Source: https://trac.ietf.org/trac/httpbis/browser/draft-ietf-httpbis/latest/p3-payload.html?rev=560
Timestamp: 2019-09-20 04:07:56
Document Index: 674291192

Matched Legal Cases: ['art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art4', 'art4', 'art 4', 'art4', 'art5', 'art5', 'art 5', 'art5', 'art6', 'art6', 'art 6', 'art6', 'art 1', 'art5', 'art5', 'art 5', 'art5', 'art1', 'art1', 'art 1', 'art1', 'art5', 'art5', 'art 5', 'art5', 'art6', 'art6', 'art 6', 'art6', 'art4', 'art4', 'art 4', 'art4', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art2', 'art2', 'art 2', 'art2', 'art6', 'art6', 'art 6', 'art6', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art6', 'art6', 'art 6', 'art6', 'art 1', 'art 2', 'art 4', 'art 5', 'art 6', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art1', 'art1', 'art 1', 'art1', 'art5', 'art5', 'art 5', 'art5', 'art6', 'art6', 'art 6', 'art6', 'art1', 'art5', 'art6', 'art4', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art1', 'art2', 'art2', 'art2', 'art2', 'art4', 'art4', 'art4', 'art4', 'art4', 'art4', 'art5', 'art5', 'art5', 'art5', 'art5', 'art5', 'art5', 'art5', 'art5', 'art6', 'art6', 'art6', 'art6', 'art6', 'art6', 'art6', 'art6', 'art6', 'art6', 'art6']

source: draft-ietf-httpbis/latest/p3-payload.html @ 560
Last change on this file since 560 was 560, checked in by julian.reschke@…, 11 years ago
content: "March 2009";
<link rel="Appendix" title="C Compatibility with Previous Versions" href="#rfc.section.C">
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<td class="header left">HTTPbis Working Group</td>
<td class="header left">Expires: September 2009</td>
<td class="header right">March 12, 2009</td>
<p>This Internet-Draft is submitted to IETF pursuant to, and in full conformance with, the provisions of BCP 78 and BCP 79. This
document may contain material from IETF Documents or IETF Contributions published or made publicly available before November
<p>This Internet-Draft will expire in September 2009.</p>
<p>This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents in effect on the date
of publication of this document (<a href="http://trustee.ietf.org/license-info">http://trustee.ietf.org/license-info</a>). Please review these documents carefully, as they describe your rights and restrictions with respect to this document.
<p>The changes in this draft are summarized in <a href="#changes.since.06" title="Since draft-ietf-httpbis-p3-payload-06">Appendix&nbsp;E.8</a>.
<li class="tocline1">2.4&nbsp;&nbsp;&nbsp;<a href="#language.tags">Language Tags</a></li>
<li class="tocline1">6.1&nbsp;&nbsp;&nbsp;<a href="#message.header.registration">Message Header Registration</a></li>
<li class="tocline1">A.3&nbsp;&nbsp;&nbsp;<a href="#conversion.of.date.formats">Conversion of Date Formats</a></li>
<li class="tocline1">A.4&nbsp;&nbsp;&nbsp;<a href="#introduction.of.content-encoding">Introduction of Content-Encoding</a></li>
<li class="tocline1">A.5&nbsp;&nbsp;&nbsp;<a href="#no.content-transfer-encoding">No Content-Transfer-Encoding</a></li>
<li class="tocline1">A.6&nbsp;&nbsp;&nbsp;<a href="#introduction.of.transfer-encoding">Introduction of Transfer-Encoding</a></li>
<li class="tocline1">A.7&nbsp;&nbsp;&nbsp;<a href="#mhtml.line.length">MHTML and Line Length Limitations</a></li>
<li class="tocline0">C.&nbsp;&nbsp;&nbsp;<a href="#compatibility">Compatibility with Previous Versions</a><ul class="toc">
<li class="tocline1">C.1&nbsp;&nbsp;&nbsp;<a href="#changes.from.rfc.2068">Changes from RFC 2068</a></li>
<li class="tocline1">C.2&nbsp;&nbsp;&nbsp;<a href="#changes.from.rfc.2616">Changes from RFC 2616</a></li>
<li class="tocline0">D.&nbsp;&nbsp;&nbsp;<a href="#collected.abnf">Collected ABNF</a></li>
<li class="tocline0">E.&nbsp;&nbsp;&nbsp;<a href="#change.log">Change Log (to be removed by RFC Editor before publication)</a><ul class="toc">
<li class="tocline1">E.1&nbsp;&nbsp;&nbsp;<a href="#rfc.section.E.1">Since RFC2616</a></li>
<li class="tocline1">E.2&nbsp;&nbsp;&nbsp;<a href="#rfc.section.E.2">Since draft-ietf-httpbis-p3-payload-00</a></li>
<li class="tocline1">E.3&nbsp;&nbsp;&nbsp;<a href="#rfc.section.E.3">Since draft-ietf-httpbis-p3-payload-01</a></li>
<li class="tocline1">E.4&nbsp;&nbsp;&nbsp;<a href="#changes.since.02">Since draft-ietf-httpbis-p3-payload-02</a></li>
<li class="tocline1">E.5&nbsp;&nbsp;&nbsp;<a href="#changes.since.03">Since draft-ietf-httpbis-p3-payload-03</a></li>
<li class="tocline1">E.6&nbsp;&nbsp;&nbsp;<a href="#changes.since.04">Since draft-ietf-httpbis-p3-payload-04</a></li>
<li class="tocline1">E.7&nbsp;&nbsp;&nbsp;<a href="#changes.since.05">Since draft-ietf-httpbis-p3-payload-05</a></li>
<li class="tocline1">E.8&nbsp;&nbsp;&nbsp;<a href="#changes.since.06">Since draft-ietf-httpbis-p3-payload-06</a></li>
payload is intended to be interpreted by a recipient, the request header fields that may influence content selection, and
<p id="rfc.section.1.2.p.1">This specification uses the ABNF syntax defined in <a href="p1-messaging.html#notation" title="Syntax Notation">Section 1.2</a> of <a href="#Part1" id="rfc.xref.Part1.1"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> (which extends the syntax defined in <a href="#RFC5234" id="rfc.xref.RFC5234.1"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a> with a list rule). <a href="#collected.abnf" title="Collected ABNF">Appendix&nbsp;D</a> shows the collected ABNF, with the list rule expanded.
<div id="rfc.figure.u.1"></div><pre class="inline"> <a href="#core.rules" class="smpl">quoted-string</a> = &lt;quoted-string, defined in <a href="#Part1" id="rfc.xref.Part1.3"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#basic.rules" title="Basic Rules">Section 1.2.2</a>&gt;
<a href="#core.rules" class="smpl">token</a> = &lt;token, defined in <a href="#Part1" id="rfc.xref.Part1.4"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#basic.rules" title="Basic Rules">Section 1.2.2</a>&gt;
<div id="rfc.figure.u.2"></div><pre class="inline"> <a href="#abnf.dependencies" class="smpl">absolute-URI</a> = &lt;absolute-URI, defined in <a href="#Part1" id="rfc.xref.Part1.6"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.1</a>&gt;
<a href="#abnf.dependencies" class="smpl">Content-Length</a> = &lt;Content-Length, defined in <a href="#Part1" id="rfc.xref.Part1.7"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#header.content-length" title="Content-Length">Section 8.2</a>&gt;
<a href="#abnf.dependencies" class="smpl">message-header</a> = &lt;message-header, defined in <a href="#Part1" id="rfc.xref.Part1.8"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#message.headers" title="Message Headers">Section 4.2</a>&gt;
<a href="#abnf.dependencies" class="smpl">partial-URI</a> = &lt;partial-URI, defined in <a href="#Part1" id="rfc.xref.Part1.9"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#uri" title="Uniform Resource Identifiers">Section 2.1</a>&gt;
<a href="#abnf.dependencies" class="smpl">qvalue</a> = &lt;qvalue, defined in <a href="#Part1" id="rfc.xref.Part1.10"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#quality.values" title="Quality Values">Section 3.5</a>&gt;
</pre><div id="rfc.figure.u.3"></div><pre class="inline"> <a href="#abnf.dependencies" class="smpl">Last-Modified</a> = &lt;Last-Modified, defined in <a href="#Part4" id="rfc.xref.Part4.1"><cite title="HTTP/1.1, part 4: Conditional Requests">[Part4]</cite></a>, <a href="p4-conditional.html#header.last-modified" title="Last-Modified">Section 6.6</a>&gt;
</pre><div id="rfc.figure.u.4"></div><pre class="inline"> <a href="#abnf.dependencies" class="smpl">Content-Range</a> = &lt;Content-Range, defined in <a href="#Part5" id="rfc.xref.Part5.1"><cite title="HTTP/1.1, part 5: Range Requests and Partial Responses">[Part5]</cite></a>, <a href="p5-range.html#header.content-range" title="Content-Range">Section 5.2</a>&gt;
</pre><div id="rfc.figure.u.5"></div><pre class="inline"> <a href="#abnf.dependencies" class="smpl">Expires</a> = &lt;Expires, defined in <a href="#Part6" id="rfc.xref.Part6.1"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>, <a href="p6-cache.html#header.expires" title="Expires">Section 3.3</a>&gt;
<p id="rfc.section.2.1.p.4"> HTTP character sets are identified by case-insensitive tokens. The complete set of tokens is defined by the IANA Character
<div id="rfc.figure.u.6"></div><pre class="inline"><span id="rfc.iref.g.1"></span> <a href="#rule.charset" class="smpl">charset</a> = <a href="#core.rules" class="smpl">token</a>
Character Set registry <em class="bcp14">MUST</em> represent the character set defined by that registry. Applications <em class="bcp14">SHOULD</em> limit their use of character sets to those defined by the IANA registry.
<p id="rfc.section.2.1.p.7">HTTP uses charset in two contexts: within an Accept-Charset request header (in which the charset value is an unquoted token)
and as the value of a parameter in a Content-Type header (within a request or response), in which case the parameter value
of the charset parameter may be quoted.
<p id="rfc.section.2.1.p.8">Implementors should be aware of IETF character set requirements <a href="#RFC3629" id="rfc.xref.RFC3629.1"><cite title="UTF-8, a transformation format of ISO 10646">[RFC3629]</cite></a> <a href="#RFC2277" id="rfc.xref.RFC2277.1"><cite title="IETF Policy on Character Sets and Languages">[RFC2277]</cite></a>.
guess." Senders wishing to defeat this behavior <em class="bcp14">MAY</em> include a charset parameter even when the charset is ISO-8859-1 (<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>) and <em class="bcp14">SHOULD</em> do so when it is known that it will not confuse the recipient.
<div id="rfc.figure.u.7"></div><pre class="inline"><span id="rfc.iref.g.2"></span> <a href="#content.codings" class="smpl">content-coding</a> = <a href="#core.rules" class="smpl">token</a>
<dd>An encoding format produced by the file compression program "gzip" (GNU zip) as described in <a href="#RFC1952" id="rfc.xref.RFC1952.1"><cite title="GZIP file format specification version 4.3">[RFC1952]</cite></a>. This format is a Lempel-Ziv coding (LZ77) with a 32 bit CRC.
<dd>The "zlib" format defined in <a href="#RFC1950" id="rfc.xref.RFC1950.1"><cite title="ZLIB Compressed Data Format Specification version 3.3">[RFC1950]</cite></a> in combination with the "deflate" compression mechanism described in <a href="#RFC1951" id="rfc.xref.RFC1951.1"><cite title="DEFLATE Compressed Data Format Specification version 1.3">[RFC1951]</cite></a>.
<p id="rfc.section.2.3.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 Content-Type (<a href="#header.content-type" id="rfc.xref.header.content-type.1" title="Content-Type">Section&nbsp;5.9</a>) and Accept (<a href="#header.accept" id="rfc.xref.header.accept.1" title="Accept">Section&nbsp;5.1</a>) header fields in order to provide open and extensible data typing and type negotiation.
<div id="rfc.figure.u.8"></div><pre class="inline"><span id="rfc.iref.g.4"></span><span id="rfc.iref.g.5"></span><span id="rfc.iref.g.6"></span> <a href="#media.types" class="smpl">media-type</a> = <a href="#media.types" class="smpl">type</a> "/" <a href="#media.types" class="smpl">subtype</a> *( <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> <a href="#rule.parameter" class="smpl">parameter</a> )
<p id="rfc.section.2.3.p.3"> Parameters <em class="bcp14">MAY</em> follow the type/subtype in the form of attribute/value pairs.
<div id="rfc.figure.u.9"></div><pre class="inline"><span id="rfc.iref.g.7"></span><span id="rfc.iref.g.8"></span><span id="rfc.iref.g.9"></span> <a href="#rule.parameter" class="smpl">parameter</a> = <a href="#rule.parameter" class="smpl">attribute</a> "=" <a href="#rule.parameter" class="smpl">value</a>
<a href="#rule.parameter" class="smpl">value</a> = <a href="#core.rules" class="smpl">token</a> / <a href="#core.rules" class="smpl">quoted-string</a>
<p id="rfc.section.2.3.p.6">A parameter value that matches the <a href="#core.rules" class="smpl">token</a> production may be transmitted as either a token or within a quoted-string. The quoted and unquoted values are equivalent.
multipart types share a common syntax, as defined in <a href="http://tools.ietf.org/html/rfc2046#section-5.1.1">Section 5.1.1</a> of <a href="#RFC2046" id="rfc.xref.RFC2046.2"><cite title="Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types">[RFC2046]</cite></a>, and <em class="bcp14">MUST</em> include a boundary parameter as part of the media type value. The message body is itself a protocol element and <em class="bcp14">MUST</em> therefore use only CRLF to represent line breaks between body-parts. Unlike in RFC 2046, the epilogue of any multipart message <em class="bcp14">MUST</em> be empty; HTTP applications <em class="bcp14">MUST NOT</em> transmit the epilogue (even if the original multipart contains an epilogue). These restrictions exist in order to preserve
is the "multipart/byteranges" type (<a href="p5-range.html#internet.media.type.multipart.byteranges" title="Internet Media Type multipart/byteranges">Appendix A</a> of <a href="#Part5" id="rfc.xref.Part5.2"><cite title="HTTP/1.1, part 5: Range Requests and Partial Responses">[Part5]</cite></a>) when it appears in a 206 (Partial Content) response. In all other cases, an HTTP user agent <em class="bcp14">SHOULD</em> follow the same or similar behavior as a MIME user agent would upon receipt of a multipart type. The MIME header fields within
<p id="rfc.section.2.4.p.1">A language tag identifies a natural language spoken, written, or otherwise conveyed by human beings for communication of information
<p id="rfc.section.2.4.p.2">The syntax and registry of HTTP language tags is the same as that defined by <a href="#RFC1766" id="rfc.xref.RFC1766.1"><cite title="Tags for the Identification of Languages">[RFC1766]</cite></a>. In summary, a language tag is composed of 1 or more parts: A primary language tag and a possibly empty series of subtags:
<div id="rfc.figure.u.10"></div><pre class="inline"><span id="rfc.iref.g.10"></span><span id="rfc.iref.g.11"></span><span id="rfc.iref.g.12"></span> <a href="#language.tags" class="smpl">language-tag</a> = <a href="#language.tags" class="smpl">primary-tag</a> *( "-" <a href="#language.tags" class="smpl">subtag</a> )
<a href="#language.tags" class="smpl">primary-tag</a> = 1*8<a href="#notation" class="smpl">ALPHA</a>
<a href="#language.tags" class="smpl">subtag</a> = 1*8<a href="#notation" class="smpl">ALPHA</a>
</pre><p id="rfc.section.2.4.p.4">White space is not allowed within the tag and all tags are case-insensitive. The name space of language tags is administered
<div id="rfc.figure.u.11"></div><pre class="text"> en, en-US, en-cockney, i-cherokee, x-pig-latin
</pre><p id="rfc.section.2.4.p.6">where any two-letter primary-tag is an ISO-639 language abbreviation and any two-letter initial subtag is an ISO-3166 country
by the request.
<div id="rfc.figure.u.12"></div><pre class="inline"><span id="rfc.iref.g.13"></span><span id="rfc.iref.g.14"></span> <a href="#entity.header.fields" class="smpl">entity-header</a> = <a href="#header.content-encoding" class="smpl">Content-Encoding</a> ; <a href="#header.content-encoding" id="rfc.xref.header.content-encoding.2" title="Content-Encoding">Section&nbsp;5.5</a>
/ <a href="#header.content-language" class="smpl">Content-Language</a> ; <a href="#header.content-language" id="rfc.xref.header.content-language.1" title="Content-Language">Section&nbsp;5.6</a>
/ <a href="#abnf.dependencies" class="smpl">Content-Length</a> ; <a href="#Part1" id="rfc.xref.Part1.11"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#header.content-length" title="Content-Length">Section 8.2</a>
/ <a href="#header.content-location" class="smpl">Content-Location</a> ; <a href="#header.content-location" id="rfc.xref.header.content-location.1" title="Content-Location">Section&nbsp;5.7</a>
/ <a href="#header.content-md5" class="smpl">Content-MD5</a> ; <a href="#header.content-md5" id="rfc.xref.header.content-md5.1" title="Content-MD5">Section&nbsp;5.8</a>
/ <a href="#abnf.dependencies" class="smpl">Content-Range</a> ; <a href="#Part5" id="rfc.xref.Part5.3"><cite title="HTTP/1.1, part 5: Range Requests and Partial Responses">[Part5]</cite></a>, <a href="p5-range.html#header.content-range" title="Content-Range">Section 5.2</a>
/ <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;5.9</a>
/ <a href="#abnf.dependencies" class="smpl">Expires</a> ; <a href="#Part6" id="rfc.xref.Part6.2"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>, <a href="p6-cache.html#header.expires" title="Expires">Section 3.3</a>
/ <a href="#abnf.dependencies" class="smpl">Last-Modified</a> ; <a href="#Part4" id="rfc.xref.Part4.2"><cite title="HTTP/1.1, part 4: Conditional Requests">[Part4]</cite></a>, <a href="p4-conditional.html#header.last-modified" title="Last-Modified">Section 6.6</a>
/ <a href="#entity.header.fields" class="smpl">extension-header</a>
<a href="#entity.header.fields" class="smpl">extension-header</a> = <a href="#abnf.dependencies" class="smpl">message-header</a>
<div id="rfc.figure.u.13"></div><pre class="inline"><span id="rfc.iref.g.15"></span> <a href="#entity.body" class="smpl">entity-body</a> = *<a href="#notation" class="smpl">OCTET</a>
</pre><p id="rfc.section.3.2.p.3">An entity-body is only present in a message when a message-body is present, as described in <a href="p1-messaging.html#message.body" title="Message Body">Section 4.3</a> of <a href="#Part1" id="rfc.xref.Part1.12"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. The entity-body is obtained from the message-body by decoding any Transfer-Encoding that might have been applied to ensure
<div id="rfc.figure.u.14"></div><pre class="text"> entity-body := Content-Encoding( Content-Type( data ) )
<p id="rfc.section.3.2.2.p.1">The entity-length of a message is the length of the message-body before any transfer-codings have been applied. <a href="p1-messaging.html#message.length" title="Message Length">Section 4.4</a> of <a href="#Part1" id="rfc.xref.Part1.13"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> defines how the transfer-length of a message-body is determined.
capabilities and user preferences: Accept (<a href="#header.accept" id="rfc.xref.header.accept.2" title="Accept">Section&nbsp;5.1</a>), Accept-Charset (<a href="#header.accept-charset" id="rfc.xref.header.accept-charset.1" title="Accept-Charset">Section&nbsp;5.2</a>), Accept-Encoding (<a href="#header.accept-encoding" id="rfc.xref.header.accept-encoding.2" title="Accept-Encoding">Section&nbsp;5.3</a>), Accept-Language (<a href="#header.accept-language" id="rfc.xref.header.accept-language.1" title="Accept-Language">Section&nbsp;5.4</a>), and User-Agent (<a href="p2-semantics.html#header.user-agent" title="User-Agent">Section 9.9</a> of <a href="#Part2" id="rfc.xref.Part2.1"><cite title="HTTP/1.1, part 2: Message Semantics">[Part2]</cite></a>). However, an origin server is not limited to these dimensions and <em class="bcp14">MAY</em> vary the response based on any aspect of the request, including information outside the request-header fields or within extension
<p id="rfc.section.4.1.p.5">The Vary header field (<a href="p6-cache.html#header.vary" title="Vary">Section 3.5</a> of <a href="#Part6" id="rfc.xref.Part6.3"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) can be used to express the parameters the server uses to select a representation that is subject to server-driven negotiation.
<p id="rfc.section.5.p.1">This section defines the syntax and semantics of HTTP/1.1 header fields related to the payload of messages.</p>
<p id="rfc.section.5.p.2">For entity-header fields, both sender and recipient refer to either the client or the server, depending on who sends and who
<p id="rfc.section.5.1.p.1">The request-header field "Accept" can be used to specify certain media types which are acceptable for the response. Accept
headers can be used to indicate that the request is specifically limited to a small set of desired types, as in the case of
a request for an in-line image.
<div id="rfc.figure.u.15"></div><pre class="inline"><span id="rfc.iref.g.16"></span><span id="rfc.iref.g.17"></span><span id="rfc.iref.g.18"></span><span id="rfc.iref.g.19"></span><span id="rfc.iref.g.20"></span> <a href="#header.accept" class="smpl">Accept</a> = "Accept" ":" <a href="#core.rules" class="smpl">OWS</a> <a href="#header.accept" class="smpl">Accept-v</a>
<a href="#header.accept" class="smpl">Accept-v</a> = #( <a href="#header.accept" class="smpl">media-range</a> [ <a href="#header.accept" class="smpl">accept-params</a> ] )
<a href="#header.accept" class="smpl">accept-ext</a> = <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> <a href="#core.rules" class="smpl">token</a>
[ "=" ( <a href="#core.rules" class="smpl">token</a> / <a href="#core.rules" class="smpl">quoted-string</a> ) ]
agent to indicate the relative degree of preference for that media-range, using the qvalue scale from 0 to 1 (<a href="p1-messaging.html#quality.values" title="Quality Values">Section 3.5</a> of <a href="#Part1" id="rfc.xref.Part1.14"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). The default value is q=1.
<div id="rfc.figure.u.16"></div><pre class="text"> Accept: audio/*; q=0.2, audio/basic
<div id="rfc.figure.u.17"></div><pre class="text"> Accept: text/plain; q=0.5, text/html,
<div id="rfc.figure.u.18"></div><pre class="text"> Accept: text/*, text/html, text/html;level=1, */*
</pre><p id="rfc.section.5.1.p.14">have the following precedence: </p>
<li>text/html;level=1</li>
<li>text/html</li>
<p id="rfc.section.5.1.p.15">The media type quality factor associated with a given type is determined by finding the media range with the highest precedence
<div id="rfc.figure.u.19"></div><pre class="text"> Accept: text/*;q=0.3, text/html;q=0.7, text/html;level=1,
</pre><p id="rfc.section.5.1.p.17">would cause the following values to be associated:</p>
<td>text/html;level=1</td>
<td>text/html</td>
<td>0.7</td>
<td>text/plain</td>
<td>0.3</td>
<td>image/jpeg</td>
<td>0.5</td>
<td>text/html;level=2</td>
<td>0.4</td>
<td>text/html;level=3</td>
<p id="rfc.section.5.1.p.18"> <b>Note:</b> A user agent might be provided with a default set of quality values for certain media ranges. However, unless the user agent
<p id="rfc.section.5.2.p.1">The request-header field "Accept-Charset" can be used to indicate what character sets are acceptable for the response. This
<div id="rfc.figure.u.20"></div><pre class="inline"><span id="rfc.iref.g.21"></span><span id="rfc.iref.g.22"></span> <a href="#header.accept-charset" class="smpl">Accept-Charset</a> = "Accept-Charset" ":" <a href="#core.rules" class="smpl">OWS</a>
<a href="#header.accept-charset" class="smpl">Accept-Charset-v</a>
<a href="#header.accept-charset" class="smpl">Accept-Charset-v</a> = 1#( ( <a href="#rule.charset" class="smpl">charset</a> / "*" )
<div id="rfc.figure.u.21"></div><pre class="text"> Accept-Charset: iso-8859-5, unicode-1-1;q=0.8
<p id="rfc.section.5.3.p.1">The request-header field "Accept-Encoding" is similar to Accept, but restricts the content-codings (<a href="#content.codings" title="Content Codings">Section&nbsp;2.2</a>) that are acceptable in the response.
<div id="rfc.figure.u.22"></div><pre class="inline"><span id="rfc.iref.g.23"></span><span id="rfc.iref.g.24"></span><span id="rfc.iref.g.25"></span> <a href="#header.accept-encoding" class="smpl">Accept-Encoding</a> = "Accept-Encoding" ":" <a href="#core.rules" class="smpl">OWS</a>
<a href="#header.accept-encoding" class="smpl">Accept-Encoding-v</a>
<a href="#header.accept-encoding" class="smpl">Accept-Encoding-v</a> =
#( <a href="#header.accept-encoding" class="smpl">codings</a> [ <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> "q=" <a href="#abnf.dependencies" class="smpl">qvalue</a> ] )
</pre><p id="rfc.section.5.3.p.3">Each codings value <em class="bcp14">MAY</em> be given an associated quality value which represents the preference for that encoding. The default value is q=1.
<p id="rfc.section.5.3.p.4">Examples of its use are:</p>
<div id="rfc.figure.u.23"></div><pre class="text"> Accept-Encoding: compress, gzip
</pre><p id="rfc.section.5.3.p.6">A server tests whether a content-coding is acceptable, according to an Accept-Encoding field, using these rules: </p>
is accompanied by a qvalue of 0. (As defined in <a href="p1-messaging.html#quality.values" title="Quality Values">Section 3.5</a> of <a href="#Part1" id="rfc.xref.Part1.15"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, a qvalue of 0 means "not acceptable.")
<p id="rfc.section.5.3.p.7">If an Accept-Encoding field is present in a request, and if the server cannot send a response which is acceptable according
<p id="rfc.section.5.3.p.8">If no Accept-Encoding field is present in a request, the server <em class="bcp14">MAY</em> assume that the client will accept any content coding. In this case, if "identity" is one of the available content-codings,
<p id="rfc.section.5.4.p.1">The request-header field "Accept-Language" is similar to Accept, but restricts the set of natural languages that are preferred
as a response to the request. Language tags are defined in <a href="#language.tags" title="Language Tags">Section&nbsp;2.4</a>.
<div id="rfc.figure.u.24"></div><pre class="inline"><span id="rfc.iref.g.26"></span><span id="rfc.iref.g.27"></span><span id="rfc.iref.g.28"></span> <a href="#header.accept-language" class="smpl">Accept-Language</a> = "Accept-Language" ":" <a href="#core.rules" class="smpl">OWS</a>
<a href="#header.accept-language" class="smpl">Accept-Language-v</a>
<a href="#header.accept-language" class="smpl">Accept-Language-v</a> =
</pre><p id="rfc.section.5.4.p.3">Each language-range can be given an associated quality value which represents an estimate of the user's preference for the
<div id="rfc.figure.u.25"></div><pre class="text"> Accept-Language: da, en-gb;q=0.8, en;q=0.7
</pre><p id="rfc.section.5.4.p.5">would mean: "I prefer Danish, but will accept British English and other types of English."</p>
<p id="rfc.section.5.4.p.6">For matching, the "Basic Filtering" matching scheme, defined in <a href="http://tools.ietf.org/html/rfc4647#section-3.3.1">Section 3.3.1</a> of <a href="#RFC4647" id="rfc.xref.RFC4647.2"><cite title="Matching of Language Tags">[RFC4647]</cite></a>, is used:
<blockquote id="rfc.section.5.4.p.7" cite="http://tools.ietf.org/html/rfc4647#section-3.3.1">
<p>A language range matches a particular language tag if, in a case-insensitive comparison, it exactly equals the tag, or if
it exactly equals a prefix of the tag such that the first character following the prefix is "-".
<p id="rfc.section.5.4.p.8">The special range "*", if present in the Accept-Language field, matches every tag not matched by any other range present in
the Accept-Language field.
<p id="rfc.section.5.4.p.9">The language quality factor assigned to a language-tag by the Accept-Language field is the quality value of the longest language-range
<p id="rfc.section.5.4.p.10">It might be contrary to the privacy expectations of the user to send an Accept-Language header with the complete linguistic
<p id="rfc.section.5.4.p.11">As intelligibility is highly dependent on the individual user, it is recommended that client applications make the choice
<p id="rfc.section.5.5.p.1">The entity-header field "Content-Encoding" is used as a modifier to the media-type. When present, its value indicates what
additional content codings have been applied to the entity-body, and thus what decoding mechanisms must be applied in order
to obtain the media-type referenced by the Content-Type header field. Content-Encoding is primarily used to allow a document
to be compressed without losing the identity of its underlying media type.
<div id="rfc.figure.u.26"></div><pre class="inline"><span id="rfc.iref.g.29"></span><span id="rfc.iref.g.30"></span> <a href="#header.content-encoding" class="smpl">Content-Encoding</a> = "Content-Encoding" ":" <a href="#core.rules" class="smpl">OWS</a> <a href="#header.content-encoding" class="smpl">Content-Encoding-v</a>
<a href="#header.content-encoding" class="smpl">Content-Encoding-v</a> = 1#<a href="#content.codings" class="smpl">content-coding</a>
<div id="rfc.figure.u.27"></div><pre class="text"> Content-Encoding: gzip
</pre><p id="rfc.section.5.5.p.5">The content-coding is a characteristic of the entity identified by the request-target. Typically, the entity-body is stored
with this encoding and is only decoded before rendering or analogous usage. However, a non-transparent proxy <em class="bcp14">MAY</em> modify the content-coding if the new coding is known to be acceptable to the recipient, unless the "no-transform" cache-control
<p id="rfc.section.5.6.p.1">The entity-header field "Content-Language" describes the natural language(s) of the intended audience for the enclosed entity.
<div id="rfc.figure.u.28"></div><pre class="inline"><span id="rfc.iref.g.31"></span><span id="rfc.iref.g.32"></span> <a href="#header.content-language" class="smpl">Content-Language</a> = "Content-Language" ":" <a href="#core.rules" class="smpl">OWS</a> <a href="#header.content-language" class="smpl">Content-Language-v</a>
<a href="#header.content-language" class="smpl">Content-Language-v</a> = 1#<a href="#language.tags" class="smpl">language-tag</a>
</pre><p id="rfc.section.5.6.p.3">Language tags are defined in <a href="#language.tags" title="Language Tags">Section&nbsp;2.4</a>. The primary purpose of Content-Language is to allow a user to identify and differentiate entities according to the user's
<div id="rfc.figure.u.29"></div><pre class="text"> Content-Language: da
<div id="rfc.figure.u.30"></div><pre class="text"> Content-Language: mi, en
<p id="rfc.section.5.7.p.1">The entity-header field "Content-Location" <em class="bcp14">MAY</em> be used to supply the resource location for the entity enclosed in the message when that entity is accessible from a location
<div id="rfc.figure.u.31"></div><pre class="inline"><span id="rfc.iref.g.33"></span><span id="rfc.iref.g.34"></span> <a href="#header.content-location" class="smpl">Content-Location</a> = "Content-Location" ":" <a href="#core.rules" class="smpl">OWS</a>
<a href="#header.content-location" class="smpl">Content-Location-v</a>
<a href="#header.content-location" class="smpl">Content-Location-v</a> =
<a href="#abnf.dependencies" class="smpl">absolute-URI</a> / <a href="#abnf.dependencies" class="smpl">partial-URI</a>
the resource corresponding to this particular entity at the time of the request. Future requests <em class="bcp14">MAY</em> specify the Content-Location URI as the request-target if the desire is to identify the source of that particular entity.
entities retrieved from a single requested resource, as described in <a href="p6-cache.html#caching.negotiated.responses" title="Caching Negotiated Responses">Section 2.6</a> of <a href="#Part6" id="rfc.xref.Part6.4"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>.
<p id="rfc.section.5.7.p.6">If the Content-Location is a relative URI, the relative URI is interpreted relative to the request-target.</p>
<p id="rfc.section.5.8.p.1">The entity-header field "Content-MD5", as defined in <a href="#RFC1864" id="rfc.xref.RFC1864.1"><cite title="The Content-MD5 Header Field">[RFC1864]</cite></a>, is an MD5 digest of the entity-body for the purpose of providing an end-to-end message integrity check (MIC) of the entity-body.
<div id="rfc.figure.u.32"></div><pre class="inline"><span id="rfc.iref.g.35"></span><span id="rfc.iref.g.36"></span> <a href="#header.content-md5" class="smpl">Content-MD5</a> = "Content-MD5" ":" <a href="#core.rules" class="smpl">OWS</a> <a href="#header.content-md5" class="smpl">Content-MD5-v</a>
<a href="#header.content-md5" class="smpl">Content-MD5-v</a> = &lt;base64 of 128 bit MD5 digest as per <a href="#RFC1864" id="rfc.xref.RFC1864.2"><cite title="The Content-MD5 Header Field">[RFC1864]</cite></a>&gt;
<p id="rfc.section.5.9.p.1">The entity-header field "Content-Type" indicates the media type of the entity-body sent to the recipient or, in the case of
<div id="rfc.figure.u.33"></div><pre class="inline"><span id="rfc.iref.g.37"></span><span id="rfc.iref.g.38"></span> <a href="#header.content-type" class="smpl">Content-Type</a> = "Content-Type" ":" <a href="#core.rules" class="smpl">OWS</a> <a href="#header.content-type" class="smpl">Content-Type-v</a>
<a href="#header.content-type" class="smpl">Content-Type-v</a> = <a href="#media.types" class="smpl">media-type</a>
<div id="rfc.figure.u.34"></div><pre class="text"> Content-Type: text/html; charset=ISO-8859-4
<h2 id="rfc.section.6.1"><a href="#rfc.section.6.1">6.1</a>&nbsp;<a id="message.header.registration" href="#message.header.registration">Message Header Registration</a></h2>
<p id="rfc.section.6.1.p.1">The Message Header 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; should be updated with the permanent registrations below (see <a href="#RFC3864" id="rfc.xref.RFC3864.1"><cite title="Registration Procedures for Message Header Fields">[RFC3864]</cite></a>):
<td>Accept</td>
<td> <a href="#header.accept" id="rfc.xref.header.accept.3" title="Accept">Section&nbsp;5.1</a>
<td>Accept-Charset</td>
<td> <a href="#header.accept-charset" id="rfc.xref.header.accept-charset.2" title="Accept-Charset">Section&nbsp;5.2</a>
<td>Accept-Encoding</td>
<td> <a href="#header.accept-encoding" id="rfc.xref.header.accept-encoding.3" title="Accept-Encoding">Section&nbsp;5.3</a>
<td>Accept-Language</td>
<td> <a href="#header.accept-language" id="rfc.xref.header.accept-language.2" title="Accept-Language">Section&nbsp;5.4</a>
<td>Content-Disposition</td>
<td> <a href="#content-disposition" id="rfc.xref.content-disposition.1" title="Content-Disposition">Appendix&nbsp;B.1</a>
<td>Content-Encoding</td>
<td> <a href="#header.content-encoding" id="rfc.xref.header.content-encoding.4" title="Content-Encoding">Section&nbsp;5.5</a>
<td>Content-Language</td>
<td> <a href="#header.content-language" id="rfc.xref.header.content-language.2" title="Content-Language">Section&nbsp;5.6</a>
<td>Content-Location</td>
<td> <a href="#header.content-location" id="rfc.xref.header.content-location.2" title="Content-Location">Section&nbsp;5.7</a>
<td>Content-MD5</td>
<td> <a href="#header.content-md5" id="rfc.xref.header.content-md5.2" title="Content-MD5">Section&nbsp;5.8</a>
<td>Content-Type</td>
<td> <a href="#header.content-type" id="rfc.xref.header.content-type.3" title="Content-Type">Section&nbsp;5.9</a>
<td>MIME-Version</td>
<td> <a href="#mime-version" id="rfc.xref.mime-version.1" title="MIME-Version">Appendix&nbsp;A.1</a>
<p id="rfc.section.6.1.p.2">The change controller is: "IETF (iesg@ietf.org) - Internet Engineering Task Force".</p>
<p id="rfc.section.7.2.p.1"> <a href="#RFC2183" id="rfc.xref.RFC2183.1"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a>, from which the often implemented Content-Disposition (see <a href="#content-disposition" id="rfc.xref.content-disposition.2" title="Content-Disposition">Appendix&nbsp;B.1</a>) header in HTTP is derived, has a number of very serious security considerations. Content-Disposition is not part of the
HTTP standard, but since it is widely implemented, we are documenting its use and risks for implementors. See <a href="http://tools.ietf.org/html/rfc2183#section-5">Section 5</a> of <a href="#RFC2183" id="rfc.xref.RFC2183.2"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a> for details.
<td class="top"><a title="Day Software">Fielding, R., Ed.</a>, <a title="One Laptop per Child">Gettys, J.</a>, <a title="Hewlett-Packard Company">Mogul, J.</a>, <a title="Microsoft Corporation">Frystyk, H.</a>, <a title="Adobe Systems, Incorporated">Masinter, L.</a>, <a title="Microsoft Corporation">Leach, P.</a>, <a title="World Wide Web Consortium">Berners-Lee, T.</a>, <a title="World Wide Web Consortium">Lafon, Y., Ed.</a>, and <a title="greenbytes GmbH">J. F. Reschke, Ed.</a>, “<a href="http://tools.ietf.org/html/draft-ietf-httpbis-p1-messaging-latest">HTTP/1.1, part 1: URIs, Connections, and Message Parsing</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p1-messaging-latest (work in progress), March&nbsp;2009.
<td class="top"><a title="Day Software">Fielding, R., Ed.</a>, <a title="One Laptop per Child">Gettys, J.</a>, <a title="Hewlett-Packard Company">Mogul, J.</a>, <a title="Microsoft Corporation">Frystyk, H.</a>, <a title="Adobe Systems, Incorporated">Masinter, L.</a>, <a title="Microsoft Corporation">Leach, P.</a>, <a title="World Wide Web Consortium">Berners-Lee, T.</a>, <a title="World Wide Web Consortium">Lafon, Y., Ed.</a>, and <a title="greenbytes GmbH">J. F. Reschke, Ed.</a>, “<a href="http://tools.ietf.org/html/draft-ietf-httpbis-p2-semantics-latest">HTTP/1.1, part 2: Message Semantics</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p2-semantics-latest (work in progress), March&nbsp;2009.
<td class="top"><a title="Day Software">Fielding, R., Ed.</a>, <a title="One Laptop per Child">Gettys, J.</a>, <a title="Hewlett-Packard Company">Mogul, J.</a>, <a title="Microsoft Corporation">Frystyk, H.</a>, <a title="Adobe Systems, Incorporated">Masinter, L.</a>, <a title="Microsoft Corporation">Leach, P.</a>, <a title="World Wide Web Consortium">Berners-Lee, T.</a>, <a title="World Wide Web Consortium">Lafon, Y., Ed.</a>, and <a title="greenbytes GmbH">J. F. Reschke, Ed.</a>, “<a href="http://tools.ietf.org/html/draft-ietf-httpbis-p4-conditional-latest">HTTP/1.1, part 4: Conditional Requests</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p4-conditional-latest (work in progress), March&nbsp;2009.
<td class="top"><a title="Day Software">Fielding, R., Ed.</a>, <a title="One Laptop per Child">Gettys, J.</a>, <a title="Hewlett-Packard Company">Mogul, J.</a>, <a title="Microsoft Corporation">Frystyk, H.</a>, <a title="Adobe Systems, Incorporated">Masinter, L.</a>, <a title="Microsoft Corporation">Leach, P.</a>, <a title="World Wide Web Consortium">Berners-Lee, T.</a>, <a title="World Wide Web Consortium">Lafon, Y., Ed.</a>, and <a title="greenbytes GmbH">J. F. Reschke, Ed.</a>, “<a href="http://tools.ietf.org/html/draft-ietf-httpbis-p5-range-latest">HTTP/1.1, part 5: Range Requests and Partial Responses</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p5-range-latest (work in progress), March&nbsp;2009.
<td class="top"><a title="Day Software">Fielding, R., Ed.</a>, <a title="One Laptop per Child">Gettys, J.</a>, <a title="Hewlett-Packard Company">Mogul, J.</a>, <a title="Microsoft Corporation">Frystyk, H.</a>, <a title="Adobe Systems, Incorporated">Masinter, L.</a>, <a title="Microsoft Corporation">Leach, P.</a>, <a title="World Wide Web Consortium">Berners-Lee, T.</a>, <a title="World Wide Web Consortium">Lafon, Y., Ed.</a>, and <a title="greenbytes GmbH">J. F. Reschke, Ed.</a>, “<a href="http://tools.ietf.org/html/draft-ietf-httpbis-p6-cache-latest">HTTP/1.1, part 6: Caching</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p6-cache-latest (work in progress), March&nbsp;2009.
<td class="top"><a title="Aladdin Enterprises">Deutsch, L.P.</a> and J-L. Gailly, “<a href="http://tools.ietf.org/html/rfc1950">ZLIB Compressed Data Format Specification version 3.3</a>”, RFC&nbsp;1950, May&nbsp;1996.<br>RFC 1950 is an Informational RFC, thus it may be less stable than this specification. On the other hand, this downward reference
<td class="top"><a title="Aladdin Enterprises">Deutsch, P.</a>, “<a href="http://tools.ietf.org/html/rfc1951">DEFLATE Compressed Data Format Specification version 1.3</a>”, RFC&nbsp;1951, May&nbsp;1996.<br>RFC 1951 is an Informational RFC, thus it may be less stable than this specification. On the other hand, this downward reference
<td class="top"><a title="Aladdin Enterprises">Deutsch, P.</a>, <a>Gailly, J-L.</a>, <a>Adler, M.</a>, <a>Deutsch, L.P.</a>, and <a>G. Randers-Pehrson</a>, “<a href="http://tools.ietf.org/html/rfc1952">GZIP file format specification version 4.3</a>”, RFC&nbsp;1952, May&nbsp;1996.<br>RFC 1952 is an Informational RFC, thus it may be less stable than this specification. On the other hand, this downward reference
<td class="top"><a title="Yahoo! Inc.">Phillips, A., Ed.</a> and <a title="Google">M. Davis, Ed.</a>, “<a href="http://tools.ietf.org/html/rfc4647">Matching of Language Tags</a>”, BCP&nbsp;47, RFC&nbsp;4647, September&nbsp;2006.
<td class="top"><a>Klensin, J.</a> and <a title="MIT">S. Hartman</a>, “<a href="http://tools.ietf.org/html/rfc4897">Handling Normative References to Standards-Track Documents</a>”, BCP&nbsp;97, RFC&nbsp;4897, June&nbsp;2007.
<td class="top"><a title="Xerox Palo Alto Research Center">Masinter, L.</a>, “<a href="http://tools.ietf.org/html/rfc2388">Returning Values from Forms: multipart/form-data</a>”, RFC&nbsp;2388, August&nbsp;1998.
<td class="top"><a title="Stockholm University and KTH">Palme, F.</a>, <a title="Microsoft Corporation">Hopmann, A.</a>, <a title="Lotus Development Corporation">Shelness, N.</a>, and <a>E. Stefferud</a>, “<a href="http://tools.ietf.org/html/rfc2557">MIME Encapsulation of Aggregate Documents, such as HTML (MHTML)</a>”, RFC&nbsp;2557, March&nbsp;1999.
<td class="top"><a title="Alis Technologies">Yergeau, F.</a>, “<a href="http://tools.ietf.org/html/rfc3629">UTF-8, a transformation format of ISO 10646</a>”, RFC&nbsp;3629, STD&nbsp;63, November&nbsp;2003.
<td class="top"><a title="Sun Microsystems">Freed, N.</a> and <a>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.
<p id="rfc.section.A.p.1">HTTP/1.1 uses many of the constructs defined for Internet Mail (<a href="#RFC5322" id="rfc.xref.RFC5322.1"><cite title="Internet Message Format">[RFC5322]</cite></a>) and the Multipurpose Internet Mail Extensions (MIME <a href="#RFC2045" id="rfc.xref.RFC2045.1"><cite title="Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies">[RFC2045]</cite></a>) to allow entities to be transmitted in an open variety of representations and with extensible mechanisms. However, RFC 2045
defined in <a href="#RFC2045" id="rfc.xref.RFC2045.2"><cite title="Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies">[RFC2045]</cite></a>). Proxies/gateways are responsible for ensuring full compliance (where possible) when exporting HTTP messages to strict MIME
<div id="rfc.figure.u.35"></div><pre class="inline"><span id="rfc.iref.g.39"></span><span id="rfc.iref.g.40"></span> <a href="#mime-version" class="smpl">MIME-Version</a> = "MIME-Version" ":" <a href="#core.rules" class="smpl">OWS</a> <a href="#mime-version" class="smpl">MIME-Version-v</a>
<a href="#mime-version" class="smpl">MIME-Version-v</a> = 1*<a href="#notation" class="smpl">DIGIT</a> "." 1*<a href="#notation" class="smpl">DIGIT</a>
<p id="rfc.section.A.2.p.1"> <a href="#RFC2045" id="rfc.xref.RFC2045.3"><cite title="Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies">[RFC2045]</cite></a> requires that an Internet mail entity be converted to canonical form prior to being transferred, as described in <a href="http://tools.ietf.org/html/rfc2049#section-4">Section 4</a> of <a href="#RFC2049" id="rfc.xref.RFC2049.1"><cite title="Multipurpose Internet Mail Extensions (MIME) Part Five: Conformance Criteria and Examples">[RFC2049]</cite></a>. <a href="#canonicalization.and.text.defaults" title="Canonicalization and Text Defaults">Section&nbsp;2.3.1</a> of this document describes the forms allowed for subtypes of the "text" media type when transmitted over HTTP. <a href="#RFC2046" id="rfc.xref.RFC2046.3"><cite title="Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types">[RFC2046]</cite></a> requires that content with a type of "text" represent line breaks as CRLF and forbids the use of CR or LF outside of line
<p id="rfc.section.A.3.p.1">HTTP/1.1 uses a restricted set of date formats (<a href="p1-messaging.html#full.date" title="Full Date">Section 3.2.1</a> of <a href="#Part1" id="rfc.xref.Part1.16"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) to simplify the process of date comparison. Proxies and gateways from other protocols <em class="bcp14">SHOULD</em> ensure that any Date header field present in a message conforms to one of the HTTP/1.1 formats and rewrite the date if necessary.
<p id="rfc.section.A.4.p.1">RFC 2045 does not include any concept equivalent to HTTP/1.1's Content-Encoding header field. Since this acts as a modifier
<p id="rfc.section.A.5.p.1">HTTP does not use the Content-Transfer-Encoding field of RFC 2045. Proxies and gateways from MIME-compliant protocols to HTTP <em class="bcp14">MUST</em> remove any Content-Transfer-Encoding prior to delivering the response message to an HTTP client.
<p id="rfc.section.A.6.p.1">HTTP/1.1 introduces the Transfer-Encoding header field (<a href="p1-messaging.html#header.transfer-encoding" title="Transfer-Encoding">Section 8.7</a> of <a href="#Part1" id="rfc.xref.Part1.17"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). Proxies/gateways <em class="bcp14">MUST</em> remove any transfer-coding prior to forwarding a message via a MIME-compliant protocol.
<p id="rfc.section.A.7.p.1">HTTP implementations which share code with MHTML <a href="#RFC2557" id="rfc.xref.RFC2557.1"><cite title="MIME Encapsulation of Aggregate Documents, such as HTML (MHTML)">[RFC2557]</cite></a> implementations need to be aware of MIME line length limitations. Since HTTP does not have this limitation, HTTP does not
<p id="rfc.section.B.p.2">A number of other headers, such as Content-Disposition and Title, from SMTP and MIME are also often implemented (see <a href="#RFC2076" id="rfc.xref.RFC2076.1"><cite title="Common Internet Message Headers">[RFC2076]</cite></a>).
<div id="rfc.iref.h.11"></div>
in <a href="#RFC2183" id="rfc.xref.RFC2183.3"><cite title="Communicating Presentation Information in Internet Messages: The Content-Disposition Header Field">[RFC2183]</cite></a>.
<div id="rfc.figure.u.36"></div><pre class="inline"><span id="rfc.iref.g.41"></span><span id="rfc.iref.g.42"></span><span id="rfc.iref.g.43"></span><span id="rfc.iref.g.44"></span><span id="rfc.iref.g.45"></span><span id="rfc.iref.g.46"></span><span id="rfc.iref.g.47"></span> <a href="#content-disposition" class="smpl">content-disposition</a> = "Content-Disposition" ":" <a href="#core.rules" class="smpl">OWS</a>
<a href="#content-disposition" class="smpl">content-disposition-v</a>
<a href="#content-disposition" class="smpl">content-disposition-v</a> = <a href="#content-disposition" class="smpl">disposition-type</a>
*( <a href="#core.rules" class="smpl">OWS</a> ";" <a href="#core.rules" class="smpl">OWS</a> <a href="#content-disposition" class="smpl">disposition-parm</a> )
<a href="#content-disposition" class="smpl">disposition-type</a> = "attachment" / <a href="#content-disposition" class="smpl">disp-extension-token</a>
<a href="#content-disposition" class="smpl">disposition-parm</a> = <a href="#content-disposition" class="smpl">filename-parm</a> / <a href="#content-disposition" class="smpl">disp-extension-parm</a>
<a href="#content-disposition" class="smpl">filename-parm</a> = "filename" "=" <a href="#core.rules" class="smpl">quoted-string</a>
<a href="#content-disposition" class="smpl">disp-extension-token</a> = <a href="#core.rules" class="smpl">token</a>
<a href="#content-disposition" class="smpl">disp-extension-parm</a> = <a href="#core.rules" class="smpl">token</a> "=" ( <a href="#core.rules" class="smpl">token</a> / <a href="#core.rules" class="smpl">quoted-string</a> )
<div id="rfc.figure.u.37"></div><pre class="text"> Content-Disposition: attachment; filename="fname.ext"
<h1 id="rfc.section.C"><a href="#rfc.section.C">C.</a>&nbsp;<a id="compatibility" href="#compatibility">Compatibility with Previous Versions</a></h1>
<h2 id="rfc.section.C.1"><a href="#rfc.section.C.1">C.1</a>&nbsp;<a id="changes.from.rfc.2068" href="#changes.from.rfc.2068">Changes from RFC 2068</a></h2>
<p id="rfc.section.C.1.p.1">Transfer-coding and message lengths all interact in ways that required fixing exactly when chunked encoding is used (to allow
computed. (<a href="#entity.length" title="Entity Length">Section&nbsp;3.2.2</a>, see also <a href="#Part1" id="rfc.xref.Part1.18"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="#Part5" id="rfc.xref.Part5.4"><cite title="HTTP/1.1, part 5: Range Requests and Partial Responses">[Part5]</cite></a> and <a href="#Part6" id="rfc.xref.Part6.5"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>).
<p id="rfc.section.C.1.p.2">Charset wildcarding is introduced to avoid explosion of character set names in accept headers. (<a href="#header.accept-charset" id="rfc.xref.header.accept-charset.3" title="Accept-Charset">Section&nbsp;5.2</a>)
<p id="rfc.section.C.1.p.3">Content-Base was deleted from the specification: it was not implemented widely, and there is no simple, safe way to introduce
it without a robust extension mechanism. In addition, it is used in a similar, but not identical fashion in MHTML <a href="#RFC2557" id="rfc.xref.RFC2557.2"><cite title="MIME Encapsulation of Aggregate Documents, such as HTML (MHTML)">[RFC2557]</cite></a>.
<p id="rfc.section.C.1.p.4">A content-coding of "identity" was introduced, to solve problems discovered in caching. (<a href="#content.codings" title="Content Codings">Section&nbsp;2.2</a>)
<p id="rfc.section.C.1.p.5">The Alternates<span id="rfc.iref.a.5"></span><span id="rfc.iref.h.12"></span>, Content-Version<span id="rfc.iref.c.8"></span><span id="rfc.iref.h.13"></span>, Derived-From<span id="rfc.iref.d.2"></span><span id="rfc.iref.h.14"></span>, Link<span id="rfc.iref.l.1"></span><span id="rfc.iref.h.15"></span>, URI<span id="rfc.iref.u.1"></span><span id="rfc.iref.h.16"></span>, Public<span id="rfc.iref.p.1"></span><span id="rfc.iref.h.17"></span> and Content-Base<span id="rfc.iref.c.9"></span><span id="rfc.iref.h.18"></span> header fields were defined in previous versions of this specification, but not commonly implemented. See <a href="http://tools.ietf.org/html/rfc2068#section-19.6.2">Section 19.6.2</a> of <a href="#RFC2068" id="rfc.xref.RFC2068.5"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2068]</cite></a>.
<h2 id="rfc.section.C.2"><a href="#rfc.section.C.2">C.2</a>&nbsp;<a id="changes.from.rfc.2616" href="#changes.from.rfc.2616">Changes from RFC 2616</a></h2>
<p id="rfc.section.C.2.p.1">Clarify contexts that charset is used in. (<a href="#character.sets" title="Character Sets">Section&nbsp;2.1</a>)
<p id="rfc.section.C.2.p.2">Remove reference to non-existant identity transfer-coding value tokens. (<a href="#no.content-transfer-encoding" title="No Content-Transfer-Encoding">Appendix&nbsp;A.5</a>)
<div id="rfc.figure.u.38"></div> <pre class="inline"><a href="#header.accept" class="smpl">Accept</a> = "Accept:" OWS Accept-v
<a href="#header.accept-charset" class="smpl">Accept-Charset</a> = "Accept-Charset:" OWS Accept-Charset-v
<a href="#header.accept-charset" class="smpl">Accept-Charset-v</a> = *( "," OWS ) ( charset / "*" ) [ OWS ";" OWS "q="
<a href="#header.accept-encoding" class="smpl">Accept-Encoding</a> = "Accept-Encoding:" OWS Accept-Encoding-v
<a href="#header.accept-encoding" class="smpl">Accept-Encoding-v</a> = [ ( "," / ( codings [ OWS ";" OWS "q=" qvalue ] )
<a href="#header.accept-language" class="smpl">Accept-Language</a> = "Accept-Language:" OWS Accept-Language-v
<a href="#header.accept-language" class="smpl">Accept-Language-v</a> = *( "," OWS ) language-range [ OWS ";" OWS "q="
<a href="#header.accept" class="smpl">Accept-v</a> = [ ( "," / ( media-range [ accept-params ] ) ) *( OWS "," [
<a href="#header.content-encoding" class="smpl">Content-Encoding</a> = "Content-Encoding:" OWS Content-Encoding-v
<a href="#header.content-encoding" class="smpl">Content-Encoding-v</a> = *( "," OWS ) content-coding *( OWS "," [ OWS
<a href="#header.content-language" class="smpl">Content-Language</a> = "Content-Language:" OWS Content-Language-v
<a href="#header.content-language" class="smpl">Content-Language-v</a> = *( "," OWS ) language-tag *( OWS "," [ OWS
<a href="#abnf.dependencies" class="smpl">Content-Length</a> = &lt;Content-Length, defined in [Part1], Section 8.2&gt;
<a href="#header.content-location" class="smpl">Content-Location</a> = "Content-Location:" OWS Content-Location-v
<a href="#header.content-location" class="smpl">Content-Location-v</a> = absolute-URI / partial-URI
<a href="#header.content-md5" class="smpl">Content-MD5</a> = "Content-MD5:" OWS Content-MD5-v
<a href="#header.content-md5" class="smpl">Content-MD5-v</a> = &lt;base64 of 128 bit MD5 digest as per [RFC1864]&gt;
<a href="#abnf.dependencies" class="smpl">Content-Range</a> = &lt;Content-Range, defined in [Part5], Section 5.2&gt;
<a href="#header.content-type" class="smpl">Content-Type</a> = "Content-Type:" OWS Content-Type-v
<a href="#header.content-type" class="smpl">Content-Type-v</a> = media-type
<a href="#abnf.dependencies" class="smpl">Expires</a> = &lt;Expires, defined in [Part6], Section 3.3&gt;
<a href="#abnf.dependencies" class="smpl">Last-Modified</a> = &lt;Last-Modified, defined in [Part4], Section 6.6&gt;
<a href="#mime-version" class="smpl">MIME-Version</a> = "MIME-Version:" OWS MIME-Version-v
<a href="#mime-version" class="smpl">MIME-Version-v</a> = 1*DIGIT "." 1*DIGIT
<a href="#abnf.dependencies" class="smpl">absolute-URI</a> = &lt;absolute-URI, defined in [Part1], Section 2.1&gt;
<a href="#header.accept" class="smpl">accept-ext</a> = OWS ";" OWS token [ "=" ( token / quoted-string ) ]
<a href="#content-disposition" class="smpl">content-disposition</a> = "Content-Disposition:" OWS
<a href="#content-disposition" class="smpl">content-disposition-v</a> = disposition-type *( OWS ";" OWS
<a href="#content-disposition" class="smpl">disp-extension-parm</a> = token "=" ( token / quoted-string )
<a href="#content-disposition" class="smpl">disp-extension-token</a> = token
<a href="#content-disposition" class="smpl">disposition-parm</a> = filename-parm / disp-extension-parm
<a href="#content-disposition" class="smpl">disposition-type</a> = "attachment" / disp-extension-token
<a href="#entity.body" class="smpl">entity-body</a> = *OCTET
<a href="#entity.header.fields" class="smpl">entity-header</a> = Content-Encoding / Content-Language / Content-Length
<a href="#entity.header.fields" class="smpl">extension-header</a> = message-header
<a href="#content-disposition" class="smpl">filename-parm</a> = "filename=" quoted-string
<a href="#language.tags" class="smpl">language-tag</a> = primary-tag *( "-" subtag )
<a href="#abnf.dependencies" class="smpl">message-header</a> = &lt;message-header, defined in [Part1], Section 4.2&gt;
<a href="#abnf.dependencies" class="smpl">partial-URI</a> = &lt;partial-URI, defined in [Part1], Section 2.1&gt;
<a href="#language.tags" class="smpl">primary-tag</a> = 1*8ALPHA
<a href="#core.rules" class="smpl">quoted-string</a> = &lt;quoted-string, defined in [Part1], Section 1.2.2&gt;
<a href="#abnf.dependencies" class="smpl">qvalue</a> = &lt;qvalue, defined in [Part1], Section 3.5&gt;
<a href="#language.tags" class="smpl">subtag</a> = 1*8ALPHA
<a href="#rule.parameter" class="smpl">value</a> = token / quoted-string
</pre> <div id="rfc.figure.u.39"></div>
<h2 id="rfc.section.E.1"><a href="#rfc.section.E.1">E.1</a>&nbsp;Since RFC2616
<p id="rfc.section.E.1.p.1">Extracted relevant partitions from <a href="#RFC2616" id="rfc.xref.RFC2616.2"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>.
<p id="rfc.section.E.4.p.2">Ongoing work on IANA Message Header Registration (&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/40">http://tools.ietf.org/wg/httpbis/trac/ticket/40</a>&gt;):
<li> &lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/68">http://tools.ietf.org/wg/httpbis/trac/ticket/68</a>&gt;: "Encoding References Normative" -- rephrase the annotation and reference <a href="#BCP97" id="rfc.xref.BCP97.4"><cite title="Handling Normative References to Standards-Track Documents">[BCP97]</cite></a>.
<p class="noprint"><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.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.P">P</a> <a href="#rfc.index.R">R</a> <a href="#rfc.index.U">U</a>
<li class="indline1">Accept header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.accept.1">2.3</a>, <a class="iref" href="#rfc.xref.header.accept.2">4.1</a>, <a class="iref" href="#rfc.iref.a.1"><b>5.1</b></a>, <a class="iref" href="#rfc.xref.header.accept.3">6.1</a></li>
<li class="indline1">Accept-Charset header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.accept-charset.1">4.1</a>, <a class="iref" href="#rfc.iref.a.2"><b>5.2</b></a>, <a class="iref" href="#rfc.xref.header.accept-charset.2">6.1</a>, <a class="iref" href="#rfc.xref.header.accept-charset.3">C.1</a></li>
<li class="indline1">Accept-Encoding header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.accept-encoding.1">2.2</a>, <a class="iref" href="#rfc.xref.header.accept-encoding.2">4.1</a>, <a class="iref" href="#rfc.iref.a.3"><b>5.3</b></a>, <a class="iref" href="#rfc.xref.header.accept-encoding.3">6.1</a></li>
<li class="indline1">Accept-Language header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.accept-language.1">4.1</a>, <a class="iref" href="#rfc.iref.a.4"><b>5.4</b></a>, <a class="iref" href="#rfc.xref.header.accept-language.2">6.1</a></li>
<li class="indline1">Alternates header&nbsp;&nbsp;<a class="iref" href="#rfc.iref.a.5"><b>C.1</b></a></li>
<li class="indline0"><a id="rfc.index.B" href="#rfc.index.B"><b>B</b></a><ul class="ind">
<li class="indline1"><em>BCP97</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.BCP97.1">9.1</a>, <a class="iref" href="#rfc.xref.BCP97.2">9.1</a>, <a class="iref" href="#rfc.xref.BCP97.3">9.1</a>, <a class="iref" href="#BCP97"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.BCP97.4">E.5</a></li>
<li class="indline1">Content-Base header&nbsp;&nbsp;<a class="iref" href="#rfc.iref.c.9"><b>C.1</b></a></li>
<li class="indline1">Content-Disposition header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.content-disposition.1">6.1</a>, <a class="iref" href="#rfc.xref.content-disposition.2">7.2</a>, <a class="iref" href="#rfc.iref.c.7"><b>B.1</b></a>, <a class="iref" href="#rfc.extref.c.32">B.1</a>, <a class="iref" href="#rfc.extref.c.50">D</a></li>
<li class="indline1">Content-Encoding header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-encoding.1">2.2</a>, <a class="iref" href="#rfc.xref.header.content-encoding.2">3.1</a>, <a class="iref" href="#rfc.iref.c.2"><b>5.5</b></a>, <a class="iref" href="#rfc.xref.header.content-encoding.3">5.5</a>, <a class="iref" href="#rfc.xref.header.content-encoding.4">6.1</a></li>
<li class="indline1">Content-Language header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-language.1">3.1</a>, <a class="iref" href="#rfc.iref.c.3"><b>5.6</b></a>, <a class="iref" href="#rfc.xref.header.content-language.2">6.1</a></li>
<li class="indline1">Content-Location header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-location.1">3.1</a>, <a class="iref" href="#rfc.iref.c.4"><b>5.7</b></a>, <a class="iref" href="#rfc.xref.header.content-location.2">6.1</a></li>
<li class="indline1">Content-MD5 header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-md5.1">3.1</a>, <a class="iref" href="#rfc.iref.c.5"><b>5.8</b></a>, <a class="iref" href="#rfc.xref.header.content-md5.2">6.1</a></li>
<li class="indline1">Content-Type header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-type.1">2.3</a>, <a class="iref" href="#rfc.xref.header.content-type.2">3.1</a>, <a class="iref" href="#rfc.iref.c.6"><b>5.9</b></a>, <a class="iref" href="#rfc.xref.header.content-type.3">6.1</a></li>
<li class="indline1">Content-Version header&nbsp;&nbsp;<a class="iref" href="#rfc.iref.c.8"><b>C.1</b></a></li>
<li class="indline1">Derived-From header&nbsp;&nbsp;<a class="iref" href="#rfc.iref.d.2"><b>C.1</b></a></li>
<li class="indline1"><tt>Accept</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.16"><b>5.1</b></a></li>
<li class="indline1"><tt>Accept-Charset-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.22"><b>5.2</b></a></li>
<li class="indline1"><tt>Accept-Encoding</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.23"><b>5.3</b></a></li>
<li class="indline1"><tt>Accept-Encoding-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.24"><b>5.3</b></a></li>
<li class="indline1"><tt>accept-ext</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.20"><b>5.1</b></a></li>
<li class="indline1"><tt>Accept-Language</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.26"><b>5.4</b></a></li>
<li class="indline1"><tt>Accept-Language-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.27"><b>5.4</b></a></li>
<li class="indline1"><tt>Accept-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.17"><b>5.1</b></a></li>
<li class="indline1"><tt>codings</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.25"><b>5.3</b></a></li>
<li class="indline1"><tt>content-disposition</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.41"><b>B.1</b></a></li>
<li class="indline1"><tt>content-disposition-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.42"><b>B.1</b></a></li>
<li class="indline1"><tt>Content-Encoding</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.29"><b>5.5</b></a></li>
<li class="indline1"><tt>Content-Encoding-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.30"><b>5.5</b></a></li>
<li class="indline1"><tt>Content-Language</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.31"><b>5.6</b></a></li>
<li class="indline1"><tt>Content-Language-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.32"><b>5.6</b></a></li>
<li class="indline1"><tt>Content-Location</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.33"><b>5.7</b></a></li>
<li class="indline1"><tt>Content-Location-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.34"><b>5.7</b></a></li>
<li class="indline1"><tt>Content-MD5</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.35"><b>5.8</b></a></li>
<li class="indline1"><tt>Content-MD5-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.36"><b>5.8</b></a></li>
<li class="indline1"><tt>Content-Type</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.37"><b>5.9</b></a></li>
<li class="indline1"><tt>Content-Type-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.38"><b>5.9</b></a></li>
<li class="indline1"><tt>disp-extension-parm</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.47"><b>B.1</b></a></li>
<li class="indline1"><tt>disp-extension-token</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.46"><b>B.1</b></a></li>
<li class="indline1"><tt>disposition-parm</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.44"><b>B.1</b></a></li>
<li class="indline1"><tt>disposition-type</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.43"><b>B.1</b></a></li>
<li class="indline1"><tt>entity-body</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.15"><b>3.2</b></a></li>
<li class="indline1"><tt>entity-header</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.13"><b>3.1</b></a></li>
<li class="indline1"><tt>extension-header</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.14"><b>3.1</b></a></li>
<li class="indline1"><tt>filename-parm</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.45"><b>B.1</b></a></li>
<li class="indline1"><tt>language-range</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.28"><b>5.4</b></a></li>
<li class="indline1"><tt>language-tag</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.10"><b>2.4</b></a></li>
<li class="indline1"><tt>MIME-Version</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.39"><b>A.1</b></a></li>
<li class="indline1"><tt>MIME-Version-v</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.40"><b>A.1</b></a></li>
<li class="indline1"><tt>primary-tag</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.11"><b>2.4</b></a></li>
<li class="indline1"><tt>subtag</tt>&nbsp;&nbsp;<a class="iref" href="#rfc.iref.g.12"><b>2.4</b></a></li>
<li class="indline1">Accept&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.accept.1">2.3</a>, <a class="iref" href="#rfc.xref.header.accept.2">4.1</a>, <a class="iref" href="#rfc.iref.h.1"><b>5.1</b></a>, <a class="iref" href="#rfc.xref.header.accept.3">6.1</a></li>
<li class="indline1">Accept-Charset&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.accept-charset.1">4.1</a>, <a class="iref" href="#rfc.iref.h.2"><b>5.2</b></a>, <a class="iref" href="#rfc.xref.header.accept-charset.2">6.1</a>, <a class="iref" href="#rfc.xref.header.accept-charset.3">C.1</a></li>
<li class="indline1">Accept-Encoding&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.accept-encoding.1">2.2</a>, <a class="iref" href="#rfc.xref.header.accept-encoding.2">4.1</a>, <a class="iref" href="#rfc.iref.h.3"><b>5.3</b></a>, <a class="iref" href="#rfc.xref.header.accept-encoding.3">6.1</a></li>
<li class="indline1">Accept-Language&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.accept-language.1">4.1</a>, <a class="iref" href="#rfc.iref.h.4"><b>5.4</b></a>, <a class="iref" href="#rfc.xref.header.accept-language.2">6.1</a></li>
<li class="indline1">Alternate&nbsp;&nbsp;<a class="iref" href="#rfc.iref.h.12"><b>C.1</b></a></li>
<li class="indline1">Content-Base&nbsp;&nbsp;<a class="iref" href="#rfc.iref.h.18"><b>C.1</b></a></li>
<li class="indline1">Content-Disposition&nbsp;&nbsp;<a class="iref" href="#rfc.xref.content-disposition.1">6.1</a>, <a class="iref" href="#rfc.xref.content-disposition.2">7.2</a>, <a class="iref" href="#rfc.iref.h.11"><b>B.1</b></a>, <a class="iref" href="#rfc.extref.c.32">B.1</a>, <a class="iref" href="#rfc.extref.c.50">D</a></li>
<li class="indline1">Content-Encoding&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-encoding.1">2.2</a>, <a class="iref" href="#rfc.xref.header.content-encoding.2">3.1</a>, <a class="iref" href="#rfc.iref.h.5"><b>5.5</b></a>, <a class="iref" href="#rfc.xref.header.content-encoding.3">5.5</a>, <a class="iref" href="#rfc.xref.header.content-encoding.4">6.1</a></li>
<li class="indline1">Content-Language&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-language.1">3.1</a>, <a class="iref" href="#rfc.iref.h.6"><b>5.6</b></a>, <a class="iref" href="#rfc.xref.header.content-language.2">6.1</a></li>
<li class="indline1">Content-Location&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-location.1">3.1</a>, <a class="iref" href="#rfc.iref.h.7"><b>5.7</b></a>, <a class="iref" href="#rfc.xref.header.content-location.2">6.1</a></li>
<li class="indline1">Content-MD5&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-md5.1">3.1</a>, <a class="iref" href="#rfc.iref.h.8"><b>5.8</b></a>, <a class="iref" href="#rfc.xref.header.content-md5.2">6.1</a></li>
<li class="indline1">Content-Type&nbsp;&nbsp;<a class="iref" href="#rfc.xref.header.content-type.1">2.3</a>, <a class="iref" href="#rfc.xref.header.content-type.2">3.1</a>, <a class="iref" href="#rfc.iref.h.9"><b>5.9</b></a>, <a class="iref" href="#rfc.xref.header.content-type.3">6.1</a></li>
<li class="indline1">Content-Version&nbsp;&nbsp;<a class="iref" href="#rfc.iref.h.13"><b>C.1</b></a></li>
<li class="indline1">Derived-From&nbsp;&nbsp;<a class="iref" href="#rfc.iref.h.14"><b>C.1</b></a></li>
<li class="indline1">Link&nbsp;&nbsp;<a class="iref" href="#rfc.iref.h.15"><b>C.1</b></a></li>
<li class="indline1">MIME-Version&nbsp;&nbsp;<a class="iref" href="#rfc.xref.mime-version.1">6.1</a>, <a class="iref" href="#rfc.iref.h.10"><b>A.1</b></a></li>
<li class="indline1">Public&nbsp;&nbsp;<a class="iref" href="#rfc.iref.h.17"><b>C.1</b></a></li>
<li class="indline1">URI&nbsp;&nbsp;<a class="iref" href="#rfc.iref.h.16"><b>C.1</b></a></li>
<li class="indline1"><em>ISO-8859-1</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.ISO-8859-1.1">2.1.1</a>, <a class="iref" href="#ISO-8859-1"><b>9.1</b></a></li>
<li class="indline1">Link header&nbsp;&nbsp;<a class="iref" href="#rfc.iref.l.1"><b>C.1</b></a></li>
<li class="indline1">MIME-Version header&nbsp;&nbsp;<a class="iref" href="#rfc.xref.mime-version.1">6.1</a>, <a class="iref" href="#rfc.iref.m.1"><b>A.1</b></a></li>
<li class="indline1"><em>Part1</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.1">1.2</a>, <a class="iref" href="#rfc.xref.Part1.2">1.2.1</a>, <a class="iref" href="#rfc.xref.Part1.3">1.2.1</a>, <a class="iref" href="#rfc.xref.Part1.4">1.2.1</a>, <a class="iref" href="#rfc.xref.Part1.5">1.2.1</a>, <a class="iref" href="#rfc.xref.Part1.6">1.2.2</a>, <a class="iref" href="#rfc.xref.Part1.7">1.2.2</a>, <a class="iref" href="#rfc.xref.Part1.8">1.2.2</a>, <a class="iref" href="#rfc.xref.Part1.9">1.2.2</a>, <a class="iref" href="#rfc.xref.Part1.10">1.2.2</a>, <a class="iref" href="#rfc.xref.Part1.11">3.1</a>, <a class="iref" href="#rfc.xref.Part1.12">3.2</a>, <a class="iref" href="#rfc.xref.Part1.13">3.2.2</a>, <a class="iref" href="#rfc.xref.Part1.14">5.1</a>, <a class="iref" href="#rfc.xref.Part1.15">5.3</a>, <a class="iref" href="#Part1"><b>9.1</b></a>, <a class="iref" href="#rfc.xref.Part1.16">A.3</a>, <a class="iref" href="#rfc.xref.Part1.17">A.6</a>, <a class="iref" href="#rfc.xref.Part1.18">C.1</a><ul class="ind">
<li class="indline1"><em>Section 1.2.2</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.2">1.2.1</a>, <a class="iref" href="#rfc.xref.Part1.3">1.2.1</a>, <a class="iref" href="#rfc.xref.Part1.4">1.2.1</a>, <a class="iref" href="#rfc.xref.Part1.5">1.2.1</a></li>
<li class="indline1"><em>Section 2.1</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.6">1.2.2</a>, <a class="iref" href="#rfc.xref.Part1.9">1.2.2</a></li>
<li class="indline1"><em>Section 3.2.1</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.16">A.3</a></li>
<li class="indline1"><em>Section 3.5</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.10">1.2.2</a>, <a class="iref" href="#rfc.xref.Part1.14">5.1</a>, <a class="iref" href="#rfc.xref.Part1.15">5.3</a></li>
<li class="indline1"><em>Section 4.2</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.8">1.2.2</a></li>
<li class="indline1"><em>Section 4.3</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.12">3.2</a></li>
<li class="indline1"><em>Section 4.4</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.13">3.2.2</a></li>
<li class="indline1"><em>Section 8.2</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.7">1.2.2</a>, <a class="iref" href="#rfc.xref.Part1.11">3.1</a></li>
<li class="indline1"><em>Section 8.7</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part1.17">A.6</a></li>
<li class="indline1"><em>Part2</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part2.1">4.1</a>, <a class="iref" href="#Part2"><b>9.1</b></a><ul class="ind">
<li class="indline1"><em>Section 9.9</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part2.1">4.1</a></li>
<li class="indline1"><em>Part4</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part4.1">1.2.2</a>, <a class="iref" href="#rfc.xref.Part4.2">3.1</a>, <a class="iref" href="#Part4"><b>9.1</b></a><ul class="ind">
<li class="indline1"><em>Section 6.6</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part4.1">1.2.2</a>, <a class="iref" href="#rfc.xref.Part4.2">3.1</a></li>
<li class="indline1"><em>Part5</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part5.1">1.2.2</a>, <a class="iref" href="#rfc.xref.Part5.2">2.3.2</a>, <a class="iref" href="#rfc.xref.Part5.3">3.1</a>, <a class="iref" href="#Part5"><b>9.1</b></a>, <a class="iref" href="#rfc.xref.Part5.4">C.1</a><ul class="ind">
<li class="indline1"><em>Section 5.2</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part5.1">1.2.2</a>, <a class="iref" href="#rfc.xref.Part5.3">3.1</a></li>
<li class="indline1"><em>Appendix A</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part5.2">2.3.2</a></li>
<li class="indline1"><em>Part6</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part6.1">1.2.2</a>, <a class="iref" href="#rfc.xref.Part6.2">3.1</a>, <a class="iref" href="#rfc.xref.Part6.3">4.1</a>, <a class="iref" href="#rfc.xref.Part6.4">5.7</a>, <a class="iref" href="#Part6"><b>9.1</b></a>, <a class="iref" href="#rfc.xref.Part6.5">C.1</a><ul class="ind">
<li class="indline1"><em>Section 2.6</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part6.4">5.7</a></li>
<li class="indline1"><em>Section 3.3</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part6.1">1.2.2</a>, <a class="iref" href="#rfc.xref.Part6.2">3.1</a></li>
<li class="indline1"><em>Section 3.5</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.Part6.3">4.1</a></li>
<li class="indline1">Public header&nbsp;&nbsp;<a class="iref" href="#rfc.iref.p.1"><b>C.1</b></a></li>
<li class="indline1"><em>RFC1766</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC1766.1">2.4</a>, <a class="iref" href="#RFC1766"><b>9.1</b></a></li>
<li class="indline1"><em>RFC1864</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC1864.1">5.8</a>, <a class="iref" href="#rfc.xref.RFC1864.2">5.8</a>, <a class="iref" href="#RFC1864"><b>9.1</b></a></li>
<li class="indline1"><em>RFC1945</em>&nbsp;&nbsp;<a class="iref" href="#RFC1945"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.RFC1945.1">B</a></li>
<li class="indline1"><em>RFC1950</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC1950.1">2.2</a>, <a class="iref" href="#RFC1950"><b>9.1</b></a></li>
<li class="indline1"><em>RFC1951</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC1951.1">2.2</a>, <a class="iref" href="#RFC1951"><b>9.1</b></a></li>
<li class="indline1"><em>RFC1952</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC1952.1">2.2</a>, <a class="iref" href="#RFC1952"><b>9.1</b></a></li>
<li class="indline1"><em>RFC2045</em>&nbsp;&nbsp;<a class="iref" href="#RFC2045"><b>9.1</b></a>, <a class="iref" href="#rfc.xref.RFC2045.1">A</a>, <a class="iref" href="#rfc.xref.RFC2045.2">A.1</a>, <a class="iref" href="#rfc.xref.RFC2045.3">A.2</a></li>
<li class="indline1"><em>RFC2046</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2046.1">2.3</a>, <a class="iref" href="#rfc.xref.RFC2046.2">2.3.2</a>, <a class="iref" href="#RFC2046"><b>9.1</b></a>, <a class="iref" href="#rfc.xref.RFC2046.3">A.2</a><ul class="ind">
<li class="indline1"><em>Section 5.1.1</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2046.2">2.3.2</a></li>
<li class="indline1"><em>RFC2049</em>&nbsp;&nbsp;<a class="iref" href="#RFC2049"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.RFC2049.1">A.2</a><ul class="ind">
<li class="indline1"><em>RFC2068</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2068.1">9.1</a>, <a class="iref" href="#rfc.xref.RFC2068.2">9.1</a>, <a class="iref" href="#rfc.xref.RFC2068.3">9.1</a>, <a class="iref" href="#RFC2068"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.RFC2068.4">B</a>, <a class="iref" href="#rfc.xref.RFC2068.5">C.1</a><ul class="ind">
<li class="indline1"><em>Section 19.6.2</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2068.5">C.1</a></li>
<li class="indline1"><em>RFC2076</em>&nbsp;&nbsp;<a class="iref" href="#RFC2076"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.RFC2076.1">B</a></li>
<li class="indline1"><em>RFC2183</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2183.1">7.2</a>, <a class="iref" href="#rfc.xref.RFC2183.2">7.2</a>, <a class="iref" href="#RFC2183"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.RFC2183.3">B.1</a><ul class="ind">
<li class="indline1"><em>Section 5</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2183.2">7.2</a></li>
<li class="indline1"><em>RFC2277</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2277.1">2.1</a>, <a class="iref" href="#RFC2277"><b>9.2</b></a></li>
<li class="indline1"><em>RFC2388</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2388.1">2.3.2</a>, <a class="iref" href="#RFC2388"><b>9.2</b></a></li>
<li class="indline1"><em>RFC2557</em>&nbsp;&nbsp;<a class="iref" href="#RFC2557"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.RFC2557.1">A.7</a>, <a class="iref" href="#rfc.xref.RFC2557.2">C.1</a></li>
<li class="indline1"><em>RFC2616</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC2616.1">1</a>, <a class="iref" href="#RFC2616"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.RFC2616.2">E.1</a></li>
<li class="indline1"><em>RFC3629</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC3629.1">2.1</a>, <a class="iref" href="#RFC3629"><b>9.2</b></a></li>
<li class="indline1"><em>RFC3864</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC3864.1">6.1</a>, <a class="iref" href="#RFC3864"><b>9.2</b></a></li>
<li class="indline1"><em>RFC4288</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC4288.1">2.3</a>, <a class="iref" href="#RFC4288"><b>9.2</b></a></li>
<li class="indline1"><em>RFC4647</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC4647.1">5.4</a>, <a class="iref" href="#rfc.xref.RFC4647.2">5.4</a>, <a class="iref" href="#RFC4647"><b>9.1</b></a><ul class="ind">
<li class="indline1"><em>Section 2.1</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC4647.1">5.4</a></li>
<li class="indline1"><em>Section 3.3.1</em>&nbsp;&nbsp;<a class="iref" href="#rfc.xref.RFC4647.2">5.4</a></li>
<li class="indline1"><em>RFC5322</em>&nbsp;&nbsp;<a class="iref" href="#RFC5322"><b>9.2</b></a>, <a class="iref" href="#rfc.xref.RFC5322.1">A</a></li>
<li class="indline1">URI header&nbsp;&nbsp;<a class="iref" href="#rfc.iref.u.1"><b>C.1</b></a></li>