source: draft-ietf-httpbis/latest/p5-range.xml @ 1446

Last change on this file since 1446 was 1443, checked in by julian.reschke@…, 8 years ago

bump up document dates; update to latest version of rfc2629.xslt.

  • Property svn:eol-style set to native
File size: 67.4 KB
Line 
1<?xml version="1.0" encoding="utf-8"?>
2<?xml-stylesheet type='text/xsl' href='../myxml2rfc.xslt'?>
3<!DOCTYPE rfc [
4  <!ENTITY MAY "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>MAY</bcp14>">
5  <!ENTITY MUST "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>MUST</bcp14>">
6  <!ENTITY MUST-NOT "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>MUST NOT</bcp14>">
7  <!ENTITY OPTIONAL "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>OPTIONAL</bcp14>">
8  <!ENTITY RECOMMENDED "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>RECOMMENDED</bcp14>">
9  <!ENTITY REQUIRED "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>REQUIRED</bcp14>">
10  <!ENTITY SHALL "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>SHALL</bcp14>">
11  <!ENTITY SHALL-NOT "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>SHALL NOT</bcp14>">
12  <!ENTITY SHOULD "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>SHOULD</bcp14>">
13  <!ENTITY SHOULD-NOT "<bcp14 xmlns='http://purl.org/net/xml2rfc/ext'>SHOULD NOT</bcp14>">
14  <!ENTITY ID-VERSION "latest">
15  <!ENTITY ID-MONTH "October">
16  <!ENTITY ID-YEAR "2011">
17  <!ENTITY notation                   "<xref target='Part1' x:rel='#notation' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
18  <!ENTITY notation-abnf              "<xref target='Part1' x:rel='#notation.abnf' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
19  <!ENTITY acks                       "<xref target='Part1' x:rel='#acks' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
20  <!ENTITY basic-rules                "<xref target='Part1' x:rel='#basic.rules' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
21  <!ENTITY field-rules                "<xref target='Part1' x:rel='#field.rules' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
22  <!ENTITY http-date                  "<xref target='Part2' x:rel='#http.date' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
23  <!ENTITY messaging                  "<xref target='Part1' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
24  <!ENTITY entity-tags                "<xref target='Part4' x:rel='#header.etag' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
25  <!ENTITY weak-and-strong-validators "<xref target='Part4' x:rel='#weak.and.strong.validators' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
26  <!ENTITY lastmod-comparison         "<xref target='Part4' x:rel='#lastmod.comparison' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
27]>
28<?rfc toc="yes" ?>
29<?rfc symrefs="yes" ?>
30<?rfc sortrefs="yes" ?>
31<?rfc compact="yes"?>
32<?rfc subcompact="no" ?>
33<?rfc linkmailto="no" ?>
34<?rfc editing="no" ?>
35<?rfc comments="yes"?>
36<?rfc inline="yes"?>
37<?rfc rfcedstyle="yes"?>
38<?rfc-ext allow-markup-in-artwork="yes" ?>
39<?rfc-ext include-references-in-index="yes" ?>
40<rfc obsoletes="2616" category="std" x:maturity-level="draft"
41     ipr="pre5378Trust200902" docName="draft-ietf-httpbis-p5-range-&ID-VERSION;"     xmlns:x='http://purl.org/net/xml2rfc/ext'>
42<front>
43
44  <title abbrev="HTTP/1.1, Part 5">HTTP/1.1, part 5: Range Requests and Partial Responses</title>
45
46  <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
47    <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
48    <address>
49      <postal>
50        <street>345 Park Ave</street>
51        <city>San Jose</city>
52        <region>CA</region>
53        <code>95110</code>
54        <country>USA</country>
55      </postal>
56      <email>fielding@gbiv.com</email>
57      <uri>http://roy.gbiv.com/</uri>
58    </address>
59  </author>
60
61  <author initials="J." surname="Gettys" fullname="Jim Gettys">
62    <organization abbrev="Alcatel-Lucent">Alcatel-Lucent Bell Labs</organization>
63    <address>
64      <postal>
65        <street>21 Oak Knoll Road</street>
66        <city>Carlisle</city>
67        <region>MA</region>
68        <code>01741</code>
69        <country>USA</country>
70      </postal>
71      <email>jg@freedesktop.org</email>
72      <uri>http://gettys.wordpress.com/</uri>
73    </address>
74  </author>
75 
76  <author initials="J." surname="Mogul" fullname="Jeffrey C. Mogul">
77    <organization abbrev="HP">Hewlett-Packard Company</organization>
78    <address>
79      <postal>
80        <street>HP Labs, Large Scale Systems Group</street>
81        <street>1501 Page Mill Road, MS 1177</street>
82        <city>Palo Alto</city>
83        <region>CA</region>
84        <code>94304</code>
85        <country>USA</country>
86      </postal>
87      <email>JeffMogul@acm.org</email>
88    </address>
89  </author>
90
91  <author initials="H." surname="Frystyk" fullname="Henrik Frystyk Nielsen">
92    <organization abbrev="Microsoft">Microsoft Corporation</organization>
93    <address>
94      <postal>
95        <street>1 Microsoft Way</street>
96        <city>Redmond</city>
97        <region>WA</region>
98        <code>98052</code>
99        <country>USA</country>
100      </postal>
101      <email>henrikn@microsoft.com</email>
102    </address>
103  </author>
104
105  <author initials="L." surname="Masinter" fullname="Larry Masinter">
106    <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
107    <address>
108      <postal>
109        <street>345 Park Ave</street>
110        <city>San Jose</city>
111        <region>CA</region>
112        <code>95110</code>
113        <country>USA</country>
114      </postal>
115      <email>LMM@acm.org</email>
116      <uri>http://larry.masinter.net/</uri>
117    </address>
118  </author>
119 
120  <author initials="P." surname="Leach" fullname="Paul J. Leach">
121    <organization abbrev="Microsoft">Microsoft Corporation</organization>
122    <address>
123      <postal>
124        <street>1 Microsoft Way</street>
125        <city>Redmond</city>
126        <region>WA</region>
127        <code>98052</code>
128      </postal>
129      <email>paulle@microsoft.com</email>
130    </address>
131  </author>
132   
133  <author initials="T." surname="Berners-Lee" fullname="Tim Berners-Lee">
134    <organization abbrev="W3C/MIT">World Wide Web Consortium</organization>
135    <address>
136      <postal>
137        <street>MIT Computer Science and Artificial Intelligence Laboratory</street>
138        <street>The Stata Center, Building 32</street>
139        <street>32 Vassar Street</street>
140        <city>Cambridge</city>
141        <region>MA</region>
142        <code>02139</code>
143        <country>USA</country>
144      </postal>
145      <email>timbl@w3.org</email>
146      <uri>http://www.w3.org/People/Berners-Lee/</uri>
147    </address>
148  </author>
149
150  <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
151    <organization abbrev="W3C">World Wide Web Consortium</organization>
152    <address>
153      <postal>
154        <street>W3C / ERCIM</street>
155        <street>2004, rte des Lucioles</street>
156        <city>Sophia-Antipolis</city>
157        <region>AM</region>
158        <code>06902</code>
159        <country>France</country>
160      </postal>
161      <email>ylafon@w3.org</email>
162      <uri>http://www.raubacapeu.net/people/yves/</uri>
163    </address>
164  </author>
165
166  <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
167    <organization abbrev="greenbytes">greenbytes GmbH</organization>
168    <address>
169      <postal>
170        <street>Hafenweg 16</street>
171        <city>Muenster</city><region>NW</region><code>48155</code>
172        <country>Germany</country>
173      </postal>
174      <phone>+49 251 2807760</phone>
175      <facsimile>+49 251 2807761</facsimile>
176      <email>julian.reschke@greenbytes.de</email>
177      <uri>http://greenbytes.de/tech/webdav/</uri>
178    </address>
179  </author>
180
181  <date month="&ID-MONTH;" year="&ID-YEAR;"/>
182  <workgroup>HTTPbis Working Group</workgroup>
183
184<abstract>
185<t>
186   The Hypertext Transfer Protocol (HTTP) is an application-level protocol for
187   distributed, collaborative, hypertext information systems. HTTP has been in
188   use by the World Wide Web global information initiative since 1990. This
189   document is Part 5 of the seven-part specification that defines the protocol
190   referred to as "HTTP/1.1" and, taken together, obsoletes RFC 2616.
191</t>
192<t>
193   Part 5 defines range-specific requests and the rules for constructing and
194   combining responses to those requests.
195</t>
196</abstract>
197
198<note title="Editorial Note (To be removed by RFC Editor)">
199  <t>
200    Discussion of this draft should take place on the HTTPBIS working group
201    mailing list (ietf-http-wg@w3.org), which is archived at
202    <eref target="http://lists.w3.org/Archives/Public/ietf-http-wg/"/>.
203  </t>
204  <t>
205    The current issues list is at
206    <eref target="http://tools.ietf.org/wg/httpbis/trac/report/3"/> and related
207    documents (including fancy diffs) can be found at
208    <eref target="http://tools.ietf.org/wg/httpbis/"/>.
209  </t>
210  <t>
211    The changes in this draft are summarized in <xref target="changes.since.16"/>.
212  </t>
213</note>
214</front>
215<middle>
216<section title="Introduction" anchor="introduction">
217<t>
218   HTTP clients often encounter interrupted data transfers as a result
219   of cancelled requests or dropped connections.  When a client has stored
220   a partial representation, it is desirable to request the remainder
221   of that representation in a subsequent request rather than transfer
222   the entire representation.
223   There are also a number of Web applications that benefit from being
224   able to request only a subset of a larger representation, such as a
225   single page of a very large document or only part of an image to be
226   rendered by a device with limited local storage.
227</t>
228<t>
229   This document defines HTTP/1.1 range requests,
230   partial responses, and the multipart/byteranges media type.
231   The protocol for range requests is an &OPTIONAL; feature of HTTP,
232   designed so resources or recipients that do not implement this feature
233   can respond as if it is a normal GET request without impacting
234   interoperability.  Partial responses are indicated by a distinct status
235   code to not be mistaken for full responses by intermediate caches
236   that might not implement the feature.
237</t>
238<t>
239   Although the HTTP range request mechanism is designed to allow for
240   extensible range types, this specification only defines requests for
241   byte ranges.
242</t>
243
244<section title="Requirements" anchor="intro.requirements">
245<t>
246   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
247   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
248   document are to be interpreted as described in <xref target="RFC2119"/>.
249</t>
250<t>
251   An implementation is not compliant if it fails to satisfy one or more
252   of the "MUST" or "REQUIRED" level requirements for the protocols it
253   implements. An implementation that satisfies all the "MUST" or "REQUIRED"
254   level and all the "SHOULD" level requirements for its protocols is said
255   to be "unconditionally compliant"; one that satisfies all the "MUST"
256   level requirements but not all the "SHOULD" level requirements for its
257   protocols is said to be "conditionally compliant".
258</t>
259</section>
260
261<section title="Syntax Notation" anchor="notation">
262  <x:anchor-alias value="ALPHA"/>
263  <x:anchor-alias value="CHAR"/>
264  <x:anchor-alias value="CR"/>
265  <x:anchor-alias value="DIGIT"/>
266  <x:anchor-alias value="LF"/>
267  <x:anchor-alias value="OCTET"/>
268  <x:anchor-alias value="SP"/>
269  <x:anchor-alias value="VCHAR"/>
270<t>
271  This specification uses the ABNF syntax defined in &notation; (which
272  extends the syntax defined in <xref target="RFC5234"/> with a list rule).
273  <xref target="collected.abnf"/> shows the collected ABNF, with the list
274  rule expanded.
275</t>
276<t>
277  The following core rules are included by
278  reference, as defined in <xref target="RFC5234" x:fmt="," x:sec="B.1"/>:
279  ALPHA (letters), CR (carriage return), CRLF (CR LF), CTL (controls),
280  DIGIT (decimal 0-9), DQUOTE (double quote),
281  HEXDIG (hexadecimal 0-9/A-F/a-f), LF (line feed),
282  OCTET (any 8-bit sequence of data), SP (space), and
283  VCHAR (any visible US-ASCII character).
284</t>
285
286<section title="Core Rules" anchor="core.rules">
287  <x:anchor-alias value="token"/>
288  <x:anchor-alias value="OWS"/>
289  <x:anchor-alias value="HTTP-date"/>
290<t>
291  The core rules below are defined in <xref target="Part1"/> and
292  <xref target="Part2"/>:
293</t>
294<figure><artwork type="abnf2616">
295  <x:ref>OWS</x:ref>        = &lt;OWS, defined in &basic-rules;&gt;
296  <x:ref>token</x:ref>      = &lt;token, defined in &field-rules;&gt;
297  <x:ref>HTTP-date</x:ref>  = &lt;HTTP-date, defined in &http-date;&gt;
298</artwork></figure>
299</section>
300
301<section title="ABNF Rules defined in other Parts of the Specification" anchor="abnf.dependencies">
302  <x:anchor-alias value="entity-tag"/>
303<t>
304  The ABNF rules below are defined in other parts:
305</t>
306<figure><!--Part4--><artwork type="abnf2616">
307  <x:ref>entity-tag</x:ref> = &lt;entity-tag, defined in &entity-tags;&gt;
308</artwork></figure>
309</section>
310
311</section>
312
313</section>
314
315
316<section title="Range Units" anchor="range.units">
317  <x:anchor-alias value="bytes-unit"/>
318  <x:anchor-alias value="other-range-unit"/>
319  <x:anchor-alias value="range-unit"/>
320<t>
321   HTTP/1.1 allows a client to request that only part (a range) of the
322   representation be included within the response. HTTP/1.1 uses range
323   units in the Range (<xref target="header.range"/>) and Content-Range (<xref target="header.content-range"/>)
324   header fields. A representation can be broken down into subranges according
325   to various structural units.
326</t>
327<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="range-unit"/><iref primary="true" item="Grammar" subitem="bytes-unit"/><iref primary="true" item="Grammar" subitem="other-range-unit"/>
328  <x:ref>range-unit</x:ref>       = <x:ref>bytes-unit</x:ref> / <x:ref>other-range-unit</x:ref>
329  <x:ref>bytes-unit</x:ref>       = "bytes"
330  <x:ref>other-range-unit</x:ref> = <x:ref>token</x:ref>
331</artwork></figure>
332<t>
333  HTTP/1.1 has been designed to allow implementations of applications
334  that do not depend on knowledge of ranges. The only range unit defined
335  by HTTP/1.1 is "bytes". Additional specifiers can be defined as described
336  in <xref target="range.specifier.registry"/>.
337</t>
338<t>
339  If a range unit is not understood in a request, a server &MUST; ignore
340  the whole Range header field (<xref target="header.range"/>).
341  If a range unit is not understood in a response, an intermediary
342  &SHOULD; pass the response to the client; a client &MUST; fail.
343</t>
344
345<section title="Range Specifier Registry" anchor="range.specifier.registry">
346<t>
347   The HTTP Range Specifier Registry defines the name space for the range
348   specifier names.
349</t>
350<t>
351   Registrations &MUST; include the following fields:
352   <list style="symbols">
353     <t>Name</t>
354     <t>Description</t>
355     <t>Pointer to specification text</t>
356   </list>
357</t>
358<t>
359  Values to be added to this name space are subject to IETF review
360  (<xref target="RFC5226" x:fmt="," x:sec="4.1"/>).
361</t>
362<t>
363   The registry itself is maintained at
364   <eref target="http://www.iana.org/assignments/http-range-specifiers"/>.
365</t>
366</section>
367
368</section>
369
370<section title="Status Code Definitions" anchor="status.code.definitions">
371<section title="206 Partial Content" anchor="status.206">
372  <iref primary="true" item="206 Partial Content (status code)" x:for-anchor=""/>
373  <iref primary="true" item="Status Codes" subitem="206 Partial Content" x:for-anchor=""/>
374<t>
375   The server has fulfilled the partial GET request for the resource.
376   The request &MUST; have included a Range header field (<xref target="header.range"/>)
377   indicating the desired range, and &MAY; have included an If-Range
378   header field (<xref target="header.if-range"/>) to make the request conditional.
379</t>
380<t>
381   The response &MUST; include the following header fields:
382  <list style="symbols">
383    <t>
384        Either a Content-Range header field (<xref target="header.content-range"/>) indicating
385        the range included with this response, or a multipart/byteranges
386        Content-Type including Content-Range fields for each part. If a
387        Content-Length header field is present in the response, its
388        value &MUST; match the actual number of octets transmitted in the
389        message-body.
390    </t>
391    <t>
392        Date
393    </t>
394    <t>
395        Cache-Control, ETag, Expires, Content-Location, Last-Modified,
396        and/or Vary, if the header field would have been sent in a 200
397        response to the same request
398    </t>
399  </list>
400</t>
401<t>
402   If the 206 response is the result of an If-Range request, the response
403   &SHOULD-NOT; include other representation header fields. Otherwise, the response
404   &MUST; include all of the representation header fields that would have been returned
405   with a 200 (OK) response to the same request.
406</t>
407</section>
408
409<section title="416 Requested Range Not Satisfiable" anchor="status.416">
410  <iref primary="true" item="416 Requested Range Not Satisfiable (status code)" x:for-anchor=""/>
411  <iref primary="true" item="Status Codes" subitem="416 Requested Range Not Satisfiable" x:for-anchor=""/>
412<t>
413   A server &SHOULD; return a response with this status code if a request
414   included a Range header field (<xref target="header.range"/>), and none of
415   the ranges-specifier values in this field overlap the current extent
416   of the selected resource, and the request did not include an If-Range
417   header field (<xref target="header.if-range"/>). (For byte-ranges,
418   this means that the first-byte-pos of all of the byte-range-spec values were
419   greater than the current length of the selected resource.)
420</t>
421<t>
422   When this status code is returned for a byte-range request, the
423   response &SHOULD; include a Content-Range header field
424   specifying the current length of the representation (see <xref target="header.content-range"/>).
425   This response &MUST-NOT; use the multipart/byteranges content-type.
426</t>
427</section>
428</section>
429
430<section title="Combining Ranges" anchor="combining.byte.ranges">
431<t>
432   A response might transfer only a subrange of a representation if the
433   connection closed prematurely or if the request used one or more Range
434   specifications.  After several such transfers, a client might have
435   received several ranges of the same representation.  These ranges can only
436   be safely combined if they all have in common the same strong validator,
437   where "strong validator" is defined to be either an entity-tag that is
438   not marked as weak (&entity-tags;) or, if no entity-tag is provided, a
439   Last-Modified value that is strong in the sense defined by
440   &lastmod-comparison;.
441</t>
442<t>
443   When a client receives an incomplete 200 (OK) or 206 (Partial Content)
444   response and already has one or more stored responses for the same method
445   and effective request URI, all of the stored responses with the same
446   strong validator &MAY; be combined with the partial content in this new
447   response.  If none of the stored responses contain the same strong
448   validator, then this new response corresponds to a new representation
449   and &MUST-NOT; be combined with the existing stored responses.
450</t>
451<t>
452   If the new response is an incomplete 200 (OK) response, then the header
453   fields of that new response are used for any combined response and replace
454   those of the matching stored responses.
455</t>
456<t>
457   If the new response is a 206 (Partial Content) response and at least one
458   of the matching stored responses is a 200 (OK), then the combined response
459   header fields consist of the most recent 200 response's header fields.
460   If all of the matching stored responses are 206 responses, then the
461   stored response with the most header fields is used as the source of
462   header fields for the combined response, except that the client &MUST;
463   use other header fields provided in the new response, aside from
464   Content-Range, to replace all instances of the corresponding header
465   fields in the stored response.
466</t>
467<t>
468   The combined response message-body consists of the union of partial
469   content ranges in the new response and each of the selected responses.
470   If the union consists of the entire range of the representation, then the
471   combined response &MUST; be recorded as a complete 200 (OK) response
472   with a Content-Length header field that reflects the complete length.
473   Otherwise, the combined response(s) &MUST; include a Content-Range
474   header field describing the included range(s) and be recorded as
475   incomplete.  If the union consists of a discontinuous range of the
476   representation, then the client &MAY; store it as either a multipart range
477   response or as multiple 206 responses with one continuous range each.
478</t>
479</section>
480
481<section title="Header Field Definitions" anchor="header.field.definitions">
482<t>
483   This section defines the syntax and semantics of HTTP/1.1 header fields
484   related to range requests and partial responses.
485</t>
486
487<section title="Accept-Ranges" anchor="header.accept-ranges">
488  <iref primary="true" item="Accept-Ranges header field" x:for-anchor=""/>
489  <iref primary="true" item="Header Fields" subitem="Accept-Ranges" x:for-anchor=""/>
490  <x:anchor-alias value="Accept-Ranges"/>
491  <x:anchor-alias value="acceptable-ranges"/>
492<t>
493   The "Accept-Ranges" header field allows a resource to indicate
494   its acceptance of range requests.
495</t>
496<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="Accept-Ranges"/><iref primary="true" item="Grammar" subitem="acceptable-ranges"/>
497  <x:ref>Accept-Ranges</x:ref>     = <x:ref>acceptable-ranges</x:ref>
498  <x:ref>acceptable-ranges</x:ref> = 1#<x:ref>range-unit</x:ref> / "none"
499</artwork></figure>
500<t>
501      Origin servers that accept byte-range requests &MAY; send
502</t>
503<figure><artwork type="example">
504  Accept-Ranges: bytes
505</artwork></figure>
506<t>
507      but are not required to do so. Clients &MAY; generate range
508      requests without having received this header field for the resource
509      involved. Range units are defined in <xref target="range.units"/>.
510</t>
511<t>
512      Servers that do not accept any kind of range request for a
513      resource &MAY; send
514</t>
515<figure><artwork type="example">
516  Accept-Ranges: none
517</artwork></figure>
518<t>
519      to advise the client not to attempt a range request.
520</t>
521</section>
522
523<section title="Content-Range" anchor="header.content-range">
524  <iref primary="true" item="Content-Range header field" x:for-anchor=""/>
525  <iref primary="true" item="Header Fields" subitem="Content-Range" x:for-anchor=""/>
526  <x:anchor-alias value="byte-content-range-spec"/>
527  <x:anchor-alias value="byte-range-resp-spec"/>
528  <x:anchor-alias value="Content-Range"/>
529  <x:anchor-alias value="instance-length"/>
530  <x:anchor-alias value="other-content-range-spec"/>
531  <x:anchor-alias value="other-range-resp-spec"/>
532<t>
533   The "Content-Range" header field is sent with a partial representation to
534   specify where in the full representation the payload body is intended to be
535   applied.
536</t>
537<t>   
538   Range units are defined in <xref target="range.units"/>.
539</t>
540<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="Content-Range"/><iref primary="true" item="Grammar" subitem="byte-content-range-spec"/><iref primary="true" item="Grammar" subitem="byte-range-resp-spec"/><iref primary="true" item="Grammar" subitem="instance-length"/>
541  <x:ref>Content-Range</x:ref>           = <x:ref>byte-content-range-spec</x:ref>
542                          / <x:ref>other-content-range-spec</x:ref>
543                         
544  <x:ref>byte-content-range-spec</x:ref> = <x:ref>bytes-unit</x:ref> <x:ref>SP</x:ref>
545                            <x:ref>byte-range-resp-spec</x:ref> "/"
546                            ( <x:ref>instance-length</x:ref> / "*" )
547 
548  <x:ref>byte-range-resp-spec</x:ref>    = (<x:ref>first-byte-pos</x:ref> "-" <x:ref>last-byte-pos</x:ref>)
549                          / "*"
550                         
551  <x:ref>instance-length</x:ref>         = 1*<x:ref>DIGIT</x:ref>
552 
553  <x:ref>other-content-range-spec</x:ref> = <x:ref>other-range-unit</x:ref> <x:ref>SP</x:ref>
554                             <x:ref>other-range-resp-spec</x:ref>
555  <x:ref>other-range-resp-spec</x:ref>    = *<x:ref>CHAR</x:ref>
556</artwork></figure>
557<t>
558   The header field &SHOULD; indicate the total length of the full representation,
559   unless this length is unknown or difficult to determine. The asterisk
560   "*" character means that the instance-length is unknown at the time
561   when the response was generated.
562</t>
563<t>
564   Unlike byte-ranges-specifier values (see <xref target="byte.ranges"/>), a byte-range-resp-spec
565   &MUST; only specify one range, and &MUST; contain
566   absolute byte positions for both the first and last byte of the
567   range.
568</t>
569<t>
570   A byte-content-range-spec with a byte-range-resp-spec whose last-byte-pos
571   value is less than its first-byte-pos value, or whose
572   instance-length value is less than or equal to its last-byte-pos
573   value, is invalid. The recipient of an invalid byte-content-range-spec
574   &MUST; ignore it and any content transferred along with it.
575</t>
576<t>
577   In the case of a byte range request:
578   A server sending a response with status code 416 (Requested range not
579   satisfiable) &SHOULD; include a Content-Range field with a byte-range-resp-spec
580   of "*". The instance-length specifies the current length of
581   the selected resource. A response with status code 206 (Partial
582   Content) &MUST-NOT; include a Content-Range field with a byte-range-resp-spec of "*".
583</t>
584<t>
585   Examples of byte-content-range-spec values, assuming that the representation
586   contains a total of 1234 bytes:
587   <list style="symbols">
588      <t>
589        The first 500 bytes:
590<figure><artwork type="example" x:indent-with="   ">
591  bytes 0-499/1234
592</artwork></figure>
593      </t>   
594      <t>
595        The second 500 bytes:
596<figure><artwork type="example" x:indent-with="   ">
597  bytes 500-999/1234
598</artwork></figure>
599      </t>   
600      <t>
601        All except for the first 500 bytes:
602<figure><artwork type="example" x:indent-with="   ">
603  bytes 500-1233/1234
604</artwork></figure>
605      </t>   
606      <t>
607        The last 500 bytes:
608<figure><artwork type="example" x:indent-with="   ">
609  bytes 734-1233/1234
610</artwork></figure>
611      </t>   
612   </list>
613</t>
614<t>
615   When an HTTP message includes the content of a single range (for
616   example, a response to a request for a single range, or to a request
617   for a set of ranges that overlap without any holes), this content is
618   transmitted with a Content-Range header field, and a Content-Length header
619   field showing the number of bytes actually transferred. For example,
620</t>
621<figure><artwork type="example">
622  HTTP/1.1 206 Partial Content
623  Date: Wed, 15 Nov 1995 06:25:24 GMT
624  Last-Modified: Wed, 15 Nov 1995 04:58:08 GMT
625  Content-Range: bytes 21010-47021/47022
626  Content-Length: 26012
627  Content-Type: image/gif
628</artwork></figure>
629<t>
630   When an HTTP message includes the content of multiple ranges (for
631   example, a response to a request for multiple non-overlapping
632   ranges), these are transmitted as a multipart message. The multipart
633   media type used for this purpose is "multipart/byteranges" as defined
634   in <xref target="internet.media.type.multipart.byteranges"/>.
635</t>
636<t>
637   A response to a request for a single range &MUST-NOT; be sent using the
638   multipart/byteranges media type.  A response to a request for
639   multiple ranges, whose result is a single range, &MAY; be sent as a
640   multipart/byteranges media type with one part. A client that cannot
641   decode a multipart/byteranges message &MUST-NOT; ask for multiple
642   ranges in a single request.
643</t>
644<t>
645   When a client requests multiple ranges in one request, the
646   server &SHOULD; return them in the order that they appeared in the
647   request.
648</t>
649<t>
650   If the server ignores a byte-range-spec because it is syntactically
651   invalid, the server &SHOULD; treat the request as if the invalid Range
652   header field did not exist. (Normally, this means return a 200
653   response containing the full representation).
654</t>
655<t>
656   If the server receives a request (other than one including an If-Range
657   header field) with an unsatisfiable Range header
658   field (that is, all of whose byte-range-spec values have a
659   first-byte-pos value greater than the current length of the selected
660   resource), it &SHOULD; return a response code of 416 (Requested range
661   not satisfiable) (<xref target="status.416"/>).
662</t>
663<x:note>
664  <t>
665    <x:h>Note:</x:h> Clients cannot depend on servers to send a 416 (Requested
666    range not satisfiable) response instead of a 200 (OK) response for
667    an unsatisfiable Range header field, since not all servers
668    implement this header field.
669  </t>
670</x:note>
671</section>
672
673<section title="If-Range" anchor="header.if-range">
674  <iref primary="true" item="If-Range header field" x:for-anchor=""/>
675  <iref primary="true" item="Header Fields" subitem="If-Range" x:for-anchor=""/>
676  <x:anchor-alias value="If-Range"/>
677<t>
678   If a client has a partial copy of a representation and wishes
679   to have an up-to-date copy of the entire representation, it
680   could use the Range header field with a conditional GET (using
681   either or both of If-Unmodified-Since and If-Match.) However, if the
682   condition fails because the representation has been modified, the client
683   would then have to make a second request to obtain the entire current
684   representation.
685</t>
686<t>
687   The "If-Range" header field allows a client to "short-circuit" the second
688   request. Informally, its meaning is "if the representation is unchanged, send
689   me the part(s) that I am missing; otherwise, send me the entire new
690   representation".
691</t>
692<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="If-Range"/>
693  <x:ref>If-Range</x:ref> = <x:ref>entity-tag</x:ref> / <x:ref>HTTP-date</x:ref>
694</artwork></figure>
695<t>
696   Clients &MUST-NOT; use an entity-tag marked as weak in an If-Range
697   field value and &MUST-NOT; use a Last-Modified date in an If-Range
698   field value unless it has no entity-tag for the representation and
699   the Last-Modified date it does have for the representation is strong
700   in the sense defined by &lastmod-comparison;.
701</t>
702<t>
703   A server that evaluates a conditional range request that is applicable
704   to one of its representations &MUST; evaluate the condition as false if
705   the entity-tag used as a validator is marked as weak or, when an HTTP-date
706   is used as the validator, if the date value is not strong in the sense
707   defined by &lastmod-comparison;. (A server can distinguish between a
708   valid HTTP-date and any form of entity-tag by examining the first
709   two characters.)
710</t>
711<t>
712   The If-Range header field &SHOULD; only be sent by clients together with
713   a Range header field.  The If-Range header field &MUST; be ignored if it
714   is received in a request that does not include a Range header field.
715   The If-Range header field &MUST; be ignored by a server that does not
716   support the sub-range operation.
717</t>
718<t>
719   If the validator given in the If-Range header field matches the current
720   validator for the selected representation of the target resource, then
721   the server &SHOULD; send the specified sub-range of the representation
722   using a 206 (Partial Content) response. If the validator does not match,
723   then the server &SHOULD; send the entire representation using a 200 (OK)
724   response.
725</t>
726</section>
727
728<section title="Range" anchor="header.range">
729  <iref primary="true" item="Range header field" x:for-anchor=""/>
730  <iref primary="true" item="Header Fields" subitem="Range" x:for-anchor=""/>
731
732<section title="Byte Ranges" anchor="byte.ranges">
733<t>
734   Since all HTTP representations are transferred as sequences
735   of bytes, the concept of a byte range is meaningful for any HTTP
736   representation. (However, not all clients and servers need to support byte-range
737   operations.)
738</t>
739<t>
740   Byte range specifications in HTTP apply to the sequence of bytes in
741   the representation body (not necessarily the same as the message-body).
742</t>
743<t anchor="rule.ranges-specifier">
744  <x:anchor-alias value="byte-range-set"/>
745  <x:anchor-alias value="byte-range-spec"/>
746  <x:anchor-alias value="byte-ranges-specifier"/>
747  <x:anchor-alias value="first-byte-pos"/>
748  <x:anchor-alias value="last-byte-pos"/>
749  <x:anchor-alias value="ranges-specifier"/>
750  <x:anchor-alias value="suffix-byte-range-spec"/>
751  <x:anchor-alias value="suffix-length"/>
752
753   A byte range operation &MAY; specify a single range of bytes, or a set
754   of ranges within a single representation.
755</t>
756<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="ranges-specifier"/><iref primary="true" item="Grammar" subitem="byte-ranges-specifier"/><iref primary="true" item="Grammar" subitem="byte-range-set"/><iref primary="true" item="Grammar" subitem="byte-range-spec"/><iref primary="true" item="Grammar" subitem="first-byte-pos"/><iref primary="true" item="Grammar" subitem="last-byte-pos"/>
757  <x:ref>byte-ranges-specifier</x:ref> = <x:ref>bytes-unit</x:ref> "=" <x:ref>byte-range-set</x:ref>
758  <x:ref>byte-range-set</x:ref>  = 1#( <x:ref>byte-range-spec</x:ref> / <x:ref>suffix-byte-range-spec</x:ref> )
759  <x:ref>byte-range-spec</x:ref> = <x:ref>first-byte-pos</x:ref> "-" [ <x:ref>last-byte-pos</x:ref> ]
760  <x:ref>first-byte-pos</x:ref>  = 1*<x:ref>DIGIT</x:ref>
761  <x:ref>last-byte-pos</x:ref>   = 1*<x:ref>DIGIT</x:ref>
762</artwork></figure>
763<t>
764   The first-byte-pos value in a byte-range-spec gives the byte-offset
765   of the first byte in a range. The last-byte-pos value gives the
766   byte-offset of the last byte in the range; that is, the byte
767   positions specified are inclusive. Byte offsets start at zero.
768</t>
769<t>
770   If the last-byte-pos value is present, it &MUST; be greater than or
771   equal to the first-byte-pos in that byte-range-spec, or the byte-range-spec
772   is syntactically invalid. The recipient of a byte-range-set
773   that includes one or more syntactically invalid byte-range-spec
774   values &MUST; ignore the header field that includes that byte-range-set.
775</t>
776<t>
777   If the last-byte-pos value is absent, or if the value is greater than
778   or equal to the current length of the representation body, last-byte-pos is
779   taken to be equal to one less than the current length of the representation
780   in bytes.
781</t>
782<t>
783   By its choice of last-byte-pos, a client can limit the number of
784   bytes retrieved without knowing the size of the representation.
785</t>
786<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="suffix-byte-range-spec"/><iref primary="true" item="Grammar" subitem="suffix-length"/>
787  <x:ref>suffix-byte-range-spec</x:ref> = "-" <x:ref>suffix-length</x:ref>
788  <x:ref>suffix-length</x:ref> = 1*<x:ref>DIGIT</x:ref>
789</artwork></figure>
790<t>
791   A suffix-byte-range-spec is used to specify the suffix of the
792   representation body, of a length given by the suffix-length value. (That is,
793   this form specifies the last N bytes of a representation.) If the
794   representation is shorter than the specified suffix-length, the entire
795   representation is used.
796</t>
797<t>
798   If a syntactically valid byte-range-set includes at least one byte-range-spec
799   whose first-byte-pos is less than the current length of
800   the representation, or at least one suffix-byte-range-spec with a non-zero
801   suffix-length, then the byte-range-set is satisfiable.
802   Otherwise, the byte-range-set is unsatisfiable. If the byte-range-set
803   is unsatisfiable, the server &SHOULD; return a response with a
804   416 (Requested range not satisfiable) status code. Otherwise, the server
805   &SHOULD; return a response with a 206 (Partial Content) status code
806   containing the satisfiable ranges of the representation.
807</t>
808<t>
809   Examples of byte-ranges-specifier values (assuming a representation of
810   length 10000):
811  <list style="symbols">
812     <t>The first 500 bytes (byte offsets 0-499, inclusive):
813<figure><artwork type="example" x:indent-with="   ">
814  bytes=0-499
815</artwork></figure>
816    </t>
817     <t>The second 500 bytes (byte offsets 500-999, inclusive):
818<figure><artwork type="example" x:indent-with="   ">
819  bytes=500-999
820</artwork></figure>
821    </t>
822     <t>The final 500 bytes (byte offsets 9500-9999, inclusive):
823<figure><artwork type="example" x:indent-with="   ">
824  bytes=-500
825</artwork></figure>
826    Or:
827<figure><artwork type="example" x:indent-with="   ">
828  bytes=9500-
829</artwork></figure>
830    </t>
831     <t>The first and last bytes only (bytes 0 and 9999):
832<figure><artwork type="example" x:indent-with="   ">
833  bytes=0-0,-1
834</artwork></figure>
835     </t>
836     <t>Several legal but not canonical specifications of the second 500
837        bytes (byte offsets 500-999, inclusive):
838<figure><artwork type="example" x:indent-with="   ">
839  bytes=500-600,601-999
840  bytes=500-700,601-999
841</artwork></figure>
842     </t>
843  </list>
844</t>
845</section>
846
847<section title="Range Retrieval Requests" anchor="range.retrieval.requests">
848  <x:anchor-alias value="Range"/>
849  <x:anchor-alias value="other-ranges-specifier"/>
850  <x:anchor-alias value="other-range-set"/>
851<t>
852   The "Range" header field defines the GET method (conditional or
853   not) to request one or more sub-ranges of the response representation body, instead
854   of the entire representation body.
855</t>
856<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="Range"/>
857  <x:ref>Range</x:ref> = <x:ref>byte-ranges-specifier</x:ref> / <x:ref>other-ranges-specifier</x:ref>
858  <x:ref>other-ranges-specifier</x:ref> = <x:ref>other-range-unit</x:ref> "=" <x:ref>other-range-set</x:ref>
859  <x:ref>other-range-set</x:ref> = 1*<x:ref>CHAR</x:ref>
860</artwork></figure>
861<t>
862   A server &MAY; ignore the Range header field. However, origin
863   servers and intermediate caches ought to support byte ranges when
864   possible, since Range supports efficient recovery from partially
865   failed transfers, and supports efficient partial retrieval of large
866   representations.
867</t>
868<t>
869   If the server supports the Range header field and the specified range or
870   ranges are appropriate for the representation:
871  <list style="symbols">
872     <t>The presence of a Range header field in an unconditional GET modifies
873        what is returned if the GET is otherwise successful. In other
874        words, the response carries a status code of 206 (Partial
875        Content) instead of 200 (OK).</t>
876
877     <t>The presence of a Range header field in a conditional GET (a request
878        using one or both of If-Modified-Since and If-None-Match, or
879        one or both of If-Unmodified-Since and If-Match) modifies what
880        is returned if the GET is otherwise successful and the
881        condition is true. It does not affect the 304 (Not Modified)
882        response returned if the conditional is false.</t>
883  </list>
884</t>
885<t>
886   In some cases, it might be more appropriate to use the If-Range
887   header field (see <xref target="header.if-range"/>) in addition to the Range
888   header field.
889</t>
890<t>
891   If a proxy that supports ranges receives a Range request, forwards
892   the request to an inbound server, and receives an entire representation in
893   reply, it &MAY; only return the requested range to its client.
894</t>
895</section>
896</section>
897</section>
898
899<section title="IANA Considerations" anchor="IANA.considerations">
900
901<section title="Status Code Registration" anchor="status.code.registration">
902<t>
903   The HTTP Status Code Registry located at <eref target="http://www.iana.org/assignments/http-status-codes"/>
904   shall be updated with the registrations below:
905</t>
906<?BEGININC p5-range.iana-status-codes ?>
907<!--AUTOGENERATED FROM extract-status-code-defs.xslt, do not edit manually-->
908<texttable align="left" suppress-title="true" anchor="iana.status.code.registration.table">
909   <ttcol>Value</ttcol>
910   <ttcol>Description</ttcol>
911   <ttcol>Reference</ttcol>
912   <c>206</c>
913   <c>Partial Content</c>
914   <c>
915      <xref target="status.206"/>
916   </c>
917   <c>416</c>
918   <c>Requested Range Not Satisfiable</c>
919   <c>
920      <xref target="status.416"/>
921   </c>
922</texttable>
923<!--(END)-->
924<?ENDINC p5-range.iana-status-codes ?>
925</section>
926
927<section title="Header Field Registration" anchor="header.field.registration">
928<t>
929   The Message Header Field Registry located at <eref target="http://www.iana.org/assignments/message-headers/message-header-index.html"/> shall be updated
930   with the permanent registrations below (see <xref target="RFC3864"/>):
931</t>
932<?BEGININC p5-range.iana-headers ?>
933<!--AUTOGENERATED FROM extract-header-defs.xslt, do not edit manually-->
934<texttable align="left" suppress-title="true" anchor="iana.header.registration.table">
935   <ttcol>Header Field Name</ttcol>
936   <ttcol>Protocol</ttcol>
937   <ttcol>Status</ttcol>
938   <ttcol>Reference</ttcol>
939
940   <c>Accept-Ranges</c>
941   <c>http</c>
942   <c>standard</c>
943   <c>
944      <xref target="header.accept-ranges"/>
945   </c>
946   <c>Content-Range</c>
947   <c>http</c>
948   <c>standard</c>
949   <c>
950      <xref target="header.content-range"/>
951   </c>
952   <c>If-Range</c>
953   <c>http</c>
954   <c>standard</c>
955   <c>
956      <xref target="header.if-range"/>
957   </c>
958   <c>Range</c>
959   <c>http</c>
960   <c>standard</c>
961   <c>
962      <xref target="header.range"/>
963   </c>
964</texttable>
965<!--(END)-->
966<?ENDINC p5-range.iana-headers ?>
967<t>
968   The change controller is: "IETF (iesg@ietf.org) - Internet Engineering Task Force".
969</t>
970</section>
971
972<section title="Range Specifier Registration" anchor="range.specifier.registration">
973<t>
974  The registration procedure for HTTP Range Specifiers is defined by
975  <xref target="range.specifier.registry"/> of this document.
976</t>
977<t>
978   The HTTP Range Specifier Registry shall be created at <eref target="http://www.iana.org/assignments/http-range-specifiers"/>
979   and be populated with the registrations below:
980</t>
981<texttable align="left" suppress-title="true" anchor="iana.range.specifiers.table">
982   <ttcol>Range Specifier Name</ttcol>
983   <ttcol>Description</ttcol>
984   <ttcol>Reference</ttcol>
985
986   <c>bytes</c>
987   <c>a range of octets</c>
988   <c>(this specification)</c>
989</texttable>
990<t>
991   The change controller is: "IETF (iesg@ietf.org) - Internet Engineering Task Force".
992</t>
993</section>
994</section>
995
996<section title="Security Considerations" anchor="security.considerations">
997<t>
998   This section is meant to inform application developers, information
999   providers, and users of the security limitations in HTTP/1.1 as
1000   described by this document. The discussion does not include
1001   definitive solutions to the problems revealed, though it does make
1002   some suggestions for reducing security risks.
1003</t>
1004<section title="Overlapping Ranges" anchor="overlapping.ranges">
1005<t>
1006   Range requests containing overlapping ranges may lead to the situation
1007   where a server is sending far more data than the size of the complete
1008   resource representation.
1009</t>
1010</section>
1011</section>
1012
1013<section title="Acknowledgments" anchor="acks">
1014<t>
1015  See &acks;.
1016</t>
1017</section>
1018</middle>
1019<back>
1020
1021<references title="Normative References">
1022
1023<reference anchor="Part1">
1024  <front>
1025    <title abbrev="HTTP/1.1">HTTP/1.1, part 1: URIs, Connections, and Message Parsing</title>
1026    <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
1027      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1028      <address><email>fielding@gbiv.com</email></address>
1029    </author>
1030    <author initials="J." surname="Gettys" fullname="Jim Gettys">
1031      <organization abbrev="Alcatel-Lucent">Alcatel-Lucent Bell Labs</organization>
1032      <address><email>jg@freedesktop.org</email></address>
1033    </author>
1034    <author initials="J." surname="Mogul" fullname="Jeffrey C. Mogul">
1035      <organization abbrev="HP">Hewlett-Packard Company</organization>
1036      <address><email>JeffMogul@acm.org</email></address>
1037    </author>
1038    <author initials="H." surname="Frystyk" fullname="Henrik Frystyk Nielsen">
1039      <organization abbrev="Microsoft">Microsoft Corporation</organization>
1040      <address><email>henrikn@microsoft.com</email></address>
1041    </author>
1042    <author initials="L." surname="Masinter" fullname="Larry Masinter">
1043      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1044      <address><email>LMM@acm.org</email></address>
1045    </author>
1046    <author initials="P." surname="Leach" fullname="Paul J. Leach">
1047      <organization abbrev="Microsoft">Microsoft Corporation</organization>
1048      <address><email>paulle@microsoft.com</email></address>
1049    </author>
1050    <author initials="T." surname="Berners-Lee" fullname="Tim Berners-Lee">
1051      <organization abbrev="W3C/MIT">World Wide Web Consortium</organization>
1052      <address><email>timbl@w3.org</email></address>
1053    </author>
1054    <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
1055      <organization abbrev="W3C">World Wide Web Consortium</organization>
1056      <address><email>ylafon@w3.org</email></address>
1057    </author>
1058    <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
1059      <organization abbrev="greenbytes">greenbytes GmbH</organization>
1060      <address><email>julian.reschke@greenbytes.de</email></address>
1061    </author>
1062    <date month="&ID-MONTH;" year="&ID-YEAR;"/>
1063  </front>
1064  <seriesInfo name="Internet-Draft" value="draft-ietf-httpbis-p1-messaging-&ID-VERSION;"/>
1065  <x:source href="p1-messaging.xml" basename="p1-messaging"/>
1066</reference>
1067
1068<reference anchor="Part2">
1069  <front>
1070    <title abbrev="HTTP/1.1">HTTP/1.1, part 2: Message Semantics</title>
1071    <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
1072      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1073      <address><email>fielding@gbiv.com</email></address>
1074    </author>
1075    <author initials="J." surname="Gettys" fullname="Jim Gettys">
1076      <organization abbrev="Alcatel-Lucent">Alcatel-Lucent Bell Labs</organization>
1077      <address><email>jg@freedesktop.org</email></address>
1078    </author>
1079    <author initials="J." surname="Mogul" fullname="Jeffrey C. Mogul">
1080      <organization abbrev="HP">Hewlett-Packard Company</organization>
1081      <address><email>JeffMogul@acm.org</email></address>
1082    </author>
1083    <author initials="H." surname="Frystyk" fullname="Henrik Frystyk Nielsen">
1084      <organization abbrev="Microsoft">Microsoft Corporation</organization>
1085      <address><email>henrikn@microsoft.com</email></address>
1086    </author>
1087    <author initials="L." surname="Masinter" fullname="Larry Masinter">
1088      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1089      <address><email>LMM@acm.org</email></address>
1090    </author>
1091    <author initials="P." surname="Leach" fullname="Paul J. Leach">
1092      <organization abbrev="Microsoft">Microsoft Corporation</organization>
1093      <address><email>paulle@microsoft.com</email></address>
1094    </author>
1095    <author initials="T." surname="Berners-Lee" fullname="Tim Berners-Lee">
1096      <organization abbrev="W3C/MIT">World Wide Web Consortium</organization>
1097      <address><email>timbl@w3.org</email></address>
1098    </author>
1099    <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
1100      <organization abbrev="W3C">World Wide Web Consortium</organization>
1101      <address><email>ylafon@w3.org</email></address>
1102    </author>
1103    <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
1104      <organization abbrev="greenbytes">greenbytes GmbH</organization>
1105      <address><email>julian.reschke@greenbytes.de</email></address>
1106    </author>
1107    <date month="&ID-MONTH;" year="&ID-YEAR;"/>
1108  </front>
1109  <seriesInfo name="Internet-Draft" value="draft-ietf-httpbis-p2-semantics-&ID-VERSION;"/>
1110  <x:source href="p2-semantics.xml" basename="p2-semantics"/>
1111</reference>
1112
1113<reference anchor="Part4">
1114  <front>
1115    <title abbrev="HTTP/1.1">HTTP/1.1, part 4: Conditional Requests</title>
1116    <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
1117      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1118      <address><email>fielding@gbiv.com</email></address>
1119    </author>
1120    <author initials="J." surname="Gettys" fullname="Jim Gettys">
1121      <organization abbrev="Alcatel-Lucent">Alcatel-Lucent Bell Labs</organization>
1122      <address><email>jg@freedesktop.org</email></address>
1123    </author>
1124    <author initials="J." surname="Mogul" fullname="Jeffrey C. Mogul">
1125      <organization abbrev="HP">Hewlett-Packard Company</organization>
1126      <address><email>JeffMogul@acm.org</email></address>
1127    </author>
1128    <author initials="H." surname="Frystyk" fullname="Henrik Frystyk Nielsen">
1129      <organization abbrev="Microsoft">Microsoft Corporation</organization>
1130      <address><email>henrikn@microsoft.com</email></address>
1131    </author>
1132    <author initials="L." surname="Masinter" fullname="Larry Masinter">
1133      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1134      <address><email>LMM@acm.org</email></address>
1135    </author>
1136    <author initials="P." surname="Leach" fullname="Paul J. Leach">
1137      <organization abbrev="Microsoft">Microsoft Corporation</organization>
1138      <address><email>paulle@microsoft.com</email></address>
1139    </author>
1140    <author initials="T." surname="Berners-Lee" fullname="Tim Berners-Lee">
1141      <organization abbrev="W3C/MIT">World Wide Web Consortium</organization>
1142      <address><email>timbl@w3.org</email></address>
1143    </author>
1144    <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
1145      <organization abbrev="W3C">World Wide Web Consortium</organization>
1146      <address><email>ylafon@w3.org</email></address>
1147    </author>
1148    <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
1149      <organization abbrev="greenbytes">greenbytes GmbH</organization>
1150      <address><email>julian.reschke@greenbytes.de</email></address>
1151    </author>
1152    <date month="&ID-MONTH;" year="&ID-YEAR;"/>
1153  </front>
1154  <seriesInfo name="Internet-Draft" value="draft-ietf-httpbis-p4-conditional-&ID-VERSION;"/>
1155  <x:source href="p4-conditional.xml" basename="p4-conditional"/>
1156</reference>
1157
1158<reference anchor="RFC2046">
1159  <front>
1160    <title abbrev="Media Types">Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types</title>
1161    <author initials="N." surname="Freed" fullname="Ned Freed">
1162      <organization>Innosoft International, Inc.</organization>
1163      <address><email>ned@innosoft.com</email></address>
1164    </author>
1165    <author initials="N." surname="Borenstein" fullname="Nathaniel S. Borenstein">
1166      <organization>First Virtual Holdings</organization>
1167      <address><email>nsb@nsb.fv.com</email></address>
1168    </author>
1169    <date month="November" year="1996"/>
1170  </front>
1171  <seriesInfo name="RFC" value="2046"/>
1172</reference>
1173
1174<reference anchor="RFC2119">
1175  <front>
1176    <title>Key words for use in RFCs to Indicate Requirement Levels</title>
1177    <author initials="S." surname="Bradner" fullname="Scott Bradner">
1178      <organization>Harvard University</organization>
1179      <address><email>sob@harvard.edu</email></address>
1180    </author>
1181    <date month="March" year="1997"/>
1182  </front>
1183  <seriesInfo name="BCP" value="14"/>
1184  <seriesInfo name="RFC" value="2119"/>
1185</reference>
1186
1187<reference anchor="RFC5234">
1188  <front>
1189    <title abbrev="ABNF for Syntax Specifications">Augmented BNF for Syntax Specifications: ABNF</title>
1190    <author initials="D." surname="Crocker" fullname="Dave Crocker" role="editor">
1191      <organization>Brandenburg InternetWorking</organization>
1192      <address>
1193        <email>dcrocker@bbiw.net</email>
1194      </address> 
1195    </author>
1196    <author initials="P." surname="Overell" fullname="Paul Overell">
1197      <organization>THUS plc.</organization>
1198      <address>
1199        <email>paul.overell@thus.net</email>
1200      </address>
1201    </author>
1202    <date month="January" year="2008"/>
1203  </front>
1204  <seriesInfo name="STD" value="68"/>
1205  <seriesInfo name="RFC" value="5234"/>
1206</reference>
1207
1208</references>
1209
1210<references title="Informative References">
1211
1212<reference anchor="RFC2616">
1213  <front>
1214    <title>Hypertext Transfer Protocol -- HTTP/1.1</title>
1215    <author initials="R." surname="Fielding" fullname="R. Fielding">
1216      <organization>University of California, Irvine</organization>
1217      <address><email>fielding@ics.uci.edu</email></address>
1218    </author>
1219    <author initials="J." surname="Gettys" fullname="J. Gettys">
1220      <organization>W3C</organization>
1221      <address><email>jg@w3.org</email></address>
1222    </author>
1223    <author initials="J." surname="Mogul" fullname="J. Mogul">
1224      <organization>Compaq Computer Corporation</organization>
1225      <address><email>mogul@wrl.dec.com</email></address>
1226    </author>
1227    <author initials="H." surname="Frystyk" fullname="H. Frystyk">
1228      <organization>MIT Laboratory for Computer Science</organization>
1229      <address><email>frystyk@w3.org</email></address>
1230    </author>
1231    <author initials="L." surname="Masinter" fullname="L. Masinter">
1232      <organization>Xerox Corporation</organization>
1233      <address><email>masinter@parc.xerox.com</email></address>
1234    </author>
1235    <author initials="P." surname="Leach" fullname="P. Leach">
1236      <organization>Microsoft Corporation</organization>
1237      <address><email>paulle@microsoft.com</email></address>
1238    </author>
1239    <author initials="T." surname="Berners-Lee" fullname="T. Berners-Lee">
1240      <organization>W3C</organization>
1241      <address><email>timbl@w3.org</email></address>
1242    </author>
1243    <date month="June" year="1999"/>
1244  </front>
1245  <seriesInfo name="RFC" value="2616"/>
1246</reference>
1247
1248<reference anchor='RFC3864'>
1249  <front>
1250    <title>Registration Procedures for Message Header Fields</title>
1251    <author initials='G.' surname='Klyne' fullname='G. Klyne'>
1252      <organization>Nine by Nine</organization>
1253      <address><email>GK-IETF@ninebynine.org</email></address>
1254    </author>
1255    <author initials='M.' surname='Nottingham' fullname='M. Nottingham'>
1256      <organization>BEA Systems</organization>
1257      <address><email>mnot@pobox.com</email></address>
1258    </author>
1259    <author initials='J.' surname='Mogul' fullname='J. Mogul'>
1260      <organization>HP Labs</organization>
1261      <address><email>JeffMogul@acm.org</email></address>
1262    </author>
1263    <date year='2004' month='September' />
1264  </front>
1265  <seriesInfo name='BCP' value='90' />
1266  <seriesInfo name='RFC' value='3864' />
1267</reference>
1268
1269<reference anchor="RFC4288">
1270  <front>
1271    <title>Media Type Specifications and Registration Procedures</title>
1272    <author initials="N." surname="Freed" fullname="N. Freed">
1273      <organization>Sun Microsystems</organization>
1274      <address>
1275        <email>ned.freed@mrochek.com</email>
1276      </address>
1277    </author>
1278    <author initials="J." surname="Klensin" fullname="J. Klensin">
1279      <address>
1280        <email>klensin+ietf@jck.com</email>
1281      </address>
1282    </author>
1283    <date year="2005" month="December"/>
1284  </front>
1285  <seriesInfo name="BCP" value="13"/>
1286  <seriesInfo name="RFC" value="4288"/>
1287</reference>
1288
1289<reference anchor='RFC5226'>
1290  <front>
1291    <title>Guidelines for Writing an IANA Considerations Section in RFCs</title>
1292    <author initials='T.' surname='Narten' fullname='T. Narten'>
1293      <organization>IBM</organization>
1294      <address><email>narten@us.ibm.com</email></address>
1295    </author>
1296    <author initials='H.' surname='Alvestrand' fullname='H. Alvestrand'>
1297      <organization>Google</organization>
1298      <address><email>Harald@Alvestrand.no</email></address>
1299    </author>
1300    <date year='2008' month='May' />
1301  </front>
1302  <seriesInfo name='BCP' value='26' />
1303  <seriesInfo name='RFC' value='5226' />
1304</reference>
1305
1306</references>
1307
1308<section title="Internet Media Type multipart/byteranges" anchor="internet.media.type.multipart.byteranges">
1309<iref item="Media Type" subitem="multipart/byteranges" primary="true"/>
1310<iref item="multipart/byteranges Media Type" primary="true"/>
1311<t>
1312   When an HTTP 206 (Partial Content) response message includes the
1313   content of multiple ranges (a response to a request for multiple
1314   non-overlapping ranges), these are transmitted as a multipart
1315   message-body (<xref target="RFC2046" x:fmt="," x:sec="5.1"/>). The media type for this purpose is called
1316   "multipart/byteranges".  The following is to be registered with IANA <xref target="RFC4288"/>.
1317</t>
1318<x:note>
1319  <t>
1320    <x:h>Note:</x:h> Despite the name "multipart/byteranges" is not limited to the byte ranges only.
1321  </t>
1322</x:note>
1323<t>
1324   The multipart/byteranges media type includes one or more parts, each
1325   with its own Content-Type and Content-Range fields. The required
1326   boundary parameter specifies the boundary string used to separate
1327   each body-part.
1328</t>
1329<t>
1330  <list style="hanging" x:indent="12em">
1331    <t hangText="Type name:">
1332      multipart
1333    </t>
1334    <t hangText="Subtype name:">
1335      byteranges
1336    </t>
1337    <t hangText="Required parameters:">
1338      boundary
1339    </t>
1340    <t hangText="Optional parameters:">
1341      none
1342    </t>
1343    <t hangText="Encoding considerations:">
1344      only "7bit", "8bit", or "binary" are permitted
1345    </t>
1346    <t hangText="Security considerations:">
1347      none
1348    </t>
1349    <t hangText="Interoperability considerations:">
1350      none
1351    </t>
1352    <t hangText="Published specification:">
1353      This specification (see <xref target="internet.media.type.multipart.byteranges"/>).
1354    </t>
1355    <t hangText="Applications that use this media type:">
1356    </t>
1357    <t hangText="Additional information:">
1358      <list style="hanging">
1359        <t hangText="Magic number(s):">none</t>
1360        <t hangText="File extension(s):">none</t>
1361        <t hangText="Macintosh file type code(s):">none</t>
1362      </list>
1363    </t>
1364    <t hangText="Person and email address to contact for further information:">
1365      See Authors Section.
1366    </t>
1367    <t hangText="Intended usage:">
1368      COMMON
1369    </t>
1370    <t hangText="Restrictions on usage:">
1371      none
1372    </t>
1373    <t hangText="Author/Change controller:">
1374      IESG
1375    </t>
1376  </list>
1377</t>
1378<figure><preamble>
1379   For example:
1380</preamble><artwork type="example">
1381  HTTP/1.1 206 Partial Content
1382  Date: Wed, 15 Nov 1995 06:25:24 GMT
1383  Last-Modified: Wed, 15 Nov 1995 04:58:08 GMT
1384  Content-type: multipart/byteranges; boundary=THIS_STRING_SEPARATES
1385 
1386  --THIS_STRING_SEPARATES
1387  Content-type: application/pdf
1388  Content-range: bytes 500-999/8000
1389 
1390  ...the first range...
1391  --THIS_STRING_SEPARATES
1392  Content-type: application/pdf
1393  Content-range: bytes 7000-7999/8000
1394 
1395  ...the second range
1396  --THIS_STRING_SEPARATES--
1397</artwork></figure>
1398<figure><preamble>
1399   Other example:
1400</preamble>
1401<artwork type="example">
1402  HTTP/1.1 206 Partial Content
1403  Date: Tue, 14 Nov 1995 06:25:24 GMT
1404  Last-Modified: Tue, 14 July 04:58:08 GMT
1405  Content-type: multipart/byteranges; boundary=THIS_STRING_SEPARATES
1406 
1407  --THIS_STRING_SEPARATES
1408  Content-type: video/example
1409  Content-range: exampleunit 1.2-4.3/25
1410 
1411  ...the first range...
1412  --THIS_STRING_SEPARATES
1413  Content-type: video/example
1414  Content-range: exampleunit 11.2-14.3/25
1415 
1416  ...the second range
1417  --THIS_STRING_SEPARATES--
1418</artwork>
1419</figure>
1420<t>
1421      Notes:
1422  <list style="numbers">
1423      <t>Additional CRLFs &MAY; precede the first boundary string in the body.</t>
1424
1425      <t>Although <xref target="RFC2046"/> permits the boundary string to be
1426         quoted, some existing implementations handle a quoted boundary
1427         string incorrectly.</t>
1428
1429      <t>A number of browsers and servers were coded to an early draft
1430         of the byteranges specification to use a media type of
1431         multipart/x-byteranges<iref item="multipart/x-byteranges Media Type"/><iref item="Media Type" subitem="multipart/x-byteranges"/>, which is almost, but not quite
1432         compatible with the version documented in HTTP/1.1.</t>
1433  </list>
1434</t>
1435</section>
1436
1437<section title="Compatibility with Previous Versions" anchor="compatibility">
1438<section title="Changes from RFC 2616" anchor="changes.from.rfc.2616">
1439<t>
1440  Clarify that it is not ok to use a weak validator in a 206 response.
1441  (<xref target="status.206"/>)
1442</t>
1443<t>
1444  Change ABNF productions for header fields to only define the field value.
1445  (<xref target="header.field.definitions"/>)
1446</t>
1447<t>
1448  Clarify that multipart/byteranges can consist of a single part.
1449  (<xref target="internet.media.type.multipart.byteranges"/>)
1450</t>
1451</section>
1452
1453</section>
1454
1455<?BEGININC p5-range.abnf-appendix ?>
1456<section xmlns:x="http://purl.org/net/xml2rfc/ext" title="Collected ABNF" anchor="collected.abnf">
1457<figure>
1458<artwork type="abnf" name="p5-range.parsed-abnf">
1459<x:ref>Accept-Ranges</x:ref> = acceptable-ranges
1460
1461<x:ref>Content-Range</x:ref> = byte-content-range-spec / other-content-range-spec
1462
1463<x:ref>HTTP-date</x:ref> = &lt;HTTP-date, defined in [Part2], Section 8&gt;
1464
1465<x:ref>If-Range</x:ref> = entity-tag / HTTP-date
1466
1467<x:ref>OWS</x:ref> = &lt;OWS, defined in [Part1], Section 1.2.2&gt;
1468
1469<x:ref>Range</x:ref> = byte-ranges-specifier / other-ranges-specifier
1470
1471<x:ref>acceptable-ranges</x:ref> = ( *( "," OWS ) range-unit *( OWS "," [ OWS
1472 range-unit ] ) ) / "none"
1473
1474<x:ref>byte-content-range-spec</x:ref> = bytes-unit SP byte-range-resp-spec "/" (
1475 instance-length / "*" )
1476<x:ref>byte-range-resp-spec</x:ref> = ( first-byte-pos "-" last-byte-pos ) / "*"
1477<x:ref>byte-range-set</x:ref> = ( *( "," OWS ) byte-range-spec ) / (
1478 suffix-byte-range-spec *( OWS "," [ ( OWS byte-range-spec ) /
1479 suffix-byte-range-spec ] ) )
1480<x:ref>byte-range-spec</x:ref> = first-byte-pos "-" [ last-byte-pos ]
1481<x:ref>byte-ranges-specifier</x:ref> = bytes-unit "=" byte-range-set
1482<x:ref>bytes-unit</x:ref> = "bytes"
1483
1484<x:ref>entity-tag</x:ref> = &lt;entity-tag, defined in [Part4], Section 2.3&gt;
1485
1486<x:ref>first-byte-pos</x:ref> = 1*DIGIT
1487
1488<x:ref>instance-length</x:ref> = 1*DIGIT
1489
1490<x:ref>last-byte-pos</x:ref> = 1*DIGIT
1491
1492<x:ref>other-content-range-spec</x:ref> = other-range-unit SP other-range-resp-spec
1493<x:ref>other-range-resp-spec</x:ref> = *CHAR
1494<x:ref>other-range-set</x:ref> = 1*CHAR
1495<x:ref>other-range-unit</x:ref> = token
1496<x:ref>other-ranges-specifier</x:ref> = other-range-unit "=" other-range-set
1497
1498<x:ref>range-unit</x:ref> = bytes-unit / other-range-unit
1499
1500<x:ref>suffix-byte-range-spec</x:ref> = "-" suffix-length
1501<x:ref>suffix-length</x:ref> = 1*DIGIT
1502
1503<x:ref>token</x:ref> = &lt;token, defined in [Part1], Section 3.2.3&gt;
1504</artwork>
1505</figure>
1506<figure><preamble>ABNF diagnostics:</preamble><artwork type="inline">
1507; Accept-Ranges defined but not used
1508; Content-Range defined but not used
1509; If-Range defined but not used
1510; Range defined but not used
1511</artwork></figure></section>
1512<?ENDINC p5-range.abnf-appendix ?>
1513
1514
1515<section title="Change Log (to be removed by RFC Editor before publication)" anchor="change.log">
1516
1517<section title="Since RFC 2616">
1518<t>
1519  Extracted relevant partitions from <xref target="RFC2616"/>.
1520</t>
1521</section>
1522
1523<section title="Since draft-ietf-httpbis-p5-range-00">
1524<t>
1525  Closed issues:
1526  <list style="symbols"> 
1527    <t>
1528      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/18"/>:
1529      "Cache validators in 206 responses"
1530      (<eref target="http://purl.org/NET/http-errata#ifrange206"/>)
1531    </t>
1532    <t>
1533      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/35"/>:
1534      "Normative and Informative references"
1535    </t>
1536    <t>
1537      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/86"/>:
1538      "Normative up-to-date references"
1539    </t>
1540  </list>
1541</t>
1542</section>
1543
1544<section title="Since draft-ietf-httpbis-p5-range-01">
1545<t>
1546  Closed issues:
1547  <list style="symbols"> 
1548    <t>
1549      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/55"/>:
1550      "Updating to RFC4288"
1551    </t>
1552  </list>
1553</t>
1554<t>
1555  Ongoing work on ABNF conversion (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/36"/>):
1556  <list style="symbols"> 
1557    <t>
1558      Add explicit references to BNF syntax and rules imported from other parts of the specification.
1559    </t>
1560  </list>
1561</t>
1562</section>
1563
1564<section title="Since draft-ietf-httpbis-p5-range-02" anchor="changes.since.02">
1565<t>
1566  Ongoing work on IANA Message Header Field Registration (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/40"/>):
1567  <list style="symbols"> 
1568    <t>
1569      Reference RFC 3984, and update header field registrations for headers defined
1570      in this document.
1571    </t>
1572  </list>
1573</t>
1574</section>
1575
1576<section title="Since draft-ietf-httpbis-p5-range-03" anchor="changes.since.03">
1577<t>
1578  None.
1579</t>
1580</section>
1581
1582<section title="Since draft-ietf-httpbis-p5-range-04" anchor="changes.since.04">
1583<t>
1584  Closed issues:
1585  <list style="symbols"> 
1586    <t>
1587      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/133"/>:
1588      "multipart/byteranges minimum number of parts"
1589    </t>
1590  </list>
1591</t>
1592<t>
1593  Ongoing work on ABNF conversion (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/36"/>):
1594  <list style="symbols"> 
1595    <t>
1596      Use "/" instead of "|" for alternatives.
1597    </t>
1598    <t>
1599      Introduce new ABNF rules for "bad" whitespace ("BWS"), optional
1600      whitespace ("OWS") and required whitespace ("RWS").
1601    </t>
1602    <t>
1603      Rewrite ABNFs to spell out whitespace rules, factor out
1604      header field value format definitions.
1605    </t>
1606  </list>
1607</t>
1608</section>
1609
1610<section title="Since draft-ietf-httpbis-p5-range-05" anchor="changes.since.05">
1611<t>
1612  Closed issues:
1613  <list style="symbols"> 
1614    <t>
1615      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/142"/>:
1616      "State base for *-byte-pos and suffix-length"
1617    </t>
1618  </list>
1619</t>
1620<t>
1621  Ongoing work on Custom Ranges (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/85"/>):
1622  <list style="symbols"> 
1623    <t>
1624      Remove bias in favor of byte ranges; allow custom ranges in ABNF.
1625    </t>
1626  </list>
1627</t>
1628<t>
1629  Final work on ABNF conversion (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/36"/>):
1630  <list style="symbols"> 
1631    <t>
1632      Add appendix containing collected and expanded ABNF, reorganize ABNF introduction.
1633    </t>
1634  </list>
1635</t>
1636</section>
1637
1638<section title="Since draft-ietf-httpbis-p5-range-06" anchor="changes.since.06">
1639<t>
1640  Closed issues:
1641  <list style="symbols"> 
1642    <t>
1643      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/161"/>:
1644      "base for numeric protocol elements"
1645    </t>
1646  </list>
1647</t>
1648</section>
1649
1650<section title="Since draft-ietf-httpbis-p5-range-07" anchor="changes.since.07">
1651<t>
1652  Closed issues:
1653  <list style="symbols">
1654    <t>
1655      Fixed discrepancy in the If-Range definition about allowed validators.
1656    </t>
1657    <t>
1658      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/150" />: "multipart/byteranges for custom range units"
1659    </t>
1660    <t>
1661      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/151" />: "range unit missing from other-ranges-specifier in Range header"
1662    </t>
1663    <t>
1664      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/198"/>:
1665      "move IANA registrations for optional status codes"
1666    </t>
1667  </list>
1668</t>
1669</section>
1670
1671<section title="Since draft-ietf-httpbis-p5-range-08" anchor="changes.since.08">
1672<t>
1673  No significant changes.
1674</t>
1675</section>
1676
1677<section title="Since draft-ietf-httpbis-p5-range-09" anchor="changes.since.09">
1678<t>
1679 No significant changes.
1680</t>
1681</section>
1682
1683<section title="Since draft-ietf-httpbis-p5-range-10" anchor="changes.since.10">
1684<t>
1685  Closed issues:
1686  <list style="symbols"> 
1687    <t>
1688      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/69"/>:
1689      "Clarify 'Requested Variant'"
1690    </t>
1691    <t>
1692      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/109"/>:
1693      "Clarify entity / representation / variant terminology"
1694    </t>
1695    <t>
1696      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/220"/>:
1697      "consider removing the 'changes from 2068' sections"
1698    </t>
1699  </list>
1700</t>
1701<t>
1702  Ongoing work on Custom Ranges (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/85"/>):
1703  <list style="symbols"> 
1704    <t>
1705      Add IANA registry.
1706    </t>
1707  </list>
1708</t>
1709</section>
1710
1711<section title="Since draft-ietf-httpbis-p5-range-11" anchor="changes.since.11">
1712<t>
1713  Closed issues:
1714  <list style="symbols"> 
1715    <t>
1716      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/217"/>:
1717      "Caches can't be required to serve ranges"
1718    </t>
1719  </list>
1720</t>
1721</section>
1722
1723<section title="Since draft-ietf-httpbis-p5-range-12" anchor="changes.since.12">
1724<t>
1725  Closed issues:
1726  <list style="symbols"> 
1727    <t>
1728      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/224"/>:
1729      "Header Classification"
1730    </t>
1731  </list>
1732</t>
1733</section>
1734
1735<section title="Since draft-ietf-httpbis-p5-range-13" anchor="changes.since.13">
1736<t>
1737  Closed issues:
1738  <list style="symbols">
1739    <t>
1740      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/276"/>:
1741      "untangle ABNFs for header fields"
1742    </t>
1743  </list>
1744</t>
1745</section>
1746
1747<section title="Since draft-ietf-httpbis-p5-range-14" anchor="changes.since.14">
1748<t>
1749  None.
1750</t>
1751</section>
1752
1753<section title="Since draft-ietf-httpbis-p5-range-15" anchor="changes.since.15">
1754<t>
1755  Closed issues:
1756  <list style="symbols">
1757    <t>
1758      <eref target="http://trac.tools.ietf.org/wg/httpbis/trac/ticket/175"/>:
1759      "Security consideration: range flooding"
1760    </t>
1761  </list>
1762</t>
1763</section>
1764
1765<section title="Since draft-ietf-httpbis-p5-range-16" anchor="changes.since.16">
1766<t>
1767  None yet.
1768</t>
1769</section>
1770
1771</section>
1772
1773</back>
1774</rfc>
Note: See TracBrowser for help on using the repository browser.