a>, <a href="#rfc.xref.status.203.2">10.2</a>, <a href="#rfc.xref.status.203.3">C</a></li>
    5117                         <li>204 No Content&nbsp;&nbsp;<a href="#rfc.xref.status.204.1">4.1</a>, <a href="#rfc.iref.s.11"><b>4.4.5</b></a>, <a href="#rfc.xref.status.204.2">10.2</a></li>
    5118                         <li>205 Reset Content&nbsp;&nbsp;<a href="#rfc.xref.status.205.1">4.1</a>, <a href="#rfc.iref.s.12"><b>4.4.6</b></a>, <a href="#rfc.xref.status.205.2">10.2</a></li>
    5119                         <li>300 Multiple Choices&nbsp;&nbsp;<a href="#rfc.xref.status.300.1">4.1</a>, <a href="#rfc.iref.s.14"><b>4.5.1</b></a>, <a href="#rfc.xref.status.300.2">10.2</a></li>
    5120                         <li>301 Moved Permanently&nbsp;&nbsp;<a href="#rfc.xref.status.301.1">4.1</a>, <a href="#rfc.iref.s.15"><b>4.5.2</b></a>, <a href="#rfc.xref.status.301.2">10.2</a>, <a href="#rfc.xref.status.301.3">C</a></li>
    5121                         <li>302 Found&nbsp;&nbsp;<a href="#rfc.xref.status.302.1">4.1</a>, <a href="#rfc.iref.s.16"><b>4.5.3</b></a>, <a href="#rfc.xref.status.302.2">10.2</a>, <a href="#rfc.xref.status.302.3">C</a></li>
    5122                         <li>303 See Other&nbsp;&nbsp;<a href="#rfc.xref.status.303.1">4.1</a>, <a href="#rfc.iref.s.17"><b>4.5.4</b></a>, <a href="#rfc.xref.status.303.2">10.2</a></li>
    5123                         <li>305 Use Proxy&nbsp;&nbsp;<a href="#rfc.xref.status.305.1">4.1</a>, <a href="#rfc.iref.s.18"><b>4.5.5</b></a>, <a href="#rfc.xref.status.305.2">10.2</a>, <a href="#rfc.xref.status.305.3">C</a></li>
    5124                         <li>306 (Unused)&nbsp;&nbsp;<a href="#rfc.iref.s.19"><b>4.5.6</b></a>, <a href="#rfc.xref.status.306.1">10.2</a></li>
    5125                         <li>307 Temporary Redirect&nbsp;&nbsp;<a href="#rfc.xref.status.307.1">4.1</a>, <a href="#rfc.iref.s.20"><b>4.5.7</b></a>, <a href="#rfc.xref.status.307.2">10.2</a>, <a href="#rfc.xref.status.307.3">C</a></li>
    5126                         <li>400 Bad Request&nbsp;&nbsp;<a href="#rfc.xref.status.400.1">4.1</a>, <a href="#rfc.iref.s.22"><b>4.6.1</b></a>, <a href="#rfc.xref.status.400.2">10.2</a></li>
    5127                         <li>402 Payment Required&nbsp;&nbsp;<a href="#rfc.xref.status.402.1">4.1</a>, <a href="#rfc.iref.s.23"><b>4.6.2</b></a>, <a href="#rfc.xref.status.402.2">10.2</a></li>
    5128                         <li>403 Forbidden&nbsp;&nbsp;<a href="#rfc.xref.status.403.1">4.1</a>, <a href="#rfc.iref.s.24"><b>4.6.3</b></a>, <a href="#rfc.xref.status.403.2">10.2</a></li>
    5129                         <li>404 Not Found&nbsp;&nbsp;<a href="#rfc.xref.status.404.1">4.1</a>, <a href="#rfc.iref.s.25"><b>4.6.4</b></a>, <a href="#rfc.xref.status.404.2">10.2</a></li>
    5130                         <li>405 Method Not Allowed&nbsp;&nbsp;<a href="#rfc.xref.status.405.1">4.1</a>, <a href="#rfc.iref.s.26"><b>4.6.5</b></a>, <a href="#rfc.xref.status.405.2">10.2</a></li>
    5131                         <li>406 Not Acceptable&nbsp;&nbsp;<a href="#rfc.xref.status.406.1">4.1</a>, <a href="#rfc.iref.s.27"><b>4.6.6</b></a>, <a href="#rfc.xref.status.406.2">10.2</a></li>
    5132                         <li>408 Request Timeout&nbsp;&nbsp;<a href="#rfc.xref.status.408.1">4.1</a>, <a href="#rfc.iref.s.28"><b>4.6.7</b></a>, <a href="#rfc.xref.status.408.2">10.2</a></li>
    5133                         <li>409 Conflict&nbsp;&nbsp;<a href="#rfc.xref.status.409.1">4.1</a>, <a href="#rfc.iref.s.29"><b>4.6.8</b></a>, <a href="#rfc.xref.status.409.2">10.2</a></li>
    5134                         <li>410 Gone&nbsp;&nbsp;<a href="#rfc.xref.status.410.1">4.1</a>, <a href="#rfc.iref.s.30"><b>4.6.9</b></a>, <a href="#rfc.xref.status.410.2">10.2</a></li>
    5135                         <li>411 Length Required&nbsp;&nbsp;<a href="#rfc.xref.status.411.1">4.1</a>, <a href="#rfc.iref.s.31"><b>4.6.10</b></a>, <a href="#rfc.xref.status.411.2">10.2</a></li>
    5136                         <li>413 Request Representation Too Large&nbsp;&nbsp;<a href="#rfc.xref.status.413.1">4.1</a>, <a href="#rfc.iref.s.32"><b>4.6.11</b></a>, <a href="#rfc.xref.status.413.2">10.2</a></li>
    5137                         <li>414 URI Too Long&nbsp;&nbsp;<a href="#rfc.xref.status.414.1">4.1</a>, <a href="#rfc.iref.s.33"><b>4.6.12</b></a>, <a href="#rfc.xref.status.414.2">10.2</a></li>
    5138                         <li>415 Unsupported Media Type&nbsp;&nbsp;<a href="#rfc.xref.status.415.1">4.1</a>, <a href="#rfc.iref.s.34"><b>4.6.13</b></a>, <a href="#rfc.xref.status.415.2">10.2</a></li>
    5139                         <li>417 Expectation Failed&nbsp;&nbsp;<a href="#rfc.xref.status.417.1">4.1</a>, <a href="#rfc.iref.s.35"><b>4.6.14</b></a>, <a href="#rfc.xref.status.417.2">10.2</a></li>
    5140                         <li>426 Upgrade Required&nbsp;&nbsp;<a href="#rfc.xref.status.426.1">4.1</a>, <a href="#rfc.iref.s.36"><b>4.6.15</b></a>, <a href="#rfc.xref.status.426.2">10.2</a>, <a href="#rfc.xref.status.426.3">C</a></li>
    5141                         <li>500 Internal Server Error&nbsp;&nbsp;<a href="#rfc.xref.status.500.1">4.1</a>, <a href="#rfc.iref.s.38"><b>4.7.1</b></a>, <a href="#rfc.xref.status.500.2">10.2</a></li>
    5142                         <li>501 Not Implemented&nbsp;&nbsp;<a href="#rfc.xref.status.501.1">4.1</a>, <a href="#rfc.iref.s.39"><b>4.7.2</b></a>, <a href="#rfc.xref.status.501.2">10.2</a></li>
    5143                         <li>502 Bad Gateway&nbsp;&nbsp;<a href="#rfc.xref.status.502.1">4.1</a>, <a href="#rfc.iref.s.40"><b>4.7.3</b></a>, <a href="#rfc.xref.status.502.2">10.2</a></li>
    5144                         <li>503 Service Unavailable&nbsp;&nbsp;<a href="#rfc.xref.status.503.1">4.1</a>, <a href="#rfc.iref.s.41"><b>4.7.4</b></a>, <a href="#rfc.xref.status.503.2">10.2</a></li>
    5145                         <li>504 Gateway Timeout&nbsp;&nbsp;<a href="#rfc.xref.status.504.1">4.1</a>, <a href="#rfc.iref.s.42"><b>4.7.5</b></a>, <a href="#rfc.xref.status.504.2">10.2</a></li>
    5146                         <li>505 HTTP Version Not Supported&nbsp;&nbsp;<a href="#rfc.xref.status.505.1">4.1</a>, <a href="#rfc.iref.s.43"><b>4.7.6</b></a>, <a href="#rfc.xref.status.505.2">10.2</a></li>
     5065                        <li>100 Continue&nbsp;&nbsp;<a href="#rfc.xref.status.100.1">4.1</a>, <a href="#rfc.iref.s.3"><b>4.3.1</b></a>, <a href="#rfc.xref.status.100.2">10.2</a></li>
     5066                        <li>101 Switching Protocols&nbsp;&nbsp;<a href="#rfc.xref.status.101.1">4.1</a>, <a href="#rfc.iref.s.4"><b>4.3.2</b></a>, <a href="#rfc.xref.status.101.2">10.2</a></li>
     5067                        <li>200 OK&nbsp;&nbsp;<a href="#rfc.xref.status.200.1">4.1</a>, <a href="#rfc.iref.s.6"><b>4.4.1</b></a>, <a href="#rfc.xref.status.200.2">10.2</a></li>
     5068                        <li>201 Created&nbsp;&nbsp;<a href="#rfc.xref.status.201.1">4.1</a>, <a href="#rfc.iref.s.7"><b>4.4.2</b></a>, <a href="#rfc.xref.status.201.2">10.2</a></li>
     5069                        <li>202 Accepted&nbsp;&nbsp;<a href="#rfc.xref.status.202.1">4.1</a>, <a href="#rfc.iref.s.8"><b>4.4.3</b></a>, <a href="#rfc.xref.status.202.2">10.2</a></li>
     5070                        <li>203 Non-Authoritative Information&nbsp;&nbsp;<a href="#rfc.xref.status.203.1">4.1</a>, <a href="#rfc.iref.s.9"><b>4.4.4</b></a>, <a href="#rfc.xref.status.203.2">10.2</a>, <a href="#rfc.xref.status.203.3">C</a></li>
     5071                        <li>204 No Content&nbsp;&nbsp;<a href="#rfc.xref.status.204.1">4.1</a>, <a href="#rfc.iref.s.10"><b>4.4.5</b></a>, <a href="#rfc.xref.status.204.2">10.2</a></li>
     5072                        <li>205 Reset Content&nbsp;&nbsp;<a href="#rfc.xref.status.205.1">4.1</a>, <a href="#rfc.iref.s.11"><b>4.4.6</b></a>, <a href="#rfc.xref.status.205.2">10.2</a></li>
     5073                        <li>300 Multiple Choices&nbsp;&nbsp;<a href="#rfc.xref.status.300.1">4.1</a>, <a href="#rfc.iref.s.13"><b>4.5.1</b></a>, <a href="#rfc.xref.status.300.2">10.2</a></li>
     5074                        <li>301 Moved Permanently&nbsp;&nbsp;<a href="#rfc.xref.status.301.1">4.1</a>, <a href="#rfc.iref.s.14"><b>4.5.2</b></a>, <a href="#rfc.xref.status.301.2">10.2</a>, <a href="#rfc.xref.status.301.3">C</a></li>
     5075                        <li>302 Found&nbsp;&nbsp;<a href="#rfc.xref.status.302.1">4.1</a>, <a href="#rfc.iref.s.15"><b>4.5.3</b></a>, <a href="#rfc.xref.status.302.2">10.2</a>, <a href="#rfc.xref.status.302.3">C</a></li>
     5076                        <li>303 See Other&nbsp;&nbsp;<a href="#rfc.xref.status.303.1">4.1</a>, <a href="#rfc.iref.s.16"><b>4.5.4</b></a>, <a href="#rfc.xref.status.303.2">10.2</a></li>
     5077                        <li>305 Use Proxy&nbsp;&nbsp;<a href="#rfc.xref.status.305.1">4.1</a>, <a href="#rfc.iref.s.17"><b>4.5.5</b></a>, <a href="#rfc.xref.status.305.2">10.2</a>, <a href="#rfc.xref.status.305.3">C</a></li>
     5078                        <li>306 (Unused)&nbsp;&nbsp;<a href="#rfc.iref.s.18"><b>4.5.6</b></a>, <a href="#rfc.xref.status.306.1">10.2</a></li>
     5079                        <li>307 Temporary Redirect&nbsp;&nbsp;<a href="#rfc.xref.status.307.1">4.1</a>, <a href="#rfc.iref.s.19"><b>4.5.7</b></a>, <a href="#rfc.xref.status.307.2">10.2</a>, <a href="#rfc.xref.status.307.3">C</a></li>
     5080                        <li>400 Bad Request&nbsp;&nbsp;<a href="#rfc.xref.status.400.1">4.1</a>, <a href="#rfc.iref.s.21"><b>4.6.1</b></a>, <a href="#rfc.xref.status.400.2">10.2</a></li>
     5081                        <li>402 Payment Required&nbsp;&nbsp;<a href="#rfc.xref.status.402.1">4.1</a>, <a href="#rfc.iref.s.22"><b>4.6.2</b></a>, <a href="#rfc.xref.status.402.2">10.2</a></li>
     5082                        <li>403 Forbidden&nbsp;&nbsp;<a href="#rfc.xref.status.403.1">4.1</a>, <a href="#rfc.iref.s.23"><b>4.6.3</b></a>, <a href="#rfc.xref.status.403.2">10.2</a></li>
     5083                        <li>404 Not Found&nbsp;&nbsp;<a href="#rfc.xref.status.404.1">4.1</a>, <a href="#rfc.iref.s.24"><b>4.6.4</b></a>, <a href="#rfc.xref.status.404.2">10.2</a></li>
     5084                        <li>405 Method Not Allowed&nbsp;&nbsp;<a href="#rfc.xref.status.405.1">4.1</a>, <a href="#rfc.iref.s.25"><b>4.6.5</b></a>, <a href="#rfc.xref.status.405.2">10.2</a></li>
     5085                        <li>406 Not Acceptable&nbsp;&nbsp;<a href="#rfc.xref.status.406.1">4.1</a>, <a href="#rfc.iref.s.26"><b>4.6.6</b></a>, <a href="#rfc.xref.status.406.2">10.2</a></li>
     5086                        <li>408 Request Timeout&nbsp;&nbsp;<a href="#rfc.xref.status.408.1">4.1</a>, <a href="#rfc.iref.s.27"><b>4.6.7</b></a>, <a href="#rfc.xref.status.408.2">10.2</a></li>
     5087                        <li>409 Conflict&nbsp;&nbsp;<a href="#rfc.xref.status.409.1">4.1</a>, <a href="#rfc.iref.s.28"><b>4.6.8</b></a>, <a href="#rfc.xref.status.409.2">10.2</a></li>
     5088                        <li>410 Gone&nbsp;&nbsp;<a href="#rfc.xref.status.410.1">4.1</a>, <a href="#rfc.iref.s.29"><b>4.6.9</b></a>, <a href="#rfc.xref.status.410.2">10.2</a></li>
     5089                        <li>411 Length Required&nbsp;&nbsp;<a href="#rfc.xref.status.411.1">4.1</a>, <a href="#rfc.iref.s.30"><b>4.6.10</b></a>, <a href="#rfc.xref.status.411.2">10.2</a></li>
     5090                        <li>413 Request Representation Too Large&nbsp;&nbsp;<a href="#rfc.xref.status.413.1">4.1</a>, <a href="#rfc.iref.s.31"><b>4.6.11</b></a>, <a href="#rfc.xref.status.413.2">10.2</a></li>
     5091                        <li>414 URI Too Long&nbsp;&nbsp;<a href="#rfc.xref.status.414.1">4.1</a>, <a href="#rfc.iref.s.32"><b>4.6.12</b></a>, <a href="#rfc.xref.status.414.2">10.2</a></li>
     5092                        <li>415 Unsupported Media Type&nbsp;&nbsp;<a href="#rfc.xref.status.415.1">4.1</a>, <a href="#rfc.iref.s.33"><b>4.6.13</b></a>, <a href="#rfc.xref.status.415.2">10.2</a></li>
     5093                        <li>417 Expectation Failed&nbsp;&nbsp;<a href="#rfc.xref.status.417.1">4.1</a>, <a href="#rfc.iref.s.34"><b>4.6.14</b></a>, <a href="#rfc.xref.status.417.2">10.2</a></li>
     5094                        <li>426 Upgrade Required&nbsp;&nbsp;<a href="#rfc.xref.status.426.1">4.1</a>, <a href="#rfc.iref.s.35"><b>4.6.15</b></a>, <a href="#rfc.xref.status.426.2">10.2</a>, <a href="#rfc.xref.status.426.3">C</a></li>
     5095                        <li>500 Internal Server Error&nbsp;&nbsp;<a href="#rfc.xref.status.500.1">4.1</a>, <a href="#rfc.iref.s.37"><b>4.7.1</b></a>, <a href="#rfc.xref.status.500.2">10.2</a></li>
     5096                        <li>501 Not Implemented&nbsp;&nbsp;<a href="#rfc.xref.status.501.1">4.1</a>, <a href="#rfc.iref.s.38"><b>4.7.2</b></a>, <a href="#rfc.xref.status.501.2">10.2</a></li>
     5097                        <li>502 Bad Gateway&nbsp;&nbsp;<a href="#rfc.xref.status.502.1">4.1</a>, <a href="#rfc.iref.s.39"><b>4.7.3</b></a>, <a href="#rfc.xref.status.502.2">10.2</a></li>
     5098                        <li>503 Service Unavailable&nbsp;&nbsp;<a href="#rfc.xref.status.503.1">4.1</a>, <a href="#rfc.iref.s.40"><b>4.7.4</b></a>, <a href="#rfc.xref.status.503.2">10.2</a></li>
     5099                        <li>504 Gateway Timeout&nbsp;&nbsp;<a href="#rfc.xref.status.504.1">4.1</a>, <a href="#rfc.iref.s.41"><b>4.7.5</b></a>, <a href="#rfc.xref.status.504.2">10.2</a></li>
     5100                        <li>505 HTTP Version Not Supported&nbsp;&nbsp;<a href="#rfc.xref.status.505.1">4.1</a>, <a href="#rfc.iref.s.42"><b>4.7.6</b></a>, <a href="#rfc.xref.status.505.2">10.2</a></li>
    51475101                     </ul>
    51485102                  </li>
    51495103                  <li>Status Codes Classes&nbsp;&nbsp;
    51505104                     <ul>
    5151                         <li>1xx Informational&nbsp;&nbsp;<a href="#rfc.iref.s.3"><b>4.3</b></a></li>
    5152                         <li>2xx Successful&nbsp;&nbsp;<a href="#rfc.iref.s.6"><b>4.4</b></a></li>
    5153                         <li>3xx Redirection&nbsp;&nbsp;<a href="#rfc.iref.s.13"><b>4.5</b></a>, <a href="#rfc.xref.status.3xx.1">C</a></li>
    5154                         <li>4xx Client Error&nbsp;&nbsp;<a href="#rfc.iref.s.21"><b>4.6</b></a></li>
    5155                         <li>5xx Server Error&nbsp;&nbsp;<a href="#rfc.iref.s.37"><b>4.7</b></a></li>
     5105                        <li>1xx Informational&nbsp;&nbsp;<a href="#rfc.iref.s.2"><b>4.3</b></a></li>
     5106                        <li>2xx Successful&nbsp;&nbsp;<a href="#rfc.iref.s.5"><b>4.4</b></a></li>
     5107                        <li>3xx Redirection&nbsp;&nbsp;<a href="#rfc.iref.s.12"><b>4.5</b></a>, <a href="#rfc.xref.status.3xx.1">C</a></li>
     5108                        <li>4xx Client Error&nbsp;&nbsp;<a href="#rfc.iref.s.20"><b>4.6</b></a></li>
     5109                        <li>5xx Server Error&nbsp;&nbsp;<a href="#rfc.iref.s.36"><b>4.7</b></a></li>
    51565110                     </ul>
    51575111                  </li>
    … …  
    51595113            </li>
    51605114            <li><a id="rfc.index.T" href="#rfc.index.T"><b>T</b></a><ul>
    5161                   <li>TRACE method&nbsp;&nbsp;<a href="#rfc.iref.t.1"><b>2.3.7</b></a>, <a href="#rfc.xref.TRACE.1">9.14</a>, <a href="#rfc.xref.TRACE.2">10.1</a>, <a href="#rfc.xref.TRACE.3">11.1</a></li>
     5115                  <li>TRACE method&nbsp;&nbsp;<a href="#rfc.iref.t.1"><b>2.3.7</b></a>, <a href="#rfc.xref.TRACE.1">9.14</a>, <a href="#rfc.xref.TRACE.2">10.1</a>, <a href="#rfc.xref.TRACE.3">12.1</a></li>
    51625116               </ul>
    51635117            </li>
    51645118            <li><a id="rfc.index.U" href="#rfc.index.U"><b>U</b></a><ul>
    5165                   <li>User-Agent header field&nbsp;&nbsp;<a href="#rfc.xref.header.user-agent.1">3.2</a>, <a href="#rfc.xref.header.user-agent.2">8.1</a>, <a href="#rfc.iref.u.1"><b>9.18</b></a>, <a href="#rfc.xref.header.user-agent.3">10.3</a>, <a href="#rfc.xref.header.user-agent.4">11.1</a></li>
     5119                  <li>User-Agent header field&nbsp;&nbsp;<a href="#rfc.xref.header.user-agent.1">3.2</a>, <a href="#rfc.xref.header.user-agent.2">8.1</a>, <a href="#rfc.iref.u.1"><b>9.18</b></a>, <a href="#rfc.xref.header.user-agent.3">10.3</a>, <a href="#rfc.xref.header.user-agent.4">12.1</a></li>
    51665120               </ul>
    51675121            </li>

  • draft-ietf-httpbis/latest/p2-semantics.xml

    r1778 r1781  
    188188   distributed, collaborative, hypertext information systems. HTTP has been in
    189189   use by the World Wide Web global information initiative since 1990. This
    190    document is Part 2 of the seven-part specification that defines the protocol
    191    referred to as "HTTP/1.1" and, taken together, obsoletes RFC 2616.
    192 </t>
    193 <t>
    194    Part 2 defines the semantics of HTTP messages as expressed by request
     190   document is Part 2 of the six-part specification that defines the protocol
     191   referred to as "HTTP/1.1".
     192</t>
     193<t>
     194   Part 2 defines the semantics of HTTP messages, as expressed by request
    195195   methods, request header fields, response status codes, and response header
    196    fields. Furthermore, it defines HTTP message content, metadata, and content
    197    negotiation.
     196   fields, the payload of messages as metadata and body content, and the
     197   mechanisms for content negotiation.
    198198</t>
    199199</abstract>
    … …  
    219219<section title="Introduction" anchor="introduction">
    220220<t>
    221    This document defines HTTP/1.1 request and response semantics.  Each HTTP
    222    message, as defined in &messaging;, is in the form of either a request or
    223    a response.  An HTTP server listens on a connection for HTTP requests and
    224    responds to each request, in the order received on that connection, with
    225    one or more HTTP response messages.  This document defines the commonly
    226    agreed upon semantics of the HTTP uniform interface, the intentions defined
    227    by each request method, and the various response messages that might be
    228    expected as a result of applying that method to the target resource.
    229 </t>
    230 <t>
    231    Furthermore, it defines HTTP/1.1 message payloads (a.k.a., content), the
    232    associated metadata header fields that define how the payload is intended
    233    to be interpreted by a recipient, the request header fields that
    234    might influence content selection, and the various selection algorithms
    235    that are collectively referred to as HTTP content negotiation.
    236 </t>
    237 <t>
     221   This document defines HTTP/1.1 request and response semantics in terms of
     222   the architecture, syntax notation, and conformance criteria defined in
     223   &architecture;. Each HTTP message is either a request or a response.
     224   A server listens on a connection for a request, parses each message
     225   received, interprets the message semantics in relation to the identified
     226   request target, and responds to that request with one or more response
     227   messages.
     228</t>
     229<t>
     230   HTTP provides a uniform interface for interacting with resources regardless
     231   of their type, nature, or implementation.  HTTP semantics includes the
     232   intentions defined by each request method, extensions to those semantics
     233   that might be described in request header fields, the meaning of status
     234   codes to indicate a machine-readable response, and additional control data
     235   and resource metadata that might be given in response header fields.
     236</t>
     237<t><iref item="content negotiation"/>
     238   In addition, this document defines the payload of messages (a.k.a.,
     239   content), the associated metadata header fields that define how the payload
     240   is intended to be interpreted by a recipient, the request header fields
     241   that might influence content selection, and the various selection
     242   algorithms that are collectively referred to as
     243   "<x:dfn>content negotiation</x:dfn>".
     244</t>
     245<x:note><t>
    238246   This document is currently disorganized in order to minimize the changes
    239247   between drafts and enable reviewers to see the smaller errata changes.
    … …  
    245253   reflects how widely dispersed these topics and associated requirements
    246254   had become in <xref target="RFC2616"/>.
    247 </t>
    248 
    249 <section title="Terminology" anchor="terminology">
    250 <t>
    251    This specification uses a number of terms to refer to the roles
    252    played by participants in, and objects of, the HTTP communication.
    253 </t>
    254 <t>
    255   <iref item="content negotiation"/>
    256   <x:dfn>content negotiation</x:dfn>
    257   <list>
    258     <t>
    259       The mechanism for selecting the appropriate representation when
    260       servicing a request. The representation in any response
    261       can be negotiated (including error responses).
    262     </t>
    263   </list>
    264 </t>
    265 <t>
    266   <iref primary="true" item="selected representation"/>
    267   <x:dfn>selected representation</x:dfn>
    268   <list>
    269     <t>
    270       The current representation of the target resource that would have been
    271       selected in a successful response if the same request had used the
    272       method GET and excluded any conditional request header fields.
    273     </t>
    274   </list>
    275 </t>
    276 </section>
    277 
    278 <section title="Conformance and Error Handling" anchor="intro.conformance.and.error.handling">
    279 <t>
    280    The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
    281    "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
    282    document are to be interpreted as described in <xref target="RFC2119"/>.
    283 </t>
    284 <t>
    285    This specification targets conformance criteria according to the role of
    286    a participant in HTTP communication.  Hence, HTTP requirements are placed
    287    on senders, recipients, clients, servers, user agents, intermediaries,
    288    origin servers, proxies, gateways, or caches, depending on what behavior
    289    is being constrained by the requirement. See &architecture; for definitions
    290    of these terms.
    291 </t>
    292 <t>
    293    The verb "generate" is used instead of "send" where a requirement
    294    differentiates between creating a protocol element and merely forwarding a
    295    received element downstream.
    296 </t>
    297 <t>
    298    An implementation is considered conformant if it complies with all of the
    299    requirements associated with the roles it partakes in HTTP. Note that
    300    SHOULD-level requirements are relevant here, unless one of the documented
    301    exceptions is applicable.
    302 </t>
    303 <t>
    304    This document also uses ABNF to define valid protocol elements
    305    (<xref target="notation"/>).
    306    In addition to the prose requirements placed upon them, senders &MUST-NOT;
    307    generate protocol elements that do not match the grammar defined by the
    308    ABNF rules for those protocol elements that are applicable to the sender's
    309    role. If a received protocol element is processed, the recipient &MUST; be
    310    able to parse any value that would match the ABNF rules for that protocol
    311    element, excluding only those rules not applicable to the recipient's role.
    312 </t>
    313 <t>
    314    Unless noted otherwise, a recipient &MAY; attempt to recover a usable
    315    protocol element from an invalid construct.  HTTP does not define
    316    specific error handling mechanisms except when they have a direct impact
    317    on security, since different applications of the protocol require
    318    different error handling strategies.  For example, a Web browser might
    319    wish to transparently recover from a response where the
    320    <x:ref>Location</x:ref> header field doesn't parse according to the ABNF,
    321    whereas a systems control client might consider any form of error recovery
    322    to be dangerous.
    323 </t>
    324 </section>
    325 
    326 <section title="Syntax Notation" anchor="notation">
    327   <x:anchor-alias value="ALPHA"/>
    328   <x:anchor-alias value="CR"/>
    329   <x:anchor-alias value="DIGIT"/>
    330   <x:anchor-alias value="LF"/>
    331   <x:anchor-alias value="OCTET"/>
    332   <x:anchor-alias value="SP"/>
    333   <x:anchor-alias value="VCHAR"/>
    334 <t>
    335    This specification uses the Augmented Backus-Naur Form (ABNF) notation
    336    of <xref target="RFC5234"/> with the list rule extension defined in
    337    &notation;.  <xref target="collected.abnf"/> shows the collected ABNF
    338    with the list rule expanded.
    339 </t>
    340 <t>
    341   The following core rules are included by
    342   reference, as defined in <xref target="RFC5234" x:fmt="," x:sec="B.1"/>:
    343   ALPHA (letters), CR (carriage return), CRLF (CR LF), CTL (controls),
    344   DIGIT (decimal 0-9), DQUOTE (double quote),
    345   HEXDIG (hexadecimal 0-9/A-F/a-f), HTAB (horizontal tab), LF (line feed),
    346   OCTET (any 8-bit sequence of data), SP (space), and
    347   VCHAR (any visible US-ASCII character).
    348 </t>
    349 
    350 <section title="Core Rules" anchor="core.rules">
    351   <x:anchor-alias value="quoted-string"/>
    352   <x:anchor-alias value="token"/>
    353   <x:anchor-alias value="word"/>
    354   <x:anchor-alias value="BWS"/>
    355   <x:anchor-alias value="OWS"/>
    356   <x:anchor-alias value="RWS"/>
    357 <t>
    358   The core rules below are defined in <xref target="Part1"/>:
    359 </t>
    360 <figure><artwork type="abnf2616">
    361   <x:ref>BWS</x:ref>           = &lt;BWS, defined in &whitespace;&gt;
    362   <x:ref>OWS</x:ref>           = &lt;OWS, defined in &whitespace;&gt;
    363   <x:ref>RWS</x:ref>           = &lt;RWS, defined in &whitespace;&gt;
    364   <x:ref>quoted-string</x:ref> = &lt;quoted-string, defined in &field-components;&gt;
    365   <x:ref>token</x:ref>         = &lt;token, defined in &field-components;&gt;
    366   <x:ref>word</x:ref>          = &lt;word, defined in &field-components;&gt;
    367 </artwork></figure>
    368 </section>
    369 
    370 <section title="ABNF Rules defined in other Parts of the Specification" anchor="abnf.dependencies">
    371   <x:anchor-alias value="absolute-URI"/>
    372   <x:anchor-alias value="comment"/>
    373   <x:anchor-alias value="partial-URI"/>
    374   <x:anchor-alias value="qvalue"/>
    375   <x:anchor-alias value="URI-reference"/>
    376 <t>
    377   The ABNF rules below are defined in other parts:
    378 </t>
    379 <figure><!--Part1--><artwork type="abnf2616">
    380   <x:ref>absolute-URI</x:ref>  = &lt;absolute-URI, defined in &uri;&gt;
    381   <x:ref>comment</x:ref>       = &lt;comment, defined in &field-components;&gt;
    382   <x:ref>partial-URI</x:ref>   = &lt;partial-URI, defined in &uri;&gt;
    383   <x:ref>qvalue</x:ref>        = &lt;qvalue, defined in &qvalue;&gt;
    384   <x:ref>URI-reference</x:ref> = &lt;URI-reference, defined in &uri;&gt;
    385 </artwork></figure>
    386 </section>
    387 </section>
     255</t></x:note>
    388256</section>
    389257
    … …  
    27812649  <c>Expires</c> <c>&header-expires;</c>
    27822650</texttable>
     2651<t><iref primary="true" item="selected representation"/>
     2652   We use the term "<x:dfn>selected representation</x:dfn>" to refer to the
     2653   the current representation of a target resource that would have been
     2654   selected in a successful response if the same request had used the
     2655   method GET and excluded any conditional request header fields.
     2656</t>
    27832657<t>
    27842658   Additional header fields define metadata about the selected
    … …  
    37973671    &Note; Some recipients attempt to recover from Location fields
    37983672    that are not valid URI references. This specification does not mandate or
    3799     define such processing, but does allow it (see <xref target="intro.conformance.and.error.handling"/>).
     3673    define such processing, but does allow it.
    38003674  </t>
    38013675</x:note>
    … …  
    44624336</section>
    44634337
     4338<section title="ABNF Rules Defined Elsewhere" anchor="abnf.dependencies">
     4339  <x:anchor-alias value="ALPHA"/>
     4340  <x:anchor-alias value="CR"/>
     4341  <x:anchor-alias value="DIGIT"/>
     4342  <x:anchor-alias value="LF"/>
     4343  <x:anchor-alias value="OCTET"/>
     4344  <x:anchor-alias value="SP"/>
     4345  <x:anchor-alias value="VCHAR"/>
     4346  <x:anchor-alias value="BWS"/>
     4347  <x:anchor-alias value="OWS"/>
     4348  <x:anchor-alias value="RWS"/>
     4349  <x:anchor-alias value="absolute-URI"/>
     4350  <x:anchor-alias value="comment"/>
     4351  <x:anchor-alias value="partial-URI"/>
     4352  <x:anchor-alias value="qvalue"/>
     4353  <x:anchor-alias value="URI-reference"/>
     4354  <x:anchor-alias value="quoted-string"/>
     4355  <x:anchor-alias value="token"/>
     4356  <x:anchor-alias value="word"/>
     4357<t>
     4358   This specification uses the Augmented Backus-Naur Form (ABNF) notation
     4359   of <xref target="RFC5234"/> with the list rule extension defined in
     4360   &notation;.  <xref target="collected.abnf"/> shows the collected ABNF
     4361   with the list rule expanded.
     4362</t>
     4363<t>
     4364   The following core rules are included by
     4365   reference, as defined in <xref target="RFC5234" x:fmt="," x:sec="B.1"/>:
     4366   ALPHA (letters), CR (carriage return), CRLF (CR LF), CTL (controls),
     4367   DIGIT (decimal 0-9), DQUOTE (double quote),
     4368   HEXDIG (hexadecimal 0-9/A-F/a-f), HTAB (horizontal tab), LF (line feed),
     4369   OCTET (any 8-bit sequence of data), SP (space), and
     4370   VCHAR (any visible US-ASCII character).
     4371</t>
     4372<t>
     4373   The ABNF rules below are defined in other parts:
     4374</t>
     4375<figure><artwork type="abnf2616">
     4376  <x:ref>BWS</x:ref>           = &lt;BWS, defined in &whitespace;&gt;
     4377  <x:ref>OWS</x:ref>           = &lt;OWS, defined in &whitespace;&gt;
     4378  <x:ref>RWS</x:ref>           = &lt;RWS, defined in &whitespace;&gt;
     4379  <x:ref>URI-reference</x:ref> = &lt;URI-reference, defined in &uri;&gt;
     4380  <x:ref>absolute-URI</x:ref>  = &lt;absolute-URI, defined in &uri;&gt;
     4381  <x:ref>partial-URI</x:ref>   = &lt;partial-URI, defined in &uri;&gt;
     4382  <x:ref>quoted-string</x:ref> = &lt;quoted-string, defined in &field-components;&gt;
     4383  <x:ref>qvalue</x:ref>        = &lt;qvalue, defined in &qvalue;&gt;
     4384  <x:ref>token</x:ref>         = &lt;token, defined in &field-components;&gt;
     4385  <x:ref>word</x:ref>          = &lt;word, defined in &field-components;&gt;
     4386  <x:ref>comment</x:ref>       = &lt;comment, defined in &field-components;&gt;
     4387</artwork></figure>
     4388</section>
     4389
    44644390<section title="Security Considerations" anchor="security.considerations">
    44654391<t>
    … …  
    48714797  <seriesInfo name="RFC" value="2046"/>
    48724798</reference>
    4873 
     4799<!--
    48744800<reference anchor="RFC2119">
    48754801  <front>
    … …  
    48844810  <seriesInfo name="RFC" value="2119"/>
    48854811</reference>
    4886 
     4812-->
    48874813<reference anchor="RFC3986">
    48884814 <front>
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