Ignore:
Timestamp:
Dec 9, 2012, 7:44:14 AM (7 years ago)
Author:
fielding@…
Message:

Reference BCP numbers when informative and not section specific; Note added requirement on URI consistency with method semantics; partly addresses #419

File:
1 edited

Legend:

Unmodified
Added
Removed

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

    r2045 r2046  
    449449  }
    450450  @bottom-center {
    451        content: "Expires June 11, 2013";
     451       content: "Expires June 12, 2013";
    452452  }
    453453  @bottom-right {
    … …  
    496496      <meta name="dct.creator" content="Reschke, J. F.">
    497497      <meta name="dct.identifier" content="urn:ietf:id:draft-ietf-httpbis-p2-semantics-latest">
    498       <meta name="dct.issued" scheme="ISO8601" content="2012-12-08">
     498      <meta name="dct.issued" scheme="ISO8601" content="2012-12-09">
    499499      <meta name="dct.replaces" content="urn:ietf:rfc:2616">
    500500      <meta name="dct.abstract" content="The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypertext information systems. This document defines the semantics of HTTP/1.1 messages, as expressed by request methods, request header fields, response status codes, and response header fields, along with the payload of messages (metadata and body content) and mechanisms for content negotiation.">
    … …  
    524524            <tr>
    525525               <td class="left">Intended status: Standards Track</td>
    526                <td class="right">December 8, 2012</td>
     526               <td class="right">December 9, 2012</td>
    527527            </tr>
    528528            <tr>
    529                <td class="left">Expires: June 11, 2013</td>
     529               <td class="left">Expires: June 12, 2013</td>
    530530               <td class="right"></td>
    531531            </tr>
    … …  
    555555         in progress”.
    556556      </p>
    557       <p>This Internet-Draft will expire on June 11, 2013.</p>
     557      <p>This Internet-Draft will expire on June 12, 2013.</p>
    558558      <h1><a id="rfc.copyrightnotice" href="#rfc.copyrightnotice">Copyright Notice</a></h1>
    559559      <p>Copyright © 2012 IETF Trust and the persons identified as the document authors. All rights reserved.</p>
    … …  
    581581         <li><a href="#rfc.section.3">3.</a>&nbsp;&nbsp;&nbsp;<a href="#representations">Representations</a><ul>
    582582               <li><a href="#rfc.section.3.1">3.1</a>&nbsp;&nbsp;&nbsp;<a href="#representation.metadata">Representation Metadata</a><ul>
    583                      <li><a href="#rfc.section.3.1.1">3.1.1</a>&nbsp;&nbsp;&nbsp;<a href="#data.type">Data Type</a><ul>
     583                     <li><a href="#rfc.section.3.1.1">3.1.1</a>&nbsp;&nbsp;&nbsp;<a href="#data.type">Processing the Data</a><ul>
    584584                           <li><a href="#rfc.section.3.1.1.1">3.1.1.1</a>&nbsp;&nbsp;&nbsp;<a href="#media.type">Media Type</a></li>
    585585                           <li><a href="#rfc.section.3.1.1.2">3.1.1.2</a>&nbsp;&nbsp;&nbsp;<a href="#charset">Charset</a></li>
    … …  
    589589                        </ul>
    590590                     </li>
    591                      <li><a href="#rfc.section.3.1.2">3.1.2</a>&nbsp;&nbsp;&nbsp;<a href="#data.encoding">Data Encoding</a><ul>
     591                     <li><a href="#rfc.section.3.1.2">3.1.2</a>&nbsp;&nbsp;&nbsp;<a href="#data.encoding">Encoding for Compression or Integrity</a><ul>
    592592                           <li><a href="#rfc.section.3.1.2.1">3.1.2.1</a>&nbsp;&nbsp;&nbsp;<a href="#content.codings">Content Codings</a></li>
    593593                           <li><a href="#rfc.section.3.1.2.2">3.1.2.2</a>&nbsp;&nbsp;&nbsp;<a href="#header.content-encoding">Content-Encoding</a></li>
    … …  
    890890         </table>
    891891      </div>
    892       <h3 id="rfc.section.3.1.1"><a href="#rfc.section.3.1.1">3.1.1</a>&nbsp;<a id="data.type" href="#data.type">Data Type</a></h3>
     892      <h3 id="rfc.section.3.1.1"><a href="#rfc.section.3.1.1">3.1.1</a>&nbsp;<a id="data.type" href="#data.type">Processing the Data</a></h3>
    893893      <h4 id="rfc.section.3.1.1.1"><a href="#rfc.section.3.1.1.1">3.1.1.1</a>&nbsp;<a id="media.type" href="#media.type">Media Type</a></h4>
    894       <p id="rfc.section.3.1.1.1.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.2" title="Content-Type">Section&nbsp;3.1.1.5</a>) and <a href="#header.accept" class="smpl">Accept</a> (<a href="#header.accept" id="rfc.xref.header.accept.1" title="Accept">Section&nbsp;6.3.2</a>) header fields in order to provide open and extensible data typing and type negotiation.
     894      <p id="rfc.section.3.1.1.1.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.2" title="Content-Type">Section&nbsp;3.1.1.5</a>) and <a href="#header.accept" class="smpl">Accept</a> (<a href="#header.accept" id="rfc.xref.header.accept.1" title="Accept">Section&nbsp;6.3.2</a>) header fields in order to provide open and extensible data typing and type negotiation. Media types define both a data format
     895         and various processing models: how to process that data in accordance with each context in which it is received.
    895896      </p>
    896897      <div id="rfc.figure.u.1"></div><pre class="inline"><span id="rfc.iref.g.1"></span><span id="rfc.iref.g.2"></span><span id="rfc.iref.g.3"></span>  <a href="#media.type" class="smpl">media-type</a> = <a href="#media.type" class="smpl">type</a> "/" <a href="#media.type" class="smpl">subtype</a> *( <a href="#imported.abnf" class="smpl">OWS</a> ";" <a href="#imported.abnf" class="smpl">OWS</a> <a href="#rule.parameter" class="smpl">parameter</a> )
    … …  
    916917  text/html; charset="utf-8"
    917918</pre><p id="rfc.section.3.1.1.1.p.8">Media-type values are registered with the Internet Assigned Number Authority (IANA). The media type registration process is
    918          outlined in <a href="#RFC4288" id="rfc.xref.RFC4288.1"><cite title="Media Type Specifications and Registration Procedures">[RFC4288]</cite></a>. Use of non-registered media types is discouraged.
     919         outlined in <a href="#BCP13" id="rfc.xref.BCP13.1"><cite title="Media Type Specifications and Registration Procedures">[BCP13]</cite></a>. Use of non-registered media types is discouraged.
    919920      </p>
    920921      <h4 id="rfc.section.3.1.1.2"><a href="#rfc.section.3.1.1.2">3.1.1.2</a>&nbsp;<a id="charset" href="#charset">Charset</a></h4>
    … …  
    970971         sniffing" when it is used.
    971972      </p>
    972       <h3 id="rfc.section.3.1.2"><a href="#rfc.section.3.1.2">3.1.2</a>&nbsp;<a id="data.encoding" href="#data.encoding">Data Encoding</a></h3>
     973      <h3 id="rfc.section.3.1.2"><a href="#rfc.section.3.1.2">3.1.2</a>&nbsp;<a id="data.encoding" href="#data.encoding">Encoding for Compression or Integrity</a></h3>
    973974      <div id="rfc.iref.c.3"></div>
    974975      <div id="rfc.iref.c.4"></div>
    … …  
    34563457      </div>
    34573458      <h2 id="rfc.section.9.3"><a href="#rfc.section.9.3">9.3</a>&nbsp;<a id="header.field.registry" href="#header.field.registry">Header Field Registry</a></h2>
    3458       <p id="rfc.section.9.3.p.1">HTTP header fields are registered within the Message Header Field Registry located at &lt;<a href="http://www.iana.org/assignments/message-headers/message-header-index.html">http://www.iana.org/assignments/message-headers/message-header-index.html</a>&gt;, as defined by <a href="#RFC3864" id="rfc.xref.RFC3864.1"><cite title="Registration Procedures for Message Header Fields">[RFC3864]</cite></a>.
     3459      <p id="rfc.section.9.3.p.1">HTTP header fields are registered within the Message Header Field Registry located at &lt;<a href="http://www.iana.org/assignments/message-headers/message-header-index.html">http://www.iana.org/assignments/message-headers/message-header-index.html</a>&gt;, as defined by <a href="#BCP90" id="rfc.xref.BCP90.1"><cite title="Registration Procedures for Message Header Fields">[BCP90]</cite></a>.
    34593460      </p>
    34603461      <h3 id="rfc.section.9.3.1"><a href="#rfc.section.9.3.1">9.3.1</a>&nbsp;<a id="considerations.for.new.header.fields" href="#considerations.for.new.header.fields">Considerations for New Header Fields</a></h3>
    … …  
    34623463         or the connection (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.Part1.31"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a> for a general definition of header field syntax in HTTP messages.
    34633464      </p>
    3464       <p id="rfc.section.9.3.1.p.2">The requirements for header field names are defined in <a href="http://tools.ietf.org/html/rfc3864#section-4.1">Section 4.1</a> of <a href="#RFC3864" id="rfc.xref.RFC3864.2"><cite title="Registration Procedures for Message Header Fields">[RFC3864]</cite></a>. Authors of specifications defining new fields are advised to keep the name as short as practical, and not to prefix them
     3465      <p id="rfc.section.9.3.1.p.2">The requirements for header field names are defined in <a href="#BCP90" id="rfc.xref.BCP90.2"><cite title="Registration Procedures for Message Header Fields">[BCP90]</cite></a>. Authors of specifications defining new fields are advised to keep the name as short as practical, and not to prefix them
    34653466         with "X-" if they are to be registered (either immediately or in the future).
    34663467      </p>
    … …  
    39083909      <table>                                         
    39093910         <tr>
     3911            <td class="reference"><b id="BCP13">[BCP13]</b></td>
     3912            <td class="top"><a href="mailto:ned.freed@mrochek.com" title="Sun Microsystems">Freed, N.</a> and <a href="mailto:klensin+ietf@jck.com">J. Klensin</a>, “<a href="http://tools.ietf.org/html/rfc4288">Media Type Specifications and Registration Procedures</a>”, BCP&nbsp;13, RFC&nbsp;4288, December&nbsp;2005.
     3913            </td>
     3914         </tr>
     3915         <tr>
     3916            <td class="reference"><b id="BCP90">[BCP90]</b></td>
     3917            <td class="top"><a href="mailto:GK-IETF@ninebynine.org" title="Nine by Nine">Klyne, G.</a>, <a href="mailto:mnot@pobox.com" title="BEA Systems">Nottingham, M.</a>, and <a href="mailto:JeffMogul@acm.org" title="HP Labs">J. Mogul</a>, “<a href="http://tools.ietf.org/html/rfc3864">Registration Procedures for Message Header Fields</a>”, BCP&nbsp;90, RFC&nbsp;3864, September&nbsp;2004.
     3918            </td>
     3919         </tr>
     3920         <tr>
    39103921            <td class="reference"><b id="REST">[REST]</b></td>
    39113922            <td class="top">Fielding, R., “<a href="http://roy.gbiv.com/pubs/dissertation/top.htm">Architectural Styles and the Design of Network-based Software Architectures</a>”, Doctoral Dissertation, University of California, Irvine, September&nbsp;2000, &lt;<a href="http://roy.gbiv.com/pubs/dissertation/top.htm">http://roy.gbiv.com/pubs/dissertation/top.htm</a>&gt;.
    … …  
    39683979         </tr>
    39693980         <tr>
    3970             <td class="reference"><b id="RFC3864">[RFC3864]</b></td>
    3971             <td class="top"><a href="mailto:GK-IETF@ninebynine.org" title="Nine by Nine">Klyne, G.</a>, <a href="mailto:mnot@pobox.com" title="BEA Systems">Nottingham, M.</a>, and <a href="mailto:JeffMogul@acm.org" title="HP Labs">J. Mogul</a>, “<a href="http://tools.ietf.org/html/rfc3864">Registration Procedures for Message Header Fields</a>”, BCP&nbsp;90, RFC&nbsp;3864, September&nbsp;2004.
    3972             </td>
    3973          </tr>
    3974          <tr>
    3975             <td class="reference"><b id="RFC4288">[RFC4288]</b></td>
    3976             <td class="top"><a href="mailto:ned.freed@mrochek.com" title="Sun Microsystems">Freed, N.</a> and <a href="mailto:klensin+ietf@jck.com">J. Klensin</a>, “<a href="http://tools.ietf.org/html/rfc4288">Media Type Specifications and Registration Procedures</a>”, BCP&nbsp;13, RFC&nbsp;4288, December&nbsp;2005.
    3977             </td>
    3978          </tr>
    3979          <tr>
    39803981            <td class="reference"><b id="RFC5226">[RFC5226]</b></td>
    39813982            <td class="top"><a href="mailto:narten@us.ibm.com" title="IBM">Narten, T.</a> and <a href="mailto:Harald@Alvestrand.no" title="Google">H. Alvestrand</a>, “<a href="http://tools.ietf.org/html/rfc5226">Guidelines for Writing an IANA Considerations Section in RFCs</a>”, BCP&nbsp;26, RFC&nbsp;5226, May&nbsp;2008.
    … …  
    40844085      </p>
    40854086      <h1 id="rfc.section.C"><a href="#rfc.section.C">C.</a>&nbsp;<a id="changes.from.rfc.2616" href="#changes.from.rfc.2616">Changes from RFC 2616</a></h1>
    4086       <p id="rfc.section.C.p.1">The term "representation" is introduced, replacing both "entity" and "variant." (<a href="#representations" title="Representations">Section&nbsp;3</a>)
    4087       </p>
    4088       <p id="rfc.section.C.p.2">"Server-Driven" and "agent-driven" content negotiation are now called "proactive" and "reactive" content negotiation (respectively).
     4087      <p id="rfc.section.C.p.1">Request semantics embedded in a URI should be disabled when those semantics are inconsistent with the request method, since
     4088         this is a common cause of interoperability failure.
     4089      </p>
     4090      <p id="rfc.section.C.p.2">The term "representation" is introduced, replacing both "entity" and "variant." (<a href="#representations" title="Representations">Section&nbsp;3</a>)
     4091      </p>
     4092      <p id="rfc.section.C.p.3">Rules for identifying the payload of a message have been defined. (<a href="#identifying.payload" title="Identifying a Representation">Section&nbsp;3.1.4.1</a>)
     4093      </p>
     4094      <p id="rfc.section.C.p.4">"Server-Driven" and "agent-driven" content negotiation are now called "proactive" and "reactive" content negotiation (respectively).
    40894095         (<a href="#content.negotiation" title="Content Negotiation">Section&nbsp;3.4</a>)
    40904096      </p>
    4091       <p id="rfc.section.C.p.3"> <a href="#header.content-location" class="smpl">Content-Location</a> no longer sets a base URI, due to poor implementation support (which was caused by too many broken servers emitting bogus
     4097      <p id="rfc.section.C.p.5"> <a href="#header.content-location" class="smpl">Content-Location</a> no longer sets a base URI, due to poor implementation support (which was caused by too many broken servers emitting bogus
    40924098         Content-Location header fields, and also the potentially undesirable effect of potentially breaking relative links in content-negotiated
    40934099         resources). (<a href="#header.content-location" id="rfc.xref.header.content-location.5" title="Content-Location">Section&nbsp;3.1.4.2</a>)
    40944100      </p>
    4095       <p id="rfc.section.C.p.4">Rules for identifying the payload of a message have been defined. (<a href="#identifying.payload" title="Identifying a Representation">Section&nbsp;3.1.4.1</a>)
    4096       </p>
    4097       <p id="rfc.section.C.p.5">GET requests can have a body; it just has no meaning. (<a href="#GET" id="rfc.xref.GET.4" title="GET">Section&nbsp;5.3.1</a>)
    4098       </p>
    4099       <p id="rfc.section.C.p.6">The definition of POST has been clarified. (<a href="#POST" id="rfc.xref.POST.4" title="POST">Section&nbsp;5.3.3</a>)
    4100       </p>
    4101       <p id="rfc.section.C.p.7">Servers are no longer required to handle all Content-* header fields in requests. (<a href="#PUT" id="rfc.xref.PUT.4" title="PUT">Section&nbsp;5.3.4</a>)
    4102       </p>
    4103       <p id="rfc.section.C.p.8">Use of <a href="p5-range.html#header.content-range" class="smpl">Content-Range</a> is explicitly banned on PUT requests. (<a href="#PUT" id="rfc.xref.PUT.5" title="PUT">Section&nbsp;5.3.4</a>)
    4104       </p>
    4105       <p id="rfc.section.C.p.9">The CONNECT method is now defined by this specification, taking over from <a href="#RFC2817" id="rfc.xref.RFC2817.2"><cite title="Upgrading to TLS Within HTTP/1.1">[RFC2817]</cite></a>. (<a href="#CONNECT" id="rfc.xref.CONNECT.3" title="CONNECT">Section&nbsp;5.3.6</a>)
    4106       </p>
    4107       <p id="rfc.section.C.p.10">The requirements upon and semantics of CONNECT request and response bodies have been clarified. (<a href="#CONNECT" id="rfc.xref.CONNECT.4" title="CONNECT">Section&nbsp;5.3.6</a>)
    4108       </p>
    4109       <p id="rfc.section.C.p.11">The <a href="#OPTIONS" class="smpl">OPTIONS</a> and <a href="#TRACE" class="smpl">TRACE</a> request methods are now defined as being safe. (<a href="#OPTIONS" id="rfc.xref.OPTIONS.4" title="OPTIONS">Section&nbsp;5.3.7</a> and <a href="#TRACE" id="rfc.xref.TRACE.5" title="TRACE">Section&nbsp;5.3.8</a>)
    4110       </p>
    4111       <p id="rfc.section.C.p.12">The <a href="#header.max-forwards" class="smpl">Max-Forwards</a> header field is now restricted to the OPTIONS and TRACE methods (previously, extension methods could have used it as well).
     4101      <p id="rfc.section.C.p.6">GET requests can have a body; it just has no meaning. (<a href="#GET" id="rfc.xref.GET.4" title="GET">Section&nbsp;5.3.1</a>)
     4102      </p>
     4103      <p id="rfc.section.C.p.7">The definition of POST has been clarified. (<a href="#POST" id="rfc.xref.POST.4" title="POST">Section&nbsp;5.3.3</a>)
     4104      </p>
     4105      <p id="rfc.section.C.p.8">Servers are no longer required to handle all Content-* header fields in requests. (<a href="#PUT" id="rfc.xref.PUT.4" title="PUT">Section&nbsp;5.3.4</a>)
     4106      </p>
     4107      <p id="rfc.section.C.p.9">Use of <a href="p5-range.html#header.content-range" class="smpl">Content-Range</a> is explicitly banned on PUT requests. (<a href="#PUT" id="rfc.xref.PUT.5" title="PUT">Section&nbsp;5.3.4</a>)
     4108      </p>
     4109      <p id="rfc.section.C.p.10">The CONNECT method is now defined by this specification, taking over from <a href="#RFC2817" id="rfc.xref.RFC2817.2"><cite title="Upgrading to TLS Within HTTP/1.1">[RFC2817]</cite></a>. (<a href="#CONNECT" id="rfc.xref.CONNECT.3" title="CONNECT">Section&nbsp;5.3.6</a>)
     4110      </p>
     4111      <p id="rfc.section.C.p.11">The requirements upon and semantics of CONNECT request and response bodies have been clarified. (<a href="#CONNECT" id="rfc.xref.CONNECT.4" title="CONNECT">Section&nbsp;5.3.6</a>)
     4112      </p>
     4113      <p id="rfc.section.C.p.12">The <a href="#OPTIONS" class="smpl">OPTIONS</a> and <a href="#TRACE" class="smpl">TRACE</a> request methods are now defined as being safe. (<a href="#OPTIONS" id="rfc.xref.OPTIONS.4" title="OPTIONS">Section&nbsp;5.3.7</a> and <a href="#TRACE" id="rfc.xref.TRACE.5" title="TRACE">Section&nbsp;5.3.8</a>)
     4114      </p>
     4115      <p id="rfc.section.C.p.13">The <a href="#header.max-forwards" class="smpl">Max-Forwards</a> header field is now restricted to the OPTIONS and TRACE methods (previously, extension methods could have used it as well).
    41124116         (<a href="#header.max-forwards" id="rfc.xref.header.max-forwards.5" title="Max-Forwards">Section&nbsp;6.1.1</a>)
    41134117      </p>
    4114       <p id="rfc.section.C.p.13">The ABNF for the "<a href="#header.expect" class="smpl">Expect</a>" header field has been both fixed (allowing parameters for value-less expectations as well) and simplified (allowing trailing
     4118      <p id="rfc.section.C.p.14">The ABNF for the "<a href="#header.expect" class="smpl">Expect</a>" header field has been both fixed (allowing parameters for value-less expectations as well) and simplified (allowing trailing
    41154119         semicolons after "100-continue" when they were invalid before). (<a href="#header.expect" id="rfc.xref.header.expect.4" title="Expect">Section&nbsp;6.1.2</a>)
    41164120      </p>
    4117       <p id="rfc.section.C.p.14">Special casing for ISO-8859-1 in <a href="#header.accept-charset" class="smpl">Accept-Charset</a> has been removed. (<a href="#header.accept-charset" id="rfc.xref.header.accept-charset.4" title="Accept-Charset">Section&nbsp;6.3.3</a>)
    4118       </p>
    4119       <p id="rfc.section.C.p.15">Requirements for sending the Date header field have been clarified. (<a href="#header.date" id="rfc.xref.header.date.4" title="Date">Section&nbsp;8.1.1.2</a>)
    4120       </p>
    4121       <p id="rfc.section.C.p.16">The <a href="#header.referer" class="smpl">Referer</a> header field can now have a value of "about:blank" as an alternative to not sending a Referer header field. (<a href="#header.referer" id="rfc.xref.header.referer.3" title="Referer">Section&nbsp;6.5.2</a>)
    4122       </p>
    4123       <p id="rfc.section.C.p.17">The <a href="#status.201" class="smpl">201 (Created)</a> status code can indicate that more than one resource has been created (as well as just one).
    4124       </p>
    4125       <p id="rfc.section.C.p.18">The definition of <a href="#status.203" class="smpl">203 (Non-Authoritative Information)</a> has been broadened to include cases of payload transformations as well. (<a href="#status.203" id="rfc.xref.status.203.3" title="203 Non-Authoritative Information">Section&nbsp;7.3.4</a>)
    4126       </p>
    4127       <p id="rfc.section.C.p.19">Redirect status codes <a href="#status.301" class="smpl">301</a>, <a href="#status.302" class="smpl">302</a>, and <a href="#status.307" class="smpl">307</a> no longer have normative requirements on response payloads and user interaction. (<a href="#status.3xx" id="rfc.xref.status.3xx.1" title="Redirection 3xx">Section&nbsp;7.4</a>)
    4128       </p>
    4129       <p id="rfc.section.C.p.20">The request methods that are safe to automatically redirect is no longer a closed set; user agents are able to make that determination
     4121      <p id="rfc.section.C.p.15">Special casing for ISO-8859-1 in <a href="#header.accept-charset" class="smpl">Accept-Charset</a> has been removed. (<a href="#header.accept-charset" id="rfc.xref.header.accept-charset.4" title="Accept-Charset">Section&nbsp;6.3.3</a>)
     4122      </p>
     4123      <p id="rfc.section.C.p.16">Requirements for sending the Date header field have been clarified. (<a href="#header.date" id="rfc.xref.header.date.4" title="Date">Section&nbsp;8.1.1.2</a>)
     4124      </p>
     4125      <p id="rfc.section.C.p.17">The <a href="#header.referer" class="smpl">Referer</a> header field can now have a value of "about:blank" as an alternative to not sending a Referer header field. (<a href="#header.referer" id="rfc.xref.header.referer.3" title="Referer">Section&nbsp;6.5.2</a>)
     4126      </p>
     4127      <p id="rfc.section.C.p.18">The <a href="#status.201" class="smpl">201 (Created)</a> status code can indicate that more than one resource has been created (as well as just one).
     4128      </p>
     4129      <p id="rfc.section.C.p.19">The definition of <a href="#status.203" class="smpl">203 (Non-Authoritative Information)</a> has been broadened to include cases of payload transformations as well. (<a href="#status.203" id="rfc.xref.status.203.3" title="203 Non-Authoritative Information">Section&nbsp;7.3.4</a>)
     4130      </p>
     4131      <p id="rfc.section.C.p.20">Redirect status codes <a href="#status.301" class="smpl">301</a>, <a href="#status.302" class="smpl">302</a>, and <a href="#status.307" class="smpl">307</a> no longer have normative requirements on response payloads and user interaction. (<a href="#status.3xx" id="rfc.xref.status.3xx.1" title="Redirection 3xx">Section&nbsp;7.4</a>)
     4132      </p>
     4133      <p id="rfc.section.C.p.21">The request methods that are safe to automatically redirect is no longer a closed set; user agents are able to make that determination
    41304134         based upon the request method semantics. (<a href="#status.3xx" id="rfc.xref.status.3xx.2" title="Redirection 3xx">Section&nbsp;7.4</a>)
    41314135      </p>
    4132       <p id="rfc.section.C.p.21">The syntax of the <a href="#header.location" class="smpl">Location</a> header field has been corrected to allow URI references (including relative references and fragments), along with some clarifications
     4136      <p id="rfc.section.C.p.22">The syntax of the <a href="#header.location" class="smpl">Location</a> header field has been corrected to allow URI references (including relative references and fragments), along with some clarifications
    41334137         as to when use of fragments would not be appropriate. (<a href="#header.location" id="rfc.xref.header.location.5" title="Location">Section&nbsp;8.1.2</a>)
    41344138      </p>
    4135       <p id="rfc.section.C.p.22">The 303 (See Other) status code is now cacheable, if explicit freshness information is available. (<a href="#status.303" id="rfc.xref.status.303.3" title="303 See Other">Section&nbsp;7.4.4</a>)
    4136       </p>
    4137       <p id="rfc.section.C.p.23">User agents are now allowed to rewrite the method from POST to GET for status codes <a href="#status.301" class="smpl">301</a> and <a href="#status.302" class="smpl">302</a>. (Sections <a href="#status.301" id="rfc.xref.status.301.3" title="301 Moved Permanently">7.4.2</a>, <a href="#status.302" id="rfc.xref.status.302.3" title="302 Found">7.4.3</a> and <a href="#status.307" id="rfc.xref.status.307.3" title="307 Temporary Redirect">7.4.7</a>)
    4138       </p>
    4139       <p id="rfc.section.C.p.24">The <a href="#status.305" class="smpl">305 (Use Proxy)</a> status code is now deprecated, because user agents did not implement it. It used to indicate that the target resource needed
     4139      <p id="rfc.section.C.p.23">The 303 (See Other) status code is now cacheable, if explicit freshness information is available. (<a href="#status.303" id="rfc.xref.status.303.3" title="303 See Other">Section&nbsp;7.4.4</a>)
     4140      </p>
     4141      <p id="rfc.section.C.p.24">User agents are now allowed to rewrite the method from POST to GET for status codes <a href="#status.301" class="smpl">301</a> and <a href="#status.302" class="smpl">302</a>. (Sections <a href="#status.301" id="rfc.xref.status.301.3" title="301 Moved Permanently">7.4.2</a>, <a href="#status.302" id="rfc.xref.status.302.3" title="302 Found">7.4.3</a> and <a href="#status.307" id="rfc.xref.status.307.3" title="307 Temporary Redirect">7.4.7</a>)
     4142      </p>
     4143      <p id="rfc.section.C.p.25">The <a href="#status.305" class="smpl">305 (Use Proxy)</a> status code is now deprecated, because user agents did not implement it. It used to indicate that the target resource needed
    41404144         to be accessed through the proxy given by the <a href="#header.location" class="smpl">Location</a> field. The recipient was expected to repeat this single request via the proxy. (<a href="#status.305" id="rfc.xref.status.305.3" title="305 Use Proxy">Section&nbsp;7.4.5</a>)
    41414145      </p>
    4142       <p id="rfc.section.C.p.25">The <a href="#status.400" class="smpl">400 (Bad Request)</a> status code has been made more generic; it isn't limited to syntax errors. (<a href="#status.400" id="rfc.xref.status.400.3" title="400 Bad Request">Section&nbsp;7.5.1</a>)
    4143       </p>
    4144       <p id="rfc.section.C.p.26">The <a href="#status.403" class="smpl">403 (Forbidden)</a> status code has been clarified, especially with regards to authentication. (<a href="#status.403" id="rfc.xref.status.403.3" title="403 Forbidden">Section&nbsp;7.5.3</a>)
    4145       </p>
    4146       <p id="rfc.section.C.p.27">The <a href="#status.426" class="smpl">426 (Upgrade Required)</a> status code has been incorporated from <a href="#RFC2817" id="rfc.xref.RFC2817.3"><cite title="Upgrading to TLS Within HTTP/1.1">[RFC2817]</cite></a>. (<a href="#status.426" id="rfc.xref.status.426.3" title="426 Upgrade Required">Section&nbsp;7.5.15</a>)
    4147       </p>
    4148       <p id="rfc.section.C.p.28"> <a href="#header.allow" class="smpl">Allow</a> has been reclassified as a response header field, removing the option to specify it in a PUT request. (<a href="#header.allow" id="rfc.xref.header.allow.4" title="Allow">Section&nbsp;8.4.1</a>)
    4149       </p>
    4150       <p id="rfc.section.C.p.29">Requirements relating to the content of the Allow header have been relaxed; correspondingly, clients are not required to always
     4146      <p id="rfc.section.C.p.26">The <a href="#status.400" class="smpl">400 (Bad Request)</a> status code has been made more generic; it isn't limited to syntax errors. (<a href="#status.400" id="rfc.xref.status.400.3" title="400 Bad Request">Section&nbsp;7.5.1</a>)
     4147      </p>
     4148      <p id="rfc.section.C.p.27">The <a href="#status.403" class="smpl">403 (Forbidden)</a> status code has been clarified, especially with regards to authentication. (<a href="#status.403" id="rfc.xref.status.403.3" title="403 Forbidden">Section&nbsp;7.5.3</a>)
     4149      </p>
     4150      <p id="rfc.section.C.p.28">The <a href="#status.426" class="smpl">426 (Upgrade Required)</a> status code has been incorporated from <a href="#RFC2817" id="rfc.xref.RFC2817.3"><cite title="Upgrading to TLS Within HTTP/1.1">[RFC2817]</cite></a>. (<a href="#status.426" id="rfc.xref.status.426.3" title="426 Upgrade Required">Section&nbsp;7.5.15</a>)
     4151      </p>
     4152      <p id="rfc.section.C.p.29"> <a href="#header.allow" class="smpl">Allow</a> has been reclassified as a response header field, removing the option to specify it in a PUT request. (<a href="#header.allow" id="rfc.xref.header.allow.4" title="Allow">Section&nbsp;8.4.1</a>)
     4153      </p>
     4154      <p id="rfc.section.C.p.30">Requirements relating to the content of the Allow header have been relaxed; correspondingly, clients are not required to always
    41514155         trust its value. (<a href="#header.allow" id="rfc.xref.header.allow.5" title="Allow">Section&nbsp;8.4.1</a>)
    41524156      </p>
    4153       <p id="rfc.section.C.p.30">The requirement to generate a <a href="p1-messaging.html#header.via" class="smpl">Via</a> header field has been moved from the description of the <a href="#header.server" class="smpl">Server</a> header field to <a href="p1-messaging.html#header.via" title="Via">Section 5.7.1</a> of <a href="#Part1" id="rfc.xref.Part1.44"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>. (<a href="#header.server" id="rfc.xref.header.server.4" title="Server">Section&nbsp;8.4.2</a>)
    4154       </p>
    4155       <p id="rfc.section.C.p.31">The contexts that charset is used in have been clarified. (<a href="#charset" title="Charset">Section&nbsp;3.1.1.2</a>)
    4156       </p>
    4157       <p id="rfc.section.C.p.32">The default charset of "ISO-8859-1" for text media types has been removed; the default now is whatever the media type definition
     4157      <p id="rfc.section.C.p.31">The requirement to generate a <a href="p1-messaging.html#header.via" class="smpl">Via</a> header field has been moved from the description of the <a href="#header.server" class="smpl">Server</a> header field to <a href="p1-messaging.html#header.via" title="Via">Section 5.7.1</a> of <a href="#Part1" id="rfc.xref.Part1.44"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>. (<a href="#header.server" id="rfc.xref.header.server.4" title="Server">Section&nbsp;8.4.2</a>)
     4158      </p>
     4159      <p id="rfc.section.C.p.32">The contexts that charset is used in have been clarified. (<a href="#charset" title="Charset">Section&nbsp;3.1.1.2</a>)
     4160      </p>
     4161      <p id="rfc.section.C.p.33">The default charset of "ISO-8859-1" for text media types has been removed; the default now is whatever the media type definition
    41584162         says. (<a href="#canonicalization.and.text.defaults" title="Canonicalization and Text Defaults">Section&nbsp;3.1.1.3</a>)
    41594163      </p>
    4160       <p id="rfc.section.C.p.33">Registration of Content Codings now requires IETF Review. (<a href="#content.coding.registry" title="Content Coding Registry">Section&nbsp;9.4</a>)
    4161       </p>
    4162       <p id="rfc.section.C.p.34">The Content-MD5 header field has been removed, because it was inconsistently implemented with respect to partial responses,
     4164      <p id="rfc.section.C.p.34">Registration of Content Codings now requires IETF Review. (<a href="#content.coding.registry" title="Content Coding Registry">Section&nbsp;9.4</a>)
     4165      </p>
     4166      <p id="rfc.section.C.p.35">The Content-MD5 header field has been removed, because it was inconsistently implemented with respect to partial responses,
    41634167         and also because of known deficiencies in the hash algorithm itself (see <a href="#RFC6151" id="rfc.xref.RFC6151.1"><cite title="Updated Security Considerations for the MD5 Message-Digest and the HMAC-MD5 Algorithms">[RFC6151]</cite></a> for details).
    41644168      </p>
    4165       <p id="rfc.section.C.p.35">This specification introduces a Method Registry. (<a href="#method.registry" title="Method Registry">Section&nbsp;9.1</a>)
    4166       </p>
    4167       <p id="rfc.section.C.p.36">The Status Code Registry is now defined by this specification; previously, it was defined in <a href="http://tools.ietf.org/html/rfc2817#section-7.1">Section 7.1</a> of <a href="#RFC2817" id="rfc.xref.RFC2817.4"><cite title="Upgrading to TLS Within HTTP/1.1">[RFC2817]</cite></a>. (<a href="#status.code.registry" title="Status Code Registry">Section&nbsp;9.2</a>)
    4168       </p>
    4169       <p id="rfc.section.C.p.37">References to the "identity" transfer coding token have been removed. (<a href="#no.content-transfer-encoding" id="rfc.xref.no.content-transfer-encoding.1" title="No Content-Transfer-Encoding">Appendix&nbsp;A.5</a>)
    4170       </p>
    4171       <p id="rfc.section.C.p.38">The Content-Disposition header field is now defined by <a href="#RFC6266" id="rfc.xref.RFC6266.2"><cite title="Use of the Content-Disposition Header Field in the Hypertext Transfer Protocol (HTTP)">[RFC6266]</cite></a>. (<a href="#additional.features" title="Additional Features">Appendix&nbsp;B</a>)
     4169      <p id="rfc.section.C.p.36">This specification introduces a Method Registry. (<a href="#method.registry" title="Method Registry">Section&nbsp;9.1</a>)
     4170      </p>
     4171      <p id="rfc.section.C.p.37">The Status Code Registry is now defined by this specification; previously, it was defined in <a href="http://tools.ietf.org/html/rfc2817#section-7.1">Section 7.1</a> of <a href="#RFC2817" id="rfc.xref.RFC2817.4"><cite title="Upgrading to TLS Within HTTP/1.1">[RFC2817]</cite></a>. (<a href="#status.code.registry" title="Status Code Registry">Section&nbsp;9.2</a>)
     4172      </p>
     4173      <p id="rfc.section.C.p.38">References to the "identity" transfer coding token have been removed. (<a href="#no.content-transfer-encoding" id="rfc.xref.no.content-transfer-encoding.1" title="No Content-Transfer-Encoding">Appendix&nbsp;A.5</a>)
     4174      </p>
     4175      <p id="rfc.section.C.p.39">The Content-Disposition header field is now defined by <a href="#RFC6266" id="rfc.xref.RFC6266.2"><cite title="Use of the Content-Disposition Header Field in the Hypertext Transfer Protocol (HTTP)">[RFC6266]</cite></a>. (<a href="#additional.features" title="Additional Features">Appendix&nbsp;B</a>)
    41724176      </p>
    41734177      <h1 id="rfc.section.D"><a href="#rfc.section.D">D.</a>&nbsp;<a id="imported.abnf" href="#imported.abnf">Imported ABNF</a></h1>
    … …  
    43434347      </ul>
    43444348      <h1 id="rfc.index"><a href="#rfc.index">Index</a></h1>
    4345       <p class="noprint"><a href="#rfc.index.1">1</a> <a href="#rfc.index.2">2</a> <a href="#rfc.index.3">3</a> <a href="#rfc.index.4">4</a> <a href="#rfc.index.5">5</a> <a href="#rfc.index.A">A</a> <a href="#rfc.index.C">C</a> <a href="#rfc.index.D">D</a> <a href="#rfc.index.E">E</a> <a href="#rfc.index.F">F</a> <a href="#rfc.index.G">G</a> <a href="#rfc.index.H">H</a> <a href="#rfc.index.I">I</a> <a href="#rfc.index.L">L</a> <a href="#rfc.index.M">M</a> <a href="#rfc.index.O">O</a> <a href="#rfc.index.P">P</a> <a href="#rfc.index.R">R</a> <a href="#rfc.index.S">S</a> <a href="#rfc.index.T">T</a> <a href="#rfc.index.U">U</a> <a href="#rfc.index.V">V</a> <a href="#rfc.index.X">X</a>
     4349      <p class="noprint"><a href="#rfc.index.1">1</a> <a href="#rfc.index.2">2</a> <a href="#rfc.index.3">3</a> <a href="#rfc.index.4">4</a> <a href="#rfc.index.5">5</a> <a href="#rfc.index.A">A</a> <a href="#rfc.index.B">B</a> <a href="#rfc.index.C">C</a> <a href="#rfc.index.D">D</a> <a href="#rfc.index.E">E</a> <a href="#rfc.index.F">F</a> <a href="#rfc.index.G">G</a> <a href="#rfc.index.H">H</a> <a href="#rfc.index.I">I</a> <a href="#rfc.index.L">L</a> <a href="#rfc.index.M">M</a> <a href="#rfc.index.O">O</a> <a href="#rfc.index.P">P</a> <a href="#rfc.index.R">R</a> <a href="#rfc.index.S">S</a> <a href="#rfc.index.T">T</a> <a href="#rfc.index.U">U</a> <a href="#rfc.index.V">V</a> <a href="#rfc.index.X">X</a>
    43464350      </p>
    43474351      <div class="print2col">
    … …  
    44104414                  <li>Accept-Language header field&nbsp;&nbsp;<a href="#rfc.xref.header.accept-language.1">3.4.1</a>, <a href="#rfc.xref.header.accept-language.2">6.3</a>, <a href="#rfc.iref.a.4"><b>6.3.5</b></a>, <a href="#rfc.xref.header.accept-language.3">9.3.2</a></li>
    44114415                  <li>Allow header field&nbsp;&nbsp;<a href="#rfc.xref.header.allow.1">5.1</a>, <a href="#rfc.xref.header.allow.2">8.4</a>, <a href="#rfc.iref.a.5"><b>8.4.1</b></a>, <a href="#rfc.xref.header.allow.3">9.3.2</a>, <a href="#rfc.xref.header.allow.4">C</a>, <a href="#rfc.xref.header.allow.5">C</a></li>
     4416               </ul>
     4417            </li>
     4418            <li><a id="rfc.index.B" href="#rfc.index.B"><b>B</b></a><ul>
     4419                  <li><em>BCP13</em>&nbsp;&nbsp;<a href="#rfc.xref.BCP13.1">3.1.1.1</a>, <a href="#BCP13"><b>12.2</b></a></li>
     4420                  <li><em>BCP90</em>&nbsp;&nbsp;<a href="#rfc.xref.BCP90.1">9.3</a>, <a href="#rfc.xref.BCP90.2">9.3.1</a>, <a href="#BCP90"><b>12.2</b></a></li>
    44124421               </ul>
    44134422            </li>
    … …  
    46624671                  </li>
    46634672                  <li><em>RFC2978</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2978.1">3.1.1.2</a>, <a href="#RFC2978"><b>12.2</b></a></li>
    4664                   <li><em>RFC3864</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3864.1">9.3</a>, <a href="#rfc.xref.RFC3864.2">9.3.1</a>, <a href="#RFC3864"><b>12.2</b></a><ul>
    4665                         <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3864.2">9.3.1</a></li>
    4666                      </ul>
    4667                   </li>
    46684673                  <li><em>RFC3986</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.1">8.1.2</a>, <a href="#rfc.xref.RFC3986.2">8.1.2</a>, <a href="#RFC3986"><b>12.1</b></a><ul>
    46694674                        <li><em>Section 4.2</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.1">8.1.2</a></li>
    … …  
    46714676                     </ul>
    46724677                  </li>
    4673                   <li><em>RFC4288</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4288.1">3.1.1.1</a>, <a href="#RFC4288"><b>12.2</b></a></li>
    46744678                  <li><em>RFC4647</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4647.1">6.3.5</a>, <a href="#rfc.xref.RFC4647.2">6.3.5</a>, <a href="#rfc.xref.RFC4647.3">6.3.5</a>, <a href="#rfc.xref.RFC4647.4">6.3.5</a>, <a href="#RFC4647"><b>12.1</b></a><ul>
    46754679                        <li><em>Section 2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4647.1">6.3.5</a></li>
Note: See TracChangeset for help on using the changeset viewer.