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6      <title>Use of the Content-Disposition&nbsp;Header&nbsp;Field
7         in the Hypertext&nbsp;Transfer&nbsp;Protocol&nbsp;(HTTP)
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370       content: "Reschke";
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391</style><link rel="Contents" href="#rfc.toc">
392      <link rel="Author" href="#rfc.authors">
393      <link rel="Copyright" href="#rfc.copyrightnotice">
394      <link rel="Index" href="#rfc.index">
395      <link rel="Chapter" title="1 Introduction" href="#rfc.section.1">
396      <link rel="Chapter" title="2 Notational Conventions" href="#rfc.section.2">
397      <link rel="Chapter" title="3 Header Field Definition" href="#rfc.section.3">
398      <link rel="Chapter" title="4 Examples" href="#rfc.section.4">
399      <link rel="Chapter" title="5 Internationalization Considerations" href="#rfc.section.5">
400      <link rel="Chapter" title="6 Security Considerations" href="#rfc.section.6">
401      <link rel="Chapter" title="7 IANA Considerations" href="#rfc.section.7">
402      <link rel="Chapter" title="8 Acknowledgements" href="#rfc.section.8">
403      <link rel="Chapter" href="#rfc.section.9" title="9 References">
404      <link rel="Appendix" title="A Changes from the RFC 2616 Definition" href="#rfc.section.A">
405      <link rel="Appendix" title="B Differences compared to RFC 2183" href="#rfc.section.B">
406      <link rel="Appendix" title="C Alternative Approaches to Internationalization" href="#rfc.section.C">
407      <link rel="Appendix" title="D Change Log (to be removed by RFC Editor before publication)" href="#rfc.section.D">
408      <meta name="generator" content="http://greenbytes.de/tech/webdav/rfc2629.xslt, Revision 1.640, 2014/06/13 12:42:58, XSLT vendor: SAXON 8.9 from Saxonica http://www.saxonica.com/">
409      <link rel="schema.dct" href="http://purl.org/dc/terms/">
410      <meta name="dct.creator" content="Reschke, J. F.">
411      <meta name="dct.identifier" content="urn:ietf:id:draft-ietf-httpbis-content-disp-00">
412      <meta name="dct.issued" scheme="ISO8601" content="2010-09-03">
413      <meta name="dct.abstract" content="HTTP/1.1 defines the Content-Disposition response header field, but points out that it is not part of the HTTP/1.1 Standard. This specification takes over the definition and registration of Content-Disposition, as used in HTTP, and clarifies internationalization aspects.">
414      <meta name="description" content="HTTP/1.1 defines the Content-Disposition response header field, but points out that it is not part of the HTTP/1.1 Standard. This specification takes over the definition and registration of Content-Disposition, as used in HTTP, and clarifies internationalization aspects.">
415   </head>
416   <body>
417      <table class="header">
418         <tbody>
419            <tr>
420               <td class="left">HTTPbis Working Group</td>
421               <td class="right">J. Reschke</td>
422            </tr>
423            <tr>
424               <td class="left">Internet-Draft</td>
425               <td class="right">greenbytes</td>
426            </tr>
427            <tr>
428               <td class="left">Updates: <a href="https://tools.ietf.org/html/rfc2616">2616</a> (if approved)
429               </td>
430               <td class="right">September 3, 2010</td>
431            </tr>
432            <tr>
433               <td class="left">Intended status: Standards Track</td>
434               <td class="right"></td>
435            </tr>
436            <tr>
437               <td class="left">Expires: March 7, 2011</td>
438               <td class="right"></td>
439            </tr>
440         </tbody>
441      </table>
442      <p class="title">Use of the Content-Disposition&nbsp;Header&nbsp;Field in the Hypertext&nbsp;Transfer&nbsp;Protocol&nbsp;(HTTP)<br><span class="filename">draft-ietf-httpbis-content-disp-00</span></p>
443      <h1 id="rfc.abstract"><a href="#rfc.abstract">Abstract</a></h1>
444      <p>HTTP/1.1 defines the Content-Disposition response header field, but points out that it is not part of the HTTP/1.1 Standard.
445         This specification takes over the definition and registration of Content-Disposition, as used in HTTP, and clarifies internationalization
446         aspects.
447      </p>
448      <h1 id="rfc.note.1"><a href="#rfc.note.1">Editorial Note (To be removed by RFC Editor before publication)</a></h1>
449      <p>This specification is expected to replace the definition of Content-Disposition in the HTTP/1.1 specification, as currently
450         revised by the IETF HTTPbis working group. See also &lt;<a href="http://www3.tools.ietf.org/wg/httpbis/trac/ticket/123">http://www3.tools.ietf.org/wg/httpbis/trac/ticket/123</a>&gt;.
451      </p>
452      <p>Discussion of this draft should take place on the HTTPBIS working group mailing list (ietf-http-wg@w3.org). The current issues
453         list is at &lt;<a href="http://trac.tools.ietf.org/wg/httpbis/trac/query?component=content-disp">http://trac.tools.ietf.org/wg/httpbis/trac/query?component=content-disp</a>&gt; and related documents (including fancy diffs) can be found at &lt;<a href="http://tools.ietf.org/wg/httpbis/">http://tools.ietf.org/wg/httpbis/</a>&gt;.
454      </p>
455      <div id="rfc.status">
456         <h1><a href="#rfc.status">Status of This Memo</a></h1>
457         <p>This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.</p>
458         <p>Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute
459            working documents as Internet-Drafts. The list of current Internet-Drafts is at <a href="http://datatracker.ietf.org/drafts/current/">http://datatracker.ietf.org/drafts/current/</a>.
460         </p>
461         <p>Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other
462            documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as “work
463            in progress”.
464         </p>
465         <p>This Internet-Draft will expire on March 7, 2011.</p>
466      </div>
467      <div id="rfc.copyrightnotice">
468         <h1><a href="#rfc.copyrightnotice">Copyright Notice</a></h1>
469         <p>Copyright © 2010 IETF Trust and the persons identified as the document authors. All rights reserved.</p>
470         <p>This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (<a href="http://trustee.ietf.org/license-info">http://trustee.ietf.org/license-info</a>) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights
471            and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License
472            text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified
473            BSD License.
474         </p>
475      </div>
476      <hr class="noprint">
477      <h1 class="np" id="rfc.toc"><a href="#rfc.toc">Table of Contents</a></h1>
478      <ul class="toc">
479         <li><a href="#rfc.section.1">1.</a>&nbsp;&nbsp;&nbsp;<a href="#introduction">Introduction</a></li>
480         <li><a href="#rfc.section.2">2.</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.2">Notational Conventions</a></li>
481         <li><a href="#rfc.section.3">3.</a>&nbsp;&nbsp;&nbsp;<a href="#header.field.definition">Header Field Definition</a><ul>
482               <li><a href="#rfc.section.3.1">3.1</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.3.1">Grammar</a></li>
483               <li><a href="#rfc.section.3.2">3.2</a>&nbsp;&nbsp;&nbsp;<a href="#disposition.type">Disposition Type</a></li>
484               <li><a href="#rfc.section.3.3">3.3</a>&nbsp;&nbsp;&nbsp;<a href="#disposition.parameter.filename">Disposition Parameter: 'Filename'</a></li>
485               <li><a href="#rfc.section.3.4">3.4</a>&nbsp;&nbsp;&nbsp;<a href="#disposition.parameter.extensionsS">Disposition Parameter: Extensions</a></li>
486               <li><a href="#rfc.section.3.5">3.5</a>&nbsp;&nbsp;&nbsp;<a href="#extensibility">Extensibility</a></li>
487            </ul>
488         </li>
489         <li><a href="#rfc.section.4">4.</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.4">Examples</a></li>
490         <li><a href="#rfc.section.5">5.</a>&nbsp;&nbsp;&nbsp;<a href="#i18n">Internationalization Considerations</a></li>
491         <li><a href="#rfc.section.6">6.</a>&nbsp;&nbsp;&nbsp;<a href="#security.considerations">Security Considerations</a></li>
492         <li><a href="#rfc.section.7">7.</a>&nbsp;&nbsp;&nbsp;<a href="#iana.considerations">IANA Considerations</a><ul>
493               <li><a href="#rfc.section.7.1">7.1</a>&nbsp;&nbsp;&nbsp;<a href="#registry">Registry for Disposition Values and Parameter</a></li>
494               <li><a href="#rfc.section.7.2">7.2</a>&nbsp;&nbsp;&nbsp;<a href="#header.field.registration">Header Field Registration</a></li>
495            </ul>
496         </li>
497         <li><a href="#rfc.section.8">8.</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.8">Acknowledgements</a></li>
498         <li><a href="#rfc.section.9">9.</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references">References</a><ul>
499               <li><a href="#rfc.section.9.1">9.1</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references.1">Normative References</a></li>
500               <li><a href="#rfc.section.9.2">9.2</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references.2">Informative References</a></li>
501            </ul>
502         </li>
503         <li><a href="#rfc.section.A">A.</a>&nbsp;&nbsp;&nbsp;<a href="#changes.from.rfc2616">Changes from the RFC 2616 Definition</a></li>
504         <li><a href="#rfc.section.B">B.</a>&nbsp;&nbsp;&nbsp;<a href="#diffs.compared.to.rfc2183">Differences compared to RFC 2183</a></li>
505         <li><a href="#rfc.section.C">C.</a>&nbsp;&nbsp;&nbsp;<a href="#alternatives">Alternative Approaches to Internationalization</a><ul>
506               <li><a href="#rfc.section.C.1">C.1</a>&nbsp;&nbsp;&nbsp;<a href="#alternatives.rfc2047">RFC 2047 Encoding</a></li>
507               <li><a href="#rfc.section.C.2">C.2</a>&nbsp;&nbsp;&nbsp;<a href="#alternatives.percent">Percent Encoding</a></li>
508               <li><a href="#rfc.section.C.3">C.3</a>&nbsp;&nbsp;&nbsp;<a href="#alternatives.sniff">Encoding Sniffing</a></li>
509               <li><a href="#rfc.section.C.4">C.4</a>&nbsp;&nbsp;&nbsp;<a href="#alternatives.implementations">Implementations</a></li>
510            </ul>
511         </li>
512         <li><a href="#rfc.section.D">D.</a>&nbsp;&nbsp;&nbsp;<a href="#change.log">Change Log (to be removed by RFC Editor before publication)</a><ul>
513               <li><a href="#rfc.section.D.1">D.1</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.D.1">Since draft-reschke-rfc2183-in-http-00</a></li>
514               <li><a href="#rfc.section.D.2">D.2</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.D.2">Since draft-reschke-rfc2183-in-http-01</a></li>
515               <li><a href="#rfc.section.D.3">D.3</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.D.3">Since draft-reschke-rfc2183-in-http-02</a></li>
516               <li><a href="#rfc.section.D.4">D.4</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.D.4">Since draft-reschke-rfc2183-in-http-03</a></li>
517            </ul>
518         </li>
519         <li><a href="#rfc.index">Index</a></li>
520         <li><a href="#rfc.authors">Author's Address</a></li>
521      </ul>
522      <div id="introduction">
523         <h1 id="rfc.section.1" class="np"><a href="#rfc.section.1">1.</a>&nbsp;<a href="#introduction">Introduction</a></h1>
524         <p id="rfc.section.1.p.1">HTTP/1.1 defines the Content-Disposition response header field in <a href="https://tools.ietf.org/html/rfc2616#section-19.5.1">Section 19.5.1</a> of <a href="#RFC2616" id="rfc.xref.RFC2616.1"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>, but points out that it is not part of the HTTP/1.1 Standard (<a href="https://tools.ietf.org/html/rfc2616#section-15.5" id="rfc.xref.RFC2616.2">Section 15.5</a>):
525         </p>
526         <blockquote id="rfc.section.1.p.2" cite="http://tools.ietf.org/html/rfc2616#section-15.5">
527            <p>Content-Disposition is not part of the HTTP standard, but since it is widely implemented, we are documenting its use and risks
528               for implementers.
529            </p>
530         </blockquote>
531         <p id="rfc.section.1.p.3">This specification takes over the definition and registration of Content-Disposition, as used in HTTP. Based on interoperability
532            testing with existing User Agents, it fully defines a profile of the features defined in the Multipurpose Internet Mail Extensions
533            (MIME) variant (<a href="#RFC2183" id="rfc.xref.RFC2183.1"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a>) of the header field, and also clarifies internationalization aspects.
534         </p>
535      </div>
536      <div>
537         <h1 id="rfc.section.2"><a href="#rfc.section.2">2.</a>&nbsp;Notational Conventions
538         </h1>
539         <p id="rfc.section.2.p.1">The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL"
540            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>.
541         </p>
542         <p id="rfc.section.2.p.2">This specification uses the augmented BNF notation defined in <a href="https://tools.ietf.org/html/rfc2616#section-2.1">Section 2.1</a> of <a href="#RFC2616" id="rfc.xref.RFC2616.3"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>, including its rules for linear whitespace (LWS).
543         </p>
544      </div>
545      <div id="header.field.definition">
546         <div id="rfc.iref.h.1"></div>
547         <div id="rfc.iref.c.1"></div>
548         <h1 id="rfc.section.3"><a href="#rfc.section.3">3.</a>&nbsp;<a href="#header.field.definition">Header Field Definition</a></h1>
549         <p id="rfc.section.3.p.1">The Content-Disposition response header field is used to convey additional information about how to process the response payload,
550            and also can be used to attach additional metadata, such as the filename.
551         </p>
552         <div>
553            <h2 id="rfc.section.3.1"><a href="#rfc.section.3.1">3.1</a>&nbsp;Grammar
554            </h2>
555            <div id="rfc.figure.u.1"></div><pre class="inline">  content-disposition = "Content-Disposition" ":"
556                         disposition-type *( ";" disposition-parm )
557
558  disposition-type    = "inline" | "attachment" | disp-ext-type
559                      ; case-insensitive
560  disp-ext-type       = token
561
562  disposition-parm    = filename-parm | disp-ext-parm
563
564  filename-parm       = "filename" "=" value
565                      | "filename*" "=" ext-value
566 
567  disp-ext-parm       = token "=" value
568                      | ext-token "=" ext-value
569  ext-token           = &lt;the characters in token, followed by "*"&gt;
570</pre><div id="rfc.figure.u.2"></div>
571            <p>Defined in <a href="#RFC2616" id="rfc.xref.RFC2616.4"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>:
572            </p><pre class="inline">  token       = &lt;token, defined in <a href="#RFC2616" id="rfc.xref.RFC2616.5"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>, <a href="https://tools.ietf.org/html/rfc2616#section-2.2">Section 2.2</a>&gt;
573  value       = &lt;value, defined in <a href="#RFC2616" id="rfc.xref.RFC2616.6"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>, <a href="https://tools.ietf.org/html/rfc2616#section-3.6">Section 3.6</a>&gt;
574</pre><div id="rfc.figure.u.3"></div>
575            <p>Defined in <a href="#RFC5987" id="rfc.xref.RFC5987.1"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a>:
576            </p><pre class="inline">  ext-value   = &lt;ext-value, defined in <a href="#RFC5987" id="rfc.xref.RFC5987.2"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a>, <a href="https://tools.ietf.org/html/rfc5987#section-3.2">Section 3.2</a>&gt;
577</pre></div>
578         <div id="disposition.type">
579            <h2 id="rfc.section.3.2"><a href="#rfc.section.3.2">3.2</a>&nbsp;<a href="#disposition.type">Disposition Type</a></h2>
580            <p id="rfc.section.3.2.p.1">If the disposition type matches "attachment" (case-insensitively), this indicates that the user agent should not display the
581               response, but directly enter a "save as..." dialog.
582            </p>
583            <p id="rfc.section.3.2.p.2">On the other hand, if it matches "inline" (case-insensitively), this implies default processing.</p>
584            <p id="rfc.section.3.2.p.3">Other disposition types <em class="bcp14">SHOULD</em> be handled the same way as "attachment" (see also <a href="#RFC2183" id="rfc.xref.RFC2183.2"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a>, <a href="https://tools.ietf.org/html/rfc2183#section-2.8">Section 2.8</a>).
585            </p>
586         </div>
587         <div id="disposition.parameter.filename">
588            <h2 id="rfc.section.3.3"><a href="#rfc.section.3.3">3.3</a>&nbsp;<a href="#disposition.parameter.filename">Disposition Parameter: 'Filename'</a></h2>
589            <p id="rfc.section.3.3.p.1">The parameters "filename" and "filename*", to be matched case-insensitively, provide information on how to construct a filename
590               for storing the message payload.
591            </p>
592            <p id="rfc.section.3.3.p.2">Depending on the disposition type, this information might be used right away (in the "save as..." interaction caused for the
593               "attachment" disposition type), or later on (for instance, when the user decides to save the contents of the current page
594               being displayed).
595            </p>
596            <p id="rfc.section.3.3.p.3">"filename" and "filename*" behave the same, except that "filename*" uses the encoding defined in <a href="#RFC5987" id="rfc.xref.RFC5987.3"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a>, allowing the use of characters not present in the ISO-8859-1 character set (<a href="#ISO-8859-1" id="rfc.xref.ISO-8859-1.1"><cite title="Information technology -- 8-bit single-byte coded graphic character sets -- Part 1: Latin alphabet No. 1">[ISO-8859-1]</cite></a>). When both "filename" and "filename*" are present, a recipient <em class="bcp14">SHOULD</em> pick "filename*" and ignore "filename" - this will make it possible to send the same header value to clients that do not support
597               "filename*".
598            </p>
599            <p id="rfc.section.3.3.p.4">It is essential that user agents treat the specified filename as advisory only, thus be very careful in extracting the desired
600               information. In particular:
601            </p>
602            <ul>
603               <li>
604                  <p>When the value contains path separator characters, all but the last segment <em class="bcp14">SHOULD</em> be ignored. This prevents unintentional overwriting of well-known file system location (such as "/etc/passwd").
605                  </p>
606               </li>
607               <li>
608                  <p>Many platforms do not use 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>) to hold type information in the file system, but rely on filename extensions instead. Trusting the server-provided file
609                     extension could introduce a privilege escalation when later on the file is opened locally (consider ".exe"). Thus, recipients
610                     need to ensure that a file extension is used that is safe, optimally matching the media type of the received payload.
611                  </p>
612               </li>
613               <li>
614                  <p>Other aspects recipients need to be aware of are names that have a special meaning in the filesystem or in shell commands,
615                     such as "." and "..", "~", "|", and also device names.
616                  </p>
617               </li>
618            </ul>
619         </div>
620         <div id="disposition.parameter.extensionsS">
621            <h2 id="rfc.section.3.4"><a href="#rfc.section.3.4">3.4</a>&nbsp;<a href="#disposition.parameter.extensionsS">Disposition Parameter: Extensions</a></h2>
622            <p id="rfc.section.3.4.p.1">To enable future extensions, unknown parameters <em class="bcp14">SHOULD</em> be ignored (see also <a href="#RFC2183" id="rfc.xref.RFC2183.3"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a>, <a href="https://tools.ietf.org/html/rfc2183#section-2.8">Section 2.8</a>).
623            </p>
624         </div>
625         <div id="extensibility">
626            <h2 id="rfc.section.3.5"><a href="#rfc.section.3.5">3.5</a>&nbsp;<a href="#extensibility">Extensibility</a></h2>
627            <p id="rfc.section.3.5.p.1">Note that <a href="https://tools.ietf.org/html/rfc2183#section-9">Section 9</a> of <a href="#RFC2183" id="rfc.xref.RFC2183.4"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a> defines IANA registries both for disposition types and disposition parameters. This registry is shared by different protocols
628               using Content-Disposition, such as MIME and HTTP. Therefore, not all registered values may make sense in the context of HTTP.
629            </p>
630         </div>
631      </div>
632      <div>
633         <h1 id="rfc.section.4"><a href="#rfc.section.4">4.</a>&nbsp;Examples
634         </h1>
635         <div id="rfc.figure.u.4"></div>
636         <p>Direct UA to show "save as" dialog, with a filename of "foo.html":</p><pre class="text">Content-Disposition: Attachment; filename=foo.html
637</pre><div id="rfc.figure.u.5"></div>
638         <p>Direct UA to behave as if the Content-Disposition header field wasn't present, but to remember the filename "foo.html" for
639            a subsequent save operation:
640         </p><pre class="text">Content-Disposition: INLINE; FILENAME= "foo.html"
641</pre><div id="rfc.figure.u.6"></div>
642         <p>Direct UA to show "save as" dialog, with a filename of "an example":</p><pre class="text">Content-Disposition: Attachment; Filename*=UTF-8'<b>en</b>'an<b>%20</b>example
643</pre><p>Note that this example uses the extended encoding defined in <a href="#RFC5987" id="rfc.xref.RFC5987.4"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a> to specify that the natural language of the filename is English, and also to encode the space character which is not allowed
644            in the token production.
645         </p>
646         <div id="rfc.figure.u.7"></div>
647         <p>Direct UA to show "save as" dialog, with a filename containing the Unicode character U+20AC (EURO SIGN):</p><pre class="text">Content-Disposition: attachment; filename*= UTF-8''<b>%e2%82%ac</b>%20rates
648</pre><p>Here, the encoding defined in <a href="#RFC5987" id="rfc.xref.RFC5987.5"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a> is also used to encode the non-ISO-8859-1 character.
649         </p>
650         <div id="rfc.figure.u.8"></div>
651         <p>Same as above, but adding the "filename" parameter for compatibility with user agents not implementing RFC 5987:</p><pre class="text">Content-Disposition: attachment; filename="EURO rates";
652                                 filename*=utf-8''<b>%e2%82%ac</b>%20rates
653</pre><p>Note: as of August 2010, many user agents unfortunately did not properly handle unexpected parameters, and some that implement
654            RFC 5987 did not pick the extended parameter when both were present.
655         </p>
656      </div>
657      <div id="i18n">
658         <h1 id="rfc.section.5"><a href="#rfc.section.5">5.</a>&nbsp;<a href="#i18n">Internationalization Considerations</a></h1>
659         <p id="rfc.section.5.p.1">The "filename*" parameter (<a href="#disposition.parameter.filename" title="Disposition Parameter: 'Filename'">Section&nbsp;3.3</a>), using the encoding defined in <a href="#RFC5987" id="rfc.xref.RFC5987.6"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a>, allows the server to transmit characters outside the ISO-8859-1 character set, and also to optionally specify the language
660            in use.
661         </p>
662         <p id="rfc.section.5.p.2">Future parameters might also require internationalization, in which case the same encoding can be used.</p>
663      </div>
664      <div id="security.considerations">
665         <h1 id="rfc.section.6"><a href="#rfc.section.6">6.</a>&nbsp;<a href="#security.considerations">Security Considerations</a></h1>
666         <p id="rfc.section.6.p.1">Using server-supplied information for constructing local filenames introduces many risks. These are summarized in <a href="#disposition.parameter.filename" title="Disposition Parameter: 'Filename'">Section&nbsp;3.3</a>.
667         </p>
668         <p id="rfc.section.6.p.2">Furthermore, implementers also ought to be aware of the Security Considerations applying to HTTP (see <a href="https://tools.ietf.org/html/rfc2616#section-15">Section 15</a> of <a href="#RFC2616" id="rfc.xref.RFC2616.7"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>), and also the parameter encoding defined in <a href="#RFC5987" id="rfc.xref.RFC5987.7"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a> (see <a href="https://tools.ietf.org/html/rfc5987" id="rfc.xref.RFC5987.8">Appendix ERROR: Anchor 'security.considerations' in RFC5987 not found in source file ''.</a>).
669         </p>
670      </div>
671      <div id="iana.considerations">
672         <h1 id="rfc.section.7"><a href="#rfc.section.7">7.</a>&nbsp;<a href="#iana.considerations">IANA Considerations</a></h1>
673         <div id="registry">
674            <h2 id="rfc.section.7.1"><a href="#rfc.section.7.1">7.1</a>&nbsp;<a href="#registry">Registry for Disposition Values and Parameter</a></h2>
675            <p id="rfc.section.7.1.p.1">This specification does not introduce any changes to the registration procedures for disposition values and parameters that
676               are defined in <a href="https://tools.ietf.org/html/rfc2183#section-9">Section 9</a> of <a href="#RFC2183" id="rfc.xref.RFC2183.5"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a>.
677            </p>
678         </div>
679         <div id="header.field.registration">
680            <h2 id="rfc.section.7.2"><a href="#rfc.section.7.2">7.2</a>&nbsp;<a href="#header.field.registration">Header Field Registration</a></h2>
681            <p id="rfc.section.7.2.p.1">This document updates the definition of the Content-Disposition HTTP header field in the permanent HTTP header field registry
682               (see <a href="#RFC3864" id="rfc.xref.RFC3864.1"><cite title="Registration Procedures for Message Header Fields">[RFC3864]</cite></a>).
683            </p>
684            <p id="rfc.section.7.2.p.2"></p>
685            <dl>
686               <dt>Header field name:</dt>
687               <dd>Content-Disposition</dd>
688               <dt>Applicable protocol:</dt>
689               <dd>http</dd>
690               <dt>Status:</dt>
691               <dd>standard</dd>
692               <dt>Author/Change controller:</dt>
693               <dd>IETF</dd>
694               <dt>Specification document:</dt>
695               <dd>this specification (<a href="#header.field.definition" id="rfc.xref.header.field.definition.1" title="Header Field Definition">Section&nbsp;3</a>)
696               </dd>
697            </dl>
698         </div>
699      </div>
700      <div>
701         <h1 id="rfc.section.8"><a href="#rfc.section.8">8.</a>&nbsp;Acknowledgements
702         </h1>
703         <p id="rfc.section.8.p.1">Thanks to Rolf Eike Beer, Alfred Hoenes, and Roar Lauritzsen for their valuable feedback.</p>
704      </div>
705      <h1 id="rfc.references"><a id="rfc.section.9" href="#rfc.section.9">9.</a> References
706      </h1>
707      <h2 id="rfc.references.1"><a href="#rfc.section.9.1" id="rfc.section.9.1">9.1</a> Normative References
708      </h2>
709      <table>
710         <tr>
711            <td class="reference"><b id="ISO-8859-1">[ISO-8859-1]</b></td>
712            <td class="top">International Organization for Standardization, “Information technology -- 8-bit single-byte coded graphic character sets -- Part 1: Latin alphabet No. 1”, ISO/IEC&nbsp;8859-1:1998, 1998.</td>
713         </tr>
714         <tr>
715            <td class="reference"><b id="RFC2119">[RFC2119]</b></td>
716            <td class="top"><a href="mailto:sob@harvard.edu" title="Harvard University">Bradner, S.</a>, “<a href="https://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.
717            </td>
718         </tr>
719         <tr>
720            <td class="reference"><b id="RFC2616">[RFC2616]</b></td>
721            <td class="top"><a href="mailto:fielding@ics.uci.edu" title="University of California, Irvine">Fielding, R.</a>, <a href="mailto:jg@w3.org" title="W3C">Gettys, J.</a>, <a href="mailto:mogul@wrl.dec.com" title="Compaq Computer Corporation">Mogul, J.</a>, <a href="mailto:frystyk@w3.org" title="MIT Laboratory for Computer Science">Frystyk, H.</a>, <a href="mailto:masinter@parc.xerox.com" title="Xerox Corporation">Masinter, L.</a>, <a href="mailto:paulle@microsoft.com" title="Microsoft Corporation">Leach, P.</a>, and <a href="mailto:timbl@w3.org" title="W3C">T. Berners-Lee</a>, “<a href="https://tools.ietf.org/html/rfc2616">Hypertext Transfer Protocol -- HTTP/1.1</a>”, RFC&nbsp;2616, June&nbsp;1999.
722            </td>
723         </tr>
724         <tr>
725            <td class="reference"><b id="RFC5987">[RFC5987]</b></td>
726            <td class="top"><a href="mailto:julian.reschke@greenbytes.de" title="greenbytes GmbH">Reschke, J.</a>, “<a href="https://tools.ietf.org/html/rfc5987">Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers</a>”, RFC&nbsp;5987, August&nbsp;2010.
727            </td>
728         </tr>
729      </table>
730      <h2 id="rfc.references.2"><a href="#rfc.section.9.2" id="rfc.section.9.2">9.2</a> Informative References
731      </h2>
732      <table>
733         <tr>
734            <td class="reference"><b id="RFC2046">[RFC2046]</b></td>
735            <td class="top"><a href="mailto:ned@innosoft.com" title="Innosoft International, Inc.">Freed, N.</a> and <a href="mailto:nsb@nsb.fv.com" title="First Virtual Holdings">N. Borenstein</a>, “<a href="https://tools.ietf.org/html/rfc2046">Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types</a>”, RFC&nbsp;2046, November&nbsp;1996.
736            </td>
737         </tr>
738         <tr>
739            <td class="reference"><b id="RFC2047">[RFC2047]</b></td>
740            <td class="top"><a href="mailto:moore@cs.utk.edu" title="University of Tennessee">Moore, K.</a>, “<a href="https://tools.ietf.org/html/rfc2047">MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text</a>”, RFC&nbsp;2047, November&nbsp;1996.
741            </td>
742         </tr>
743         <tr>
744            <td class="reference"><b id="RFC2183">[RFC2183]</b></td>
745            <td class="top"><a href="mailto:rens@century.com" title="New Century Systems">Troost, R.</a>, <a href="mailto:sdorner@qualcomm.com" title="QUALCOMM Incorporated">Dorner, S.</a>, and <a href="mailto:moore@cs.utk.edu" title="Department of Computer Science">K. Moore</a>, “<a href="https://tools.ietf.org/html/rfc2183">Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field</a>”, RFC&nbsp;2183, August&nbsp;1997.
746            </td>
747         </tr>
748         <tr>
749            <td class="reference"><b id="RFC2231">[RFC2231]</b></td>
750            <td class="top"><a href="mailto:ned.freed@innosoft.com" title="Innosoft International, Inc.">Freed, N.</a> and <a href="mailto:moore@cs.utk.edu" title="University of Tennessee">K. Moore</a>, “<a href="https://tools.ietf.org/html/rfc2231">MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations</a>”, RFC&nbsp;2231, November&nbsp;1997.
751            </td>
752         </tr>
753         <tr>
754            <td class="reference"><b id="RFC3629">[RFC3629]</b></td>
755            <td class="top"><a href="mailto:fyergeau@alis.com" title="Alis Technologies">Yergeau, F.</a>, “<a href="https://tools.ietf.org/html/rfc3629">UTF-8, a transformation format of ISO 10646</a>”, RFC&nbsp;3629, STD&nbsp;63, November&nbsp;2003.
756            </td>
757         </tr>
758         <tr>
759            <td class="reference"><b id="RFC3864">[RFC3864]</b></td>
760            <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="https://tools.ietf.org/html/rfc3864">Registration Procedures for Message Header Fields</a>”, BCP&nbsp;90, RFC&nbsp;3864, September&nbsp;2004.
761            </td>
762         </tr>
763         <tr>
764            <td class="reference"><b id="RFC3986">[RFC3986]</b></td>
765            <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="https://tools.ietf.org/html/rfc3986">Uniform Resource Identifier (URI): Generic Syntax</a>”, RFC&nbsp;3986, STD&nbsp;66, January&nbsp;2005.
766            </td>
767         </tr>
768      </table>
769      <div id="changes.from.rfc2616">
770         <h1 id="rfc.section.A" class="np"><a href="#rfc.section.A">A.</a>&nbsp;<a href="#changes.from.rfc2616">Changes from the RFC 2616 Definition</a></h1>
771         <p id="rfc.section.A.p.1">Compared to <a href="https://tools.ietf.org/html/rfc2616#section-19.5.1">Section 19.5.1</a> of <a href="#RFC2616" id="rfc.xref.RFC2616.8"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>, the following normative changes reflecting actual implementations have been made:
772         </p>
773         <ul>
774            <li>According to RFC 2616, the disposition type "attachment" only applies to content of type "application/octet-stream". This
775               restriction has been removed, because user agents in practice do not check the content type, and it also discourages properly
776               declaring the media type.
777            </li>
778            <li>RFC 2616 only allows "quoted-string" for the filename parameter. This would be an exceptional parameter syntax, and also doesn't
779               reflect actual use.
780            </li>
781            <li>The definition for the disposition type "inline" (<a href="#RFC2183" id="rfc.xref.RFC2183.6"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a>, <a href="https://tools.ietf.org/html/rfc2183#section-2.1">Section 2.1</a>) has been re-added with a suggestion for its processing.
782            </li>
783            <li>This specification requires support for the extended parameter encoding defined in <a href="#RFC5987" id="rfc.xref.RFC5987.9"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a>.
784            </li>
785         </ul>
786      </div>
787      <div id="diffs.compared.to.rfc2183">
788         <h1 id="rfc.section.B"><a href="#rfc.section.B">B.</a>&nbsp;<a href="#diffs.compared.to.rfc2183">Differences compared to RFC 2183</a></h1>
789         <p id="rfc.section.B.p.1"><a href="https://tools.ietf.org/html/rfc2183#section-2">Section 2</a> of <a href="#RFC2183" id="rfc.xref.RFC2183.7"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a> defines several additional disposition parameters: "creation-date", "modification-date", "quoted-date-time", and "size". These
790            do not appear to be implemented by any user agent, thus have been omitted from this specification.
791         </p>
792      </div>
793      <div id="alternatives">
794         <h1 id="rfc.section.C"><a href="#rfc.section.C">C.</a>&nbsp;<a href="#alternatives">Alternative Approaches to Internationalization</a></h1>
795         <p id="rfc.section.C.p.1">By default, HTTP header field parameters cannot carry characters outside the ISO-8859-1 (<a href="#ISO-8859-1" id="rfc.xref.ISO-8859-1.2"><cite title="Information technology -- 8-bit single-byte coded graphic character sets -- Part 1: Latin alphabet No. 1">[ISO-8859-1]</cite></a>) character encoding (see <a href="#RFC2616" id="rfc.xref.RFC2616.9"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>, <a href="https://tools.ietf.org/html/rfc2616#section-2.2">Section 2.2</a>). For the "filename" parameter, this of course is an unacceptable restriction.
796         </p>
797         <p id="rfc.section.C.p.2">Unfortunately, user agent implementers have not managed to come up with an interoperable approach, although the IETF Standards
798            Track specifies exactly one solution (<a href="#RFC2231" id="rfc.xref.RFC2231.1"><cite title="MIME Parameter Value and Encoded Word Extensions: Character Sets, Languages, and Continuations">[RFC2231]</cite></a>, clarified and profiled for HTTP in <a href="#RFC5987" id="rfc.xref.RFC5987.10"><cite title="Applicability of RFC 2231 Encoding to Hypertext Transfer Protocol (HTTP) Headers">[RFC5987]</cite></a>).
799         </p>
800         <p id="rfc.section.C.p.3">For completeness, the sections below describe the various approaches that have been tried, and explains how they are inferior
801            to the RFC 5987 encoding used in this specification.
802         </p>
803         <div id="alternatives.rfc2047">
804            <h2 id="rfc.section.C.1"><a href="#rfc.section.C.1">C.1</a>&nbsp;<a href="#alternatives.rfc2047">RFC 2047 Encoding</a></h2>
805            <p id="rfc.section.C.1.p.1">RFC 2047 defines an encoding mechanism for header fields, but this encoding is not supposed to be used for header field parameters
806               - see <a href="https://tools.ietf.org/html/rfc2047#section-5">Section 5</a> of <a href="#RFC2047" id="rfc.xref.RFC2047.1"><cite title="MIME (Multipurpose Internet Mail Extensions) Part Three: Message Header Extensions for Non-ASCII Text">[RFC2047]</cite></a>:
807            </p>
808            <blockquote id="rfc.section.C.1.p.2" cite="http://tools.ietf.org/html/rfc2047#section-5">
809               <p>An 'encoded-word' MUST NOT appear within a 'quoted-string'.</p>
810               <p>...</p>
811               <p>An 'encoded-word' MUST NOT be used in parameter of a MIME Content-Type or Content-Disposition field, or in any structured
812                  field body except within a 'comment' or 'phrase'.
813               </p>
814            </blockquote>
815            <p id="rfc.section.C.1.p.3">In practice, some user agents implement the encoding, some do not (exposing the encoded string to the user), and some get
816               confused by it.
817            </p>
818         </div>
819         <div id="alternatives.percent">
820            <h2 id="rfc.section.C.2"><a href="#rfc.section.C.2">C.2</a>&nbsp;<a href="#alternatives.percent">Percent Encoding</a></h2>
821            <p id="rfc.section.C.2.p.1">Some user agents accept percent encoded (<a href="#RFC3986" id="rfc.xref.RFC3986.1"><cite title="Uniform Resource Identifier (URI): Generic Syntax">[RFC3986]</cite></a>, <a href="https://tools.ietf.org/html/rfc3986#section-2.1">Section 2.1</a>) sequences of characters encoded using the UTF-8 (<a href="#RFC3629" id="rfc.xref.RFC3629.1"><cite title="UTF-8, a transformation format of ISO 10646">[RFC3629]</cite></a>) character encoding.
822            </p>
823            <p id="rfc.section.C.2.p.2">In practice, this is hard to use because those user agents that do not support it will display the escaped character sequence
824               to the user.
825            </p>
826            <p id="rfc.section.C.2.p.3">Furthermore, the first user agent to implement this did choose the encoding based on local settings; thus making it very hard
827               to use in multi-lingual environments.
828            </p>
829         </div>
830         <div id="alternatives.sniff">
831            <h2 id="rfc.section.C.3"><a href="#rfc.section.C.3">C.3</a>&nbsp;<a href="#alternatives.sniff">Encoding Sniffing</a></h2>
832            <p id="rfc.section.C.3.p.1">Some user agents inspect the value (which defaults to ISO-8859-1) and switch to UTF-8 when it seems to be more likely to be
833               the correct interpretation.
834            </p>
835            <p id="rfc.section.C.3.p.2">As with the approaches above, this is not interoperable and furthermore risks misinterpreting the actual value.</p>
836         </div>
837         <div id="alternatives.implementations">
838            <h2 id="rfc.section.C.4"><a href="#rfc.section.C.4">C.4</a>&nbsp;<a href="#alternatives.implementations">Implementations</a></h2>
839            <p id="rfc.section.C.4.p.1">Unfortunately, as of August 2010, neither the encoding defined in RFCs 2231 and 5789, nor any of the alternate approaches
840               discussed above was implemented interoperably. Thus, this specification recommends the approach defined in RFC 5987, which
841               at least has the advantage of actually being specified properly.
842            </p>
843            <p id="rfc.section.C.4.p.2">The table below shows the implementation support for the various approaches: <span class="comment" id="impls">[<a href="#impls" class="smpl">impls</a>: Discuss: should we mention the implementation status of actual UAs in a RFC? Up to the IESG to decide...]</span>
844            </p>
845            <div id="rfc.table.u.1">
846               <table class="tt full left" cellpadding="3" cellspacing="0">
847                  <thead>
848                     <tr>
849                        <th>User Agent</th>
850                        <th>RFC 2231/5987</th>
851                        <th>RFC 2047</th>
852                        <th>Percent Encoding</th>
853                        <th>Encoding Sniffing</th>
854                     </tr>
855                  </thead>
856                  <tbody>
857                     <tr>
858                        <td class="left">Chrome</td>
859                        <td class="left">no</td>
860                        <td class="left">yes</td>
861                        <td class="left">yes</td>
862                        <td class="left">yes</td>
863                     </tr>
864                     <tr>
865                        <td class="left">Firefox</td>
866                        <td class="left">yes (*)</td>
867                        <td class="left">yes</td>
868                        <td class="left">no</td>
869                        <td class="left">yes</td>
870                     </tr>
871                     <tr>
872                        <td class="left">Internet Explorer</td>
873                        <td class="left">no</td>
874                        <td class="left">no</td>
875                        <td class="left">yes</td>
876                        <td class="left">no</td>
877                     </tr>
878                     <tr>
879                        <td class="left">Konqueror</td>
880                        <td class="left">yes</td>
881                        <td class="left">no</td>
882                        <td class="left">no</td>
883                        <td class="left">no</td>
884                     </tr>
885                     <tr>
886                        <td class="left">Opera</td>
887                        <td class="left">yes (*)</td>
888                        <td class="left">no</td>
889                        <td class="left">no</td>
890                        <td class="left">no</td>
891                     </tr>
892                     <tr>
893                        <td class="left">Safari</td>
894                        <td class="left">no</td>
895                        <td class="left">no</td>
896                        <td class="left">no</td>
897                        <td class="left">yes</td>
898                     </tr>
899                  </tbody>
900               </table>
901               <p>(*) Does not implement the fallback behavior to "filename" described in <a href="#disposition.parameter.filename" title="Disposition Parameter: 'Filename'">Section&nbsp;3.3</a>.
902               </p>
903            </div>
904         </div>
905      </div>
906      <div id="change.log">
907         <h1 id="rfc.section.D"><a href="#rfc.section.D">D.</a>&nbsp;<a href="#change.log">Change Log (to be removed by RFC Editor before publication)</a></h1>
908         <div>
909            <h2 id="rfc.section.D.1"><a href="#rfc.section.D.1">D.1</a>&nbsp;Since draft-reschke-rfc2183-in-http-00
910            </h2>
911            <p id="rfc.section.D.1.p.1">Adjust terminology ("header" -&gt; "header field"). Update rfc2231-in-http reference.</p>
912         </div>
913         <div>
914            <h2 id="rfc.section.D.2"><a href="#rfc.section.D.2">D.2</a>&nbsp;Since draft-reschke-rfc2183-in-http-01
915            </h2>
916            <p id="rfc.section.D.2.p.1">Update rfc2231-in-http reference. Actually define the "filename" parameter. Add internationalization considerations. Add examples
917               using the RFC 5987 encoding. Add overview over other approaches, plus a table reporting implementation status. Add and resolve
918               issue "nodep2183". Add issues "asciivsiso", "deplboth", "quoted", and "registry".
919            </p>
920         </div>
921         <div>
922            <h2 id="rfc.section.D.3"><a href="#rfc.section.D.3">D.3</a>&nbsp;Since draft-reschke-rfc2183-in-http-02
923            </h2>
924            <p id="rfc.section.D.3.p.1">Add and close issue "docfallback". Close issues "asciivsiso", "deplboth", "quoted", and "registry".</p>
925         </div>
926         <div>
927            <h2 id="rfc.section.D.4"><a href="#rfc.section.D.4">D.4</a>&nbsp;Since draft-reschke-rfc2183-in-http-03
928            </h2>
929            <p id="rfc.section.D.4.p.1">Updated to be a Working Draft of the IETF HTTPbis Working Group.</p>
930         </div>
931      </div>
932      <h1 id="rfc.index"><a href="#rfc.index">Index</a></h1>
933      <p class="noprint"><a href="#rfc.index.C">C</a> <a href="#rfc.index.H">H</a> <a href="#rfc.index.I">I</a> <a href="#rfc.index.R">R</a>
934      </p>
935      <div class="print2col">
936         <ul class="ind">
937            <li><a id="rfc.index.C" href="#rfc.index.C"><b>C</b></a><ul>
938                  <li>Content-Disposition header&nbsp;&nbsp;<a href="#rfc.iref.c.1"><b>3</b></a>, <a href="#rfc.xref.header.field.definition.1">7.2</a></li>
939               </ul>
940            </li>
941            <li><a id="rfc.index.H" href="#rfc.index.H"><b>H</b></a><ul>
942                  <li>Headers&nbsp;&nbsp;
943                     <ul>
944                        <li>Content-Disposition&nbsp;&nbsp;<a href="#rfc.iref.h.1"><b>3</b></a>, <a href="#rfc.xref.header.field.definition.1">7.2</a></li>
945                     </ul>
946                  </li>
947               </ul>
948            </li>
949            <li><a id="rfc.index.I" href="#rfc.index.I"><b>I</b></a><ul>
950                  <li><em>ISO-8859-1</em>&nbsp;&nbsp;<a href="#rfc.xref.ISO-8859-1.1">3.3</a>, <a href="#ISO-8859-1"><b>9.1</b></a>, <a href="#rfc.xref.ISO-8859-1.2">C</a></li>
951               </ul>
952            </li>
953            <li><a id="rfc.index.R" href="#rfc.index.R"><b>R</b></a><ul>
954                  <li><em>RFC2046</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2046.1">3.3</a>, <a href="#RFC2046"><b>9.2</b></a></li>
955                  <li><em>RFC2047</em>&nbsp;&nbsp;<a href="#RFC2047"><b>9.2</b></a>, <a href="#rfc.xref.RFC2047.1">C.1</a><ul>
956                        <li><em>Section 5</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2047.1">C.1</a></li>
957                     </ul>
958                  </li>
959                  <li><em>RFC2119</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2119.1">2</a>, <a href="#RFC2119"><b>9.1</b></a></li>
960                  <li><em>RFC2183</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2183.1">1</a>, <a href="#rfc.xref.RFC2183.2">3.2</a>, <a href="#rfc.xref.RFC2183.3">3.4</a>, <a href="#rfc.xref.RFC2183.4">3.5</a>, <a href="#rfc.xref.RFC2183.5">7.1</a>, <a href="#RFC2183"><b>9.2</b></a>, <a href="#rfc.xref.RFC2183.6">A</a>, <a href="#rfc.xref.RFC2183.7">B</a><ul>
961                        <li><em>Section 2</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2183.7">B</a></li>
962                        <li><em>Section 2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2183.6">A</a></li>
963                        <li><em>Section 2.8</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2183.2">3.2</a>, <a href="#rfc.xref.RFC2183.3">3.4</a></li>
964                        <li><em>Section 9</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2183.4">3.5</a>, <a href="#rfc.xref.RFC2183.5">7.1</a></li>
965                     </ul>
966                  </li>
967                  <li><em>RFC2231</em>&nbsp;&nbsp;<a href="#RFC2231"><b>9.2</b></a>, <a href="#rfc.xref.RFC2231.1">C</a></li>
968                  <li><em>RFC2616</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.1">1</a>, <a href="#rfc.xref.RFC2616.2">1</a>, <a href="#rfc.xref.RFC2616.3">2</a>, <a href="#rfc.xref.RFC2616.4">3.1</a>, <a href="#rfc.xref.RFC2616.5">3.1</a>, <a href="#rfc.xref.RFC2616.6">3.1</a>, <a href="#rfc.xref.RFC2616.7">6</a>, <a href="#RFC2616"><b>9.1</b></a>, <a href="#rfc.xref.RFC2616.8">A</a>, <a href="#rfc.xref.RFC2616.9">C</a><ul>
969                        <li><em>Section 2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.3">2</a></li>
970                        <li><em>Section 2.2</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.5">3.1</a>, <a href="#rfc.xref.RFC2616.9">C</a></li>
971                        <li><em>Section 3.6</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.6">3.1</a></li>
972                        <li><em>Section 15.5</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.2">1</a></li>
973                        <li><em>Section 15</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.7">6</a></li>
974                        <li><em>Section 19.5.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.1">1</a>, <a href="#rfc.xref.RFC2616.8">A</a></li>
975                     </ul>
976                  </li>
977                  <li><em>RFC3629</em>&nbsp;&nbsp;<a href="#RFC3629"><b>9.2</b></a>, <a href="#rfc.xref.RFC3629.1">C.2</a></li>
978                  <li><em>RFC3864</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3864.1">7.2</a>, <a href="#RFC3864"><b>9.2</b></a></li>
979                  <li><em>RFC3986</em>&nbsp;&nbsp;<a href="#RFC3986"><b>9.2</b></a>, <a href="#rfc.xref.RFC3986.1">C.2</a><ul>
980                        <li><em>Section 2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.1">C.2</a></li>
981                     </ul>
982                  </li>
983                  <li><em>RFC5987</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5987.1">3.1</a>, <a href="#rfc.xref.RFC5987.2">3.1</a>, <a href="#rfc.xref.RFC5987.3">3.3</a>, <a href="#rfc.xref.RFC5987.4">4</a>, <a href="#rfc.xref.RFC5987.5">4</a>, <a href="#rfc.xref.RFC5987.6">5</a>, <a href="#rfc.xref.RFC5987.7">6</a>, <a href="#rfc.xref.RFC5987.8">6</a>, <a href="#RFC5987"><b>9.1</b></a>, <a href="#rfc.xref.RFC5987.9">A</a>, <a href="#rfc.xref.RFC5987.10">C</a><ul>
984                        <li><em>Section 3.2</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5987.2">3.1</a></li>
985                     </ul>
986                  </li>
987               </ul>
988            </li>
989         </ul>
990      </div>
991      <div class="avoidbreak">
992         <h1 id="rfc.authors"><a href="#rfc.authors">Author's Address</a></h1>
993         <p><b>Julian F. Reschke</b><br>greenbytes GmbH<br>Hafenweg 16<br>Muenster, NW&nbsp;48155<br>Germany<br>Email: <a href="mailto:julian.reschke@greenbytes.de">julian.reschke@greenbytes.de</a><br>URI: <a href="http://greenbytes.de/tech/webdav/">http://greenbytes.de/tech/webdav/</a></p>
994      </div>
995   </body>
996</html>
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