source: draft-ietf-httpbis/latest/p5-range.xml @ 1739

Last change on this file since 1739 was 1739, checked in by julian.reschke@…, 7 years ago

Work-in-progress: hyperlink header field definitions(P4)

  • Property svn:eol-style set to native
  • Property svn:mime-type set to text/xml
File size: 66.8 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 "July">
16  <!ENTITY ID-YEAR "2012">
17  <!ENTITY Note "<x:h xmlns:x='http://purl.org/net/xml2rfc/ext'>Note:</x:h>">
18  <!ENTITY architecture               "<xref target='Part1' x:rel='#architecture' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
19  <!ENTITY notation                   "<xref target='Part1' x:rel='#notation' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
20  <!ENTITY abnf-extension             "<xref target='Part1' x:rel='#abnf.extension' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
21  <!ENTITY acks                       "<xref target='Part1' x:rel='#acks' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
22  <!ENTITY whitespace                 "<xref target='Part1' x:rel='#whitespace' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
23  <!ENTITY field-components           "<xref target='Part1' x:rel='#field.components' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
24  <!ENTITY http-date                  "<xref target='Part2' x:rel='#http.date' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
25  <!ENTITY messaging                  "<xref target='Part1' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
26  <!ENTITY entity-tags                "<xref target='Part4' x:rel='#header.etag' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
27  <!ENTITY weak-and-strong-validators "<xref target='Part4' x:rel='#weak.and.strong.validators' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
28  <!ENTITY lastmod-comparison         "<xref target='Part4' x:rel='#lastmod.comparison' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
29  <!ENTITY p6-heuristic               "<xref target='Part6' x:rel='#heuristic.freshness' xmlns:x='http://purl.org/net/xml2rfc/ext'/>">
30]>
31<?rfc toc="yes" ?>
32<?rfc symrefs="yes" ?>
33<?rfc sortrefs="yes" ?>
34<?rfc compact="yes"?>
35<?rfc subcompact="no" ?>
36<?rfc linkmailto="no" ?>
37<?rfc editing="no" ?>
38<?rfc comments="yes"?>
39<?rfc inline="yes"?>
40<?rfc rfcedstyle="yes"?>
41<?rfc-ext allow-markup-in-artwork="yes" ?>
42<?rfc-ext include-references-in-index="yes" ?>
43<rfc obsoletes="2616" category="std" x:maturity-level="proposed"
44     ipr="pre5378Trust200902" docName="draft-ietf-httpbis-p5-range-&ID-VERSION;"
45     xmlns:x='http://purl.org/net/xml2rfc/ext'>
46<x:link rel="prev" basename="p4-conditional"/>
47<x:link rel="next" basename="p6-cache"/>
48<x:feedback template="mailto:ietf-http-wg@w3.org?subject={docname},%20%22{section}%22&amp;body=&lt;{ref}&gt;:"/>
49<front>
50
51  <title abbrev="HTTP/1.1, Part 5">HTTP/1.1, part 5: Range Requests and Partial Responses</title>
52
53  <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
54    <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
55    <address>
56      <postal>
57        <street>345 Park Ave</street>
58        <city>San Jose</city>
59        <region>CA</region>
60        <code>95110</code>
61        <country>USA</country>
62      </postal>
63      <email>fielding@gbiv.com</email>
64      <uri>http://roy.gbiv.com/</uri>
65    </address>
66  </author>
67
68  <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
69    <organization abbrev="W3C">World Wide Web Consortium</organization>
70    <address>
71      <postal>
72        <street>W3C / ERCIM</street>
73        <street>2004, rte des Lucioles</street>
74        <city>Sophia-Antipolis</city>
75        <region>AM</region>
76        <code>06902</code>
77        <country>France</country>
78      </postal>
79      <email>ylafon@w3.org</email>
80      <uri>http://www.raubacapeu.net/people/yves/</uri>
81    </address>
82  </author>
83
84  <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
85    <organization abbrev="greenbytes">greenbytes GmbH</organization>
86    <address>
87      <postal>
88        <street>Hafenweg 16</street>
89        <city>Muenster</city><region>NW</region><code>48155</code>
90        <country>Germany</country>
91      </postal>
92      <email>julian.reschke@greenbytes.de</email>
93      <uri>http://greenbytes.de/tech/webdav/</uri>
94    </address>
95  </author>
96
97  <date month="&ID-MONTH;" year="&ID-YEAR;"/>
98  <workgroup>HTTPbis Working Group</workgroup>
99
100<abstract>
101<t>
102   The Hypertext Transfer Protocol (HTTP) is an application-level protocol for
103   distributed, collaborative, hypertext information systems. HTTP has been in
104   use by the World Wide Web global information initiative since 1990. This
105   document is Part 5 of the seven-part specification that defines the protocol
106   referred to as "HTTP/1.1" and, taken together, obsoletes RFC 2616.
107</t>
108<t>
109   Part 5 defines range requests and the rules for constructing and
110   combining responses to those requests.
111</t>
112</abstract>
113
114<note title="Editorial Note (To be removed by RFC Editor)">
115  <t>
116    Discussion of this draft ought to take place on the HTTPBIS working group
117    mailing list (ietf-http-wg@w3.org), which is archived at
118    <eref target="http://lists.w3.org/Archives/Public/ietf-http-wg/"/>.
119  </t>
120  <t>
121    The current issues list is at
122    <eref target="http://tools.ietf.org/wg/httpbis/trac/report/3"/> and related
123    documents (including fancy diffs) can be found at
124    <eref target="http://tools.ietf.org/wg/httpbis/"/>.
125  </t>
126  <t>
127    The changes in this draft are summarized in <xref target="changes.since.19"/>.
128  </t>
129</note>
130</front>
131<middle>
132<section title="Introduction" anchor="introduction">
133<t>
134   HTTP clients often encounter interrupted data transfers as a result
135   of cancelled requests or dropped connections.  When a client has stored
136   a partial representation, it is desirable to request the remainder
137   of that representation in a subsequent request rather than transfer
138   the entire representation.
139   There are also a number of Web applications that benefit from being
140   able to request only a subset of a larger representation, such as a
141   single page of a very large document or only part of an image to be
142   rendered by a device with limited local storage.
143</t>
144<t>
145   This document defines HTTP/1.1 range requests,
146   partial responses, and the multipart/byteranges media type.
147   The protocol for range requests is an &OPTIONAL; feature of HTTP,
148   designed so resources or recipients that do not implement this feature
149   can respond as if it is a normal GET request without impacting
150   interoperability.  Partial responses are indicated by a distinct status
151   code to not be mistaken for full responses by intermediate caches
152   that might not implement the feature.
153</t>
154<t>
155   Although the HTTP range request mechanism is designed to allow for
156   extensible range types, this specification only defines requests for
157   byte ranges.
158</t>
159
160<section title="Conformance and Error Handling" anchor="intro.conformance.and.error.handling">
161<t>
162   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
163   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
164   document are to be interpreted as described in <xref target="RFC2119"/>.
165</t>
166<t>
167   This document defines conformance criteria for several roles in HTTP
168   communication, including Senders, Recipients, Clients, Servers, User-Agents,
169   Origin Servers, Intermediaries, Proxies and Gateways. See &architecture;
170   for definitions of these terms.
171</t>
172<t>
173   An implementation is considered conformant if it complies with all of the
174   requirements associated with its role(s). Note that SHOULD-level requirements
175   are relevant here, unless one of the documented exceptions is applicable.
176</t>
177<t>
178   This document also uses ABNF to define valid protocol elements
179   (<xref target="notation"/>). In addition to the prose requirements placed
180   upon them, Senders &MUST-NOT; generate protocol elements that are invalid.
181</t>
182<t>
183   Unless noted otherwise, Recipients &MUST; be able to parse all protocol
184   elements matching the ABNF rules defined for them and &MAY; take steps to
185   recover a usable protocol element from an invalid construct. However, HTTP does not define
186   specific error handling mechanisms, except in cases where it has direct
187   impact on security. This is because different uses of the protocol require
188   different error handling strategies; for example, a Web browser might wish to
189   transparently recover from a response where the Location header field
190   doesn't parse according to the ABNF, whereby in a systems control protocol
191   using HTTP, this type of error recovery could lead to dangerous consequences.
192</t>
193</section>
194
195<section title="Syntax Notation" anchor="notation">
196  <x:anchor-alias value="ALPHA"/>
197  <x:anchor-alias value="CHAR"/>
198  <x:anchor-alias value="CR"/>
199  <x:anchor-alias value="DIGIT"/>
200  <x:anchor-alias value="LF"/>
201  <x:anchor-alias value="OCTET"/>
202  <x:anchor-alias value="SP"/>
203  <x:anchor-alias value="VCHAR"/>
204<t>
205   This specification uses the Augmented Backus-Naur Form (ABNF) notation
206   of <xref target="RFC5234"/> with the list rule extension defined in
207   &notation;<xref target="collected.abnf"/> shows the collected ABNF
208   with the list rule expanded.
209</t>
210<t>
211  The following core rules are included by
212  reference, as defined in <xref target="RFC5234" x:fmt="," x:sec="B.1"/>:
213  ALPHA (letters), CR (carriage return), CRLF (CR LF), CTL (controls),
214  DIGIT (decimal 0-9), DQUOTE (double quote),
215  HEXDIG (hexadecimal 0-9/A-F/a-f), LF (line feed),
216  OCTET (any 8-bit sequence of data), SP (space), and
217  VCHAR (any visible US-ASCII character).
218</t>
219
220<t>
221  Note that all rules derived from <x:ref>token</x:ref> are to
222  be compared case-insensitively, like <x:ref>range-unit</x:ref> and
223  <x:ref>acceptable-ranges</x:ref>.
224</t>
225
226<section title="Core Rules" anchor="core.rules">
227  <x:anchor-alias value="token"/>
228  <x:anchor-alias value="OWS"/>
229  <x:anchor-alias value="HTTP-date"/>
230<t>
231  The core rules below are defined in <xref target="Part1"/> and
232  <xref target="Part2"/>:
233</t>
234<figure><artwork type="abnf2616">
235  <x:ref>OWS</x:ref>        = &lt;OWS, defined in &whitespace;&gt;
236  <x:ref>token</x:ref>      = &lt;token, defined in &field-components;&gt;
237  <x:ref>HTTP-date</x:ref>  = &lt;HTTP-date, defined in &http-date;&gt;
238</artwork></figure>
239</section>
240
241<section title="ABNF Rules defined in other Parts of the Specification" anchor="abnf.dependencies">
242  <x:anchor-alias value="entity-tag"/>
243<t>
244  The ABNF rules below are defined in other parts:
245</t>
246<figure><!--Part4--><artwork type="abnf2616">
247  <x:ref>entity-tag</x:ref> = &lt;entity-tag, defined in &entity-tags;&gt;
248</artwork></figure>
249</section>
250
251</section>
252
253</section>
254
255
256<section title="Range Units" anchor="range.units">
257  <x:anchor-alias value="bytes-unit"/>
258  <x:anchor-alias value="other-range-unit"/>
259  <x:anchor-alias value="range-unit"/>
260<t>
261   HTTP/1.1 allows a client to request that only part (a range) of the
262   representation be included within the response. HTTP/1.1 uses range
263   units in the <x:ref>Range</x:ref> (<xref target="header.range"/>) and
264   <x:ref>Content-Range</x:ref> (<xref target="header.content-range"/>)
265   header fields. A representation can be broken down into subranges according
266   to various structural units.
267</t>
268<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"/>
269  <x:ref>range-unit</x:ref>       = <x:ref>bytes-unit</x:ref> / <x:ref>other-range-unit</x:ref>
270  <x:ref>bytes-unit</x:ref>       = "bytes"
271  <x:ref>other-range-unit</x:ref> = <x:ref>token</x:ref>
272</artwork></figure>
273<t>
274  HTTP/1.1 has been designed to allow implementations of applications
275  that do not depend on knowledge of ranges. The only range unit defined
276  by HTTP/1.1 is "bytes". Additional specifiers can be defined as described
277  in <xref target="range.specifier.registry"/>.
278</t>
279<t>
280  If a range unit is not understood in a request, a server &MUST; ignore
281  the whole <x:ref>Range</x:ref> header field (<xref target="header.range"/>).
282  If a range unit is not understood in a response, an intermediary
283  &SHOULD; pass the response to the client; a client &MUST; fail.
284</t>
285
286<section title="Range Specifier Registry" anchor="range.specifier.registry">
287<t>
288   The HTTP Range Specifier Registry defines the name space for the range
289   specifier names.
290</t>
291<t>
292   Registrations &MUST; include the following fields:
293   <list style="symbols">
294     <t>Name</t>
295     <t>Description</t>
296     <t>Pointer to specification text</t>
297   </list>
298</t>
299<t>
300  Values to be added to this name space require IETF Review
301  (see <xref target="RFC5226" x:fmt="," x:sec="4.1"/>).
302</t>
303<t>
304   The registry itself is maintained at
305   <eref target="http://www.iana.org/assignments/http-range-specifiers"/>.
306</t>
307</section>
308
309</section>
310
311<section title="Status Code Definitions" anchor="status.code.definitions">
312<section title="206 Partial Content" anchor="status.206">
313  <iref primary="true" item="206 Partial Content (status code)" x:for-anchor=""/>
314  <iref primary="true" item="Status Codes" subitem="206 Partial Content" x:for-anchor=""/>
315  <x:anchor-alias value="206"/>
316  <x:anchor-alias value="206 (Partial Content)"/>
317<t>
318   The server has fulfilled the partial GET request for the resource.
319   The request &MUST; have included a <x:ref>Range</x:ref> header field
320   (<xref target="header.range"/>) indicating the desired range, and &MAY; have
321   included an <x:ref>If-Range</x:ref> header field
322   (<xref target="header.if-range"/>) to make the request conditional.
323</t>
324<t>
325   The response &MUST; include the following header fields:
326  <list style="symbols">
327    <t>
328        Either a <x:ref>Content-Range</x:ref> header field
329        (<xref target="header.content-range"/>) indicating
330        the range included with this response, or a multipart/byteranges
331        Content-Type including Content-Range fields for each part. If a
332        Content-Length header field is present in the response, its
333        value &MUST; match the actual number of octets transmitted in the
334        message body.
335    </t>
336    <t>
337        Date
338    </t>
339    <t>
340        <x:ref>Cache-Control</x:ref>, <x:ref>ETag</x:ref>,
341        <x:ref>Expires</x:ref>, Content-Location and/or
342        <x:ref>Vary</x:ref>, if the header field would have been sent in a
343        <x:ref>200 (OK)</x:ref> response to the same request
344    </t>
345  </list>
346</t>
347<t>
348   If a 206 is sent in response to a request with an <x:ref>If-Range</x:ref>
349   header field, it &SHOULD-NOT; include other representation header fields.
350   Otherwise, the response &MUST; include all of the representation header
351   fields that would have been returned with a <x:ref>200 (OK)</x:ref> response
352   to the same request.
353</t>
354<t>
355   Caches &MAY; use a heuristic (see &p6-heuristic;) to determine
356   freshness for 206 responses.
357</t>
358</section>
359
360<section title="416 Requested Range Not Satisfiable" anchor="status.416">
361  <iref primary="true" item="416 Requested Range Not Satisfiable (status code)" x:for-anchor=""/>
362  <iref primary="true" item="Status Codes" subitem="416 Requested Range Not Satisfiable" x:for-anchor=""/>
363  <x:anchor-alias value="416 (Requested Range Not Satisfiable)"/>
364<t>
365   A server &SHOULD; return a response with this status code if a request
366   included a <x:ref>Range</x:ref> header field (<xref target="header.range"/>),
367   and none of the ranges-specifier values in this field overlap the current
368   extent of the selected resource, and the request did not include an
369   <x:ref>If-Range</x:ref> header field (<xref target="header.if-range"/>).
370   (For byte-ranges, this means that the first-byte-pos of all of the
371   byte-range-spec values were greater than the current length of the selected
372   resource.)
373</t>
374<t>
375   When this status code is returned for a byte-range request, the
376   response &SHOULD; include a <x:ref>Content-Range</x:ref> header field
377   specifying the current length of the representation (see <xref target="header.content-range"/>).
378   This response &MUST-NOT; use the multipart/byteranges content-type. For example,
379</t>
380<figure><artwork type="message/http; msgtype=&#34;response&#34;" x:indent-with="  ">
381HTTP/1.1 416 Requested Range Not Satisfiable
382Date: Mon, 20 Jan 2012 15:41:54 GMT
383Content-Range: bytes */47022
384Content-Type: image/gif
385</artwork></figure>
386<x:note>
387  <t>
388    &Note; Clients cannot depend on servers to send a <x:ref>416 (Requested
389    Range Not Satisfiable)</x:ref> response instead of a <x:ref>200 (OK)</x:ref>
390    response for an unsatisfiable <x:ref>Range</x:ref> header field, since not
391    all servers implement this header field.
392  </t>
393</x:note>
394</section>
395</section>
396
397<section title="Responses to a Range Request">
398<section title="Response to a Single and Multiple Ranges Request">
399<t>
400   When an HTTP message includes the content of a single range (for
401   example, a response to a request for a single range, or to a request
402   for a set of ranges that overlap without any holes), this content is
403   transmitted with a <x:ref>Content-Range</x:ref> header field, and a
404   Content-Length header field showing the number of bytes actually transferred.
405   For example,
406</t>
407<figure><artwork type="message/http; msgtype=&#34;response&#34;" x:indent-with="  ">
408HTTP/1.1 206 Partial Content
409Date: Wed, 15 Nov 1995 06:25:24 GMT
410Last-Modified: Wed, 15 Nov 1995 04:58:08 GMT
411Content-Range: bytes 21010-47021/47022
412Content-Length: 26012
413Content-Type: image/gif
414</artwork></figure>
415<t>
416   When an HTTP message includes the content of multiple ranges (for
417   example, a response to a request for multiple non-overlapping
418   ranges), these are transmitted as a multipart message. The multipart
419   media type used for this purpose is "multipart/byteranges" as defined
420   in <xref target="internet.media.type.multipart.byteranges"/>.
421</t>
422<t>
423   A server &MAY; combine requested ranges when those ranges are overlapping
424   (see <xref target="overlapping.ranges"/>).
425</t>
426<t>
427   A response to a request for a single range &MUST-NOT; be sent using the
428   multipart/byteranges media type.  A response to a request for
429   multiple ranges, whose result is a single range, &MAY; be sent as a
430   multipart/byteranges media type with one part. A client that cannot
431   decode a multipart/byteranges message &MUST-NOT; ask for multiple
432   ranges in a single request.
433</t>
434<t>
435   When a client asks for multiple ranges in one request, the
436   server &SHOULD; return them in the order that they appeared in the
437   request.
438</t>
439</section>
440
441<section title="Combining Ranges" anchor="combining.byte.ranges">
442<t>
443   A response might transfer only a subrange of a representation if the
444   connection closed prematurely or if the request used one or more Range
445   specifications.  After several such transfers, a client might have
446   received several ranges of the same representation.  These ranges can only
447   be safely combined if they all have in common the same strong validator,
448   where "strong validator" is defined to be either an entity-tag that is
449   not marked as weak (&entity-tags;) or, if no entity-tag is provided, a
450   <x:ref>Last-Modified</x:ref> value that is strong in the sense defined by
451   &lastmod-comparison;.
452</t>
453<t>
454   When a client receives an incomplete <x:ref>200 (OK)</x:ref> or <x:ref>206 (Partial Content)</x:ref>
455   response and already has one or more stored responses for the same method
456   and effective request URI, all of the stored responses with the same
457   strong validator &MAY; be combined with the partial content in this new
458   response.  If none of the stored responses contain the same strong
459   validator, then this new response corresponds to a new representation
460   and &MUST-NOT; be combined with the existing stored responses.
461</t>
462<t>
463   If the new response is an incomplete <x:ref>200 (OK)</x:ref> response, then the header
464   fields of that new response are used for any combined response and replace
465   those of the matching stored responses.
466</t>
467<t>
468   If the new response is a <x:ref>206 (Partial Content)</x:ref> response and at least one
469   of the matching stored responses is a <x:ref>200 (OK)</x:ref>, then the combined response
470   header fields consist of the most recent 200 response's header fields.
471   If all of the matching stored responses are 206 responses, then the
472   stored response with the most header fields is used as the source of
473   header fields for the combined response, except that the client &MUST;
474   use other header fields provided in the new response, aside from
475   <x:ref>Content-Range</x:ref>, to replace all instances of the corresponding
476   header fields in the stored response.
477</t>
478<t>
479   The combined response message body consists of the union of partial
480   content ranges in the new response and each of the selected responses.
481   If the union consists of the entire range of the representation, then the
482   combined response &MUST; be recorded as a complete <x:ref>200 (OK)</x:ref> response
483   with a Content-Length header field that reflects the complete length.
484   Otherwise, the combined response(s) &MUST; include a <x:ref>Content-Range</x:ref>
485   header field describing the included range(s) and be recorded as
486   incomplete.  If the union consists of a discontinuous range of the
487   representation, then the client &MAY; store it as either a multipart range
488   response or as multiple <x:ref>206</x:ref> responses with one continuous range each.
489</t>
490</section>
491</section>
492
493<section title="Header Field Definitions" anchor="header.field.definitions">
494<t>
495   This section defines the syntax and semantics of HTTP/1.1 header fields
496   related to range requests and partial responses.
497</t>
498
499<section title="Accept-Ranges" anchor="header.accept-ranges">
500  <iref primary="true" item="Accept-Ranges header field" x:for-anchor=""/>
501  <iref primary="true" item="Header Fields" subitem="Accept-Ranges" x:for-anchor=""/>
502  <x:anchor-alias value="Accept-Ranges"/>
503  <x:anchor-alias value="acceptable-ranges"/>
504<t>
505   The "Accept-Ranges" header field allows a resource to indicate
506   its acceptance of range requests.
507</t>
508<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="Accept-Ranges"/><iref primary="true" item="Grammar" subitem="acceptable-ranges"/>
509  <x:ref>Accept-Ranges</x:ref>     = <x:ref>acceptable-ranges</x:ref>
510  <x:ref>acceptable-ranges</x:ref> = 1#<x:ref>range-unit</x:ref> / "none"
511</artwork></figure>
512<t>
513      Origin servers that accept byte-range requests &MAY; send
514</t>
515<figure><artwork type="example">
516  Accept-Ranges: bytes
517</artwork></figure>
518<t>
519      but are not required to do so. Clients &MAY; generate range
520      requests without having received this header field for the resource
521      involved. Range units are defined in <xref target="range.units"/>.
522</t>
523<t>
524      Servers that do not accept any kind of range request for a
525      resource &MAY; send
526</t>
527<figure><artwork type="example">
528  Accept-Ranges: none
529</artwork></figure>
530<t>
531      to advise the client not to attempt a range request.
532</t>
533</section>
534
535<section title="Content-Range" anchor="header.content-range">
536  <iref primary="true" item="Content-Range header field" x:for-anchor=""/>
537  <iref primary="true" item="Header Fields" subitem="Content-Range" x:for-anchor=""/>
538  <x:anchor-alias value="byte-content-range-spec"/>
539  <x:anchor-alias value="byte-range-resp-spec"/>
540  <x:anchor-alias value="Content-Range"/>
541  <x:anchor-alias value="instance-length"/>
542  <x:anchor-alias value="other-content-range-spec"/>
543  <x:anchor-alias value="other-range-resp-spec"/>
544<t>
545   The "Content-Range" header field is sent with a partial representation to
546   specify where in the full representation the payload body is intended to be
547   applied.
548</t>
549<t>   
550   Range units are defined in <xref target="range.units"/>.
551</t>
552<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"/>
553  <x:ref>Content-Range</x:ref>           = <x:ref>byte-content-range-spec</x:ref>
554                          / <x:ref>other-content-range-spec</x:ref>
555                         
556  <x:ref>byte-content-range-spec</x:ref> = <x:ref>bytes-unit</x:ref> <x:ref>SP</x:ref>
557                            <x:ref>byte-range-resp-spec</x:ref> "/"
558                            ( <x:ref>instance-length</x:ref> / "*" )
559 
560  <x:ref>byte-range-resp-spec</x:ref>    = (<x:ref>first-byte-pos</x:ref> "-" <x:ref>last-byte-pos</x:ref>)
561                          / "*"
562                         
563  <x:ref>instance-length</x:ref>         = 1*<x:ref>DIGIT</x:ref>
564 
565  <x:ref>other-content-range-spec</x:ref> = <x:ref>other-range-unit</x:ref> <x:ref>SP</x:ref>
566                             <x:ref>other-range-resp-spec</x:ref>
567  <x:ref>other-range-resp-spec</x:ref>    = *<x:ref>CHAR</x:ref>
568</artwork></figure>
569<t>
570   The header field &SHOULD; indicate the total length of the full representation,
571   unless this length is unknown or difficult to determine. The asterisk
572   "*" character means that the instance-length is unknown at the time
573   when the response was generated.
574</t>
575<t>
576   Unlike byte-ranges-specifier values (see <xref target="byte.ranges"/>), a byte-range-resp-spec
577   &MUST; only specify one range, and &MUST; contain
578   absolute byte positions for both the first and last byte of the
579   range.
580</t>
581<t>
582   A byte-content-range-spec with a byte-range-resp-spec whose last-byte-pos
583   value is less than its first-byte-pos value, or whose
584   instance-length value is less than or equal to its last-byte-pos
585   value, is invalid. The recipient of an invalid byte-content-range-spec
586   &MUST; ignore it and any content transferred along with it.
587</t>
588<t>
589   In the case of a byte range request:
590   A server sending a response with status code <x:ref>416 (Requested Range Not
591   Satisfiable)</x:ref> &SHOULD; include a Content-Range field with a byte-range-resp-spec
592   of "*". The instance-length specifies the current length of
593   the selected resource. A response with status code <x:ref>206 (Partial Content)</x:ref>
594   &MUST-NOT; include a Content-Range field with a byte-range-resp-spec of "*".
595</t>
596<t>
597  The "Content-Range" header field has no meaning for status codes that do not
598  explicitly describe its semantic. Currently, only status codes
599  <x:ref>206 (Partial Content)</x:ref> and <x:ref>416 (Requested Range Not Satisfiable)</x:ref> describe
600  the meaning of this header field.
601</t>
602<t>
603   Examples of byte-content-range-spec values, assuming that the representation
604   contains a total of 1234 bytes:
605   <list style="symbols">
606      <t>
607        The first 500 bytes:
608<figure><artwork type="example" x:indent-with="   ">
609  bytes 0-499/1234
610</artwork></figure>
611      </t>   
612      <t>
613        The second 500 bytes:
614<figure><artwork type="example" x:indent-with="   ">
615  bytes 500-999/1234
616</artwork></figure>
617      </t>   
618      <t>
619        All except for the first 500 bytes:
620<figure><artwork type="example" x:indent-with="   ">
621  bytes 500-1233/1234
622</artwork></figure>
623      </t>   
624      <t>
625        The last 500 bytes:
626<figure><artwork type="example" x:indent-with="   ">
627  bytes 734-1233/1234
628</artwork></figure>
629      </t>   
630   </list>
631</t>
632<t>
633   If the server ignores a byte-range-spec (for example if it is
634   syntactically invalid, or if it might be seen as a denial-of-service
635   attack), the server &SHOULD; treat the request as if the invalid <x:ref>Range</x:ref>
636   header field did not exist. (Normally, this means return a <x:ref>200 (OK)</x:ref>
637   response containing the full representation).
638</t>
639</section>
640
641<section title="If-Range" anchor="header.if-range">
642  <iref primary="true" item="If-Range header field" x:for-anchor=""/>
643  <iref primary="true" item="Header Fields" subitem="If-Range" x:for-anchor=""/>
644  <x:anchor-alias value="If-Range"/>
645<t>
646   If a client has a partial copy of a representation and wishes
647   to have an up-to-date copy of the entire representation, it could use the
648   <x:ref>Range</x:ref> header field with a conditional GET (using
649   either or both of <x:ref>If-Unmodified-Since</x:ref> and
650   <x:ref>If-Match</x:ref>.) However, if the condition fails because the
651   representation has been modified, the client would then have to make a
652   second request to obtain the entire current representation.
653</t>
654<t>
655   The "If-Range" header field allows a client to "short-circuit" the second
656   request. Informally, its meaning is "if the representation is unchanged, send
657   me the part(s) that I am missing; otherwise, send me the entire new
658   representation".
659</t>
660<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="If-Range"/>
661  <x:ref>If-Range</x:ref> = <x:ref>entity-tag</x:ref> / <x:ref>HTTP-date</x:ref>
662</artwork></figure>
663<t>
664   Clients &MUST-NOT; use an entity-tag marked as weak in an If-Range
665   field value and &MUST-NOT; use a <x:ref>Last-Modified</x:ref> date in an
666   If-Range field value unless it has no entity-tag for the representation and
667   the Last-Modified date it does have for the representation is strong
668   in the sense defined by &lastmod-comparison;.
669</t>
670<t>
671   A server that evaluates a conditional range request that is applicable
672   to one of its representations &MUST; evaluate the condition as false if
673   the entity-tag used as a validator is marked as weak or, when an HTTP-date
674   is used as the validator, if the date value is not strong in the sense
675   defined by &lastmod-comparison;. (A server can distinguish between a
676   valid HTTP-date and any form of entity-tag by examining the first
677   two characters.)
678</t>
679<t>
680   The If-Range header field &SHOULD; only be sent by clients together with
681   a Range header field.  The If-Range header field &MUST; be ignored if it
682   is received in a request that does not include a Range header field.
683   The If-Range header field &MUST; be ignored by a server that does not
684   support the sub-range operation.
685</t>
686<t>
687   If the validator given in the If-Range header field matches the current
688   validator for the selected representation of the target resource, then
689   the server &SHOULD; send the specified sub-range of the representation
690   using a <x:ref>206 (Partial Content)</x:ref> response. If the validator does not match,
691   then the server &SHOULD; send the entire representation using a <x:ref>200 (OK)</x:ref>
692   response.
693</t>
694</section>
695
696<section title="Range" anchor="header.range">
697  <iref primary="true" item="Range header field" x:for-anchor=""/>
698  <iref primary="true" item="Header Fields" subitem="Range" x:for-anchor=""/>
699
700<section title="Byte Ranges" anchor="byte.ranges">
701<t>
702   Since all HTTP representations are transferred as sequences
703   of bytes, the concept of a byte range is meaningful for any HTTP
704   representation. (However, not all clients and servers need to support byte-range
705   operations.)
706</t>
707<t>
708   Byte range specifications in HTTP apply to the sequence of bytes in
709   the representation body (not necessarily the same as the message body).
710</t>
711<t anchor="rule.ranges-specifier">
712  <x:anchor-alias value="byte-range-set"/>
713  <x:anchor-alias value="byte-range-spec"/>
714  <x:anchor-alias value="byte-ranges-specifier"/>
715  <x:anchor-alias value="first-byte-pos"/>
716  <x:anchor-alias value="last-byte-pos"/>
717  <x:anchor-alias value="ranges-specifier"/>
718  <x:anchor-alias value="suffix-byte-range-spec"/>
719  <x:anchor-alias value="suffix-length"/>
720
721   A byte range operation &MAY; specify a single range of bytes, or a set
722   of ranges within a single representation.
723</t>
724<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"/>
725  <x:ref>byte-ranges-specifier</x:ref> = <x:ref>bytes-unit</x:ref> "=" <x:ref>byte-range-set</x:ref>
726  <x:ref>byte-range-set</x:ref>  = 1#( <x:ref>byte-range-spec</x:ref> / <x:ref>suffix-byte-range-spec</x:ref> )
727  <x:ref>byte-range-spec</x:ref> = <x:ref>first-byte-pos</x:ref> "-" [ <x:ref>last-byte-pos</x:ref> ]
728  <x:ref>first-byte-pos</x:ref>  = 1*<x:ref>DIGIT</x:ref>
729  <x:ref>last-byte-pos</x:ref>   = 1*<x:ref>DIGIT</x:ref>
730</artwork></figure>
731<t>
732   The first-byte-pos value in a byte-range-spec gives the byte-offset
733   of the first byte in a range. The last-byte-pos value gives the
734   byte-offset of the last byte in the range; that is, the byte
735   positions specified are inclusive. Byte offsets start at zero.
736</t>
737<t>
738   If the last-byte-pos value is present, it &MUST; be greater than or
739   equal to the first-byte-pos in that byte-range-spec, or the byte-range-spec
740   is syntactically invalid. The recipient of a byte-range-set
741   that includes one or more syntactically invalid byte-range-spec
742   values &MUST; ignore the header field that includes that byte-range-set.
743</t>
744<t>
745   If the last-byte-pos value is absent, or if the value is greater than
746   or equal to the current length of the representation body, last-byte-pos is
747   taken to be equal to one less than the current length of the representation
748   in bytes.
749</t>
750<t>
751   By its choice of last-byte-pos, a client can limit the number of
752   bytes retrieved without knowing the size of the representation.
753</t>
754<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="suffix-byte-range-spec"/><iref primary="true" item="Grammar" subitem="suffix-length"/>
755  <x:ref>suffix-byte-range-spec</x:ref> = "-" <x:ref>suffix-length</x:ref>
756  <x:ref>suffix-length</x:ref> = 1*<x:ref>DIGIT</x:ref>
757</artwork></figure>
758<t>
759   A suffix-byte-range-spec is used to specify the suffix of the
760   representation body, of a length given by the suffix-length value. (That is,
761   this form specifies the last N bytes of a representation.) If the
762   representation is shorter than the specified suffix-length, the entire
763   representation is used.
764</t>
765<t>
766   If a syntactically valid byte-range-set includes at least one byte-range-spec
767   whose first-byte-pos is less than the current length of
768   the representation, or at least one suffix-byte-range-spec with a non-zero
769   suffix-length, then the byte-range-set is satisfiable.
770   Otherwise, the byte-range-set is unsatisfiable. If the byte-range-set
771   is unsatisfiable, the server &SHOULD; return a response with a
772   <x:ref>416 (Requested Range Not Satisfiable)</x:ref> status code. Otherwise, the server
773   &SHOULD; return a response with a <x:ref>206 (Partial Content)</x:ref> status code
774   containing the satisfiable ranges of the representation.
775</t>
776<t>
777   Examples of byte-ranges-specifier values (assuming a representation of
778   length 10000):
779  <list style="symbols">
780     <t>The first 500 bytes (byte offsets 0-499, inclusive):
781<figure><artwork type="example" x:indent-with="   ">
782  bytes=0-499
783</artwork></figure>
784    </t>
785     <t>The second 500 bytes (byte offsets 500-999, inclusive):
786<figure><artwork type="example" x:indent-with="   ">
787  bytes=500-999
788</artwork></figure>
789    </t>
790     <t>The final 500 bytes (byte offsets 9500-9999, inclusive):
791<figure><artwork type="example" x:indent-with="   ">
792  bytes=-500
793</artwork></figure>
794    Or:
795<figure><artwork type="example" x:indent-with="   ">
796  bytes=9500-
797</artwork></figure>
798    </t>
799     <t>The first and last bytes only (bytes 0 and 9999):
800<figure><artwork type="example" x:indent-with="   ">
801  bytes=0-0,-1
802</artwork></figure>
803     </t>
804     <t>Several legal but not canonical specifications of the second 500
805        bytes (byte offsets 500-999, inclusive):
806<figure><artwork type="example" x:indent-with="   ">
807  bytes=500-600,601-999
808  bytes=500-700,601-999
809</artwork></figure>
810     </t>
811  </list>
812</t>
813</section>
814
815<section title="Range Retrieval Requests" anchor="range.retrieval.requests">
816  <x:anchor-alias value="Range"/>
817  <x:anchor-alias value="other-ranges-specifier"/>
818  <x:anchor-alias value="other-range-set"/>
819<t>
820   The "Range" header field defines the GET method (conditional or
821   not) to request one or more sub-ranges of the response representation body, instead
822   of the entire representation body.
823</t>
824<figure><artwork type="abnf2616"><iref primary="true" item="Grammar" subitem="Range"/>
825  <x:ref>Range</x:ref> = <x:ref>byte-ranges-specifier</x:ref> / <x:ref>other-ranges-specifier</x:ref>
826  <x:ref>other-ranges-specifier</x:ref> = <x:ref>other-range-unit</x:ref> "=" <x:ref>other-range-set</x:ref>
827  <x:ref>other-range-set</x:ref> = 1*<x:ref>CHAR</x:ref>
828</artwork></figure>
829<t>
830   A server &MAY; ignore the Range header field. However, origin
831   servers and intermediate caches ought to support byte ranges when
832   possible, since Range supports efficient recovery from partially
833   failed transfers, and supports efficient partial retrieval of large
834   representations.
835</t>
836<t>
837   If the server supports the Range header field and the specified range or
838   ranges are appropriate for the representation:
839  <list style="symbols">
840     <t>The presence of a Range header field in an unconditional GET modifies
841        what is returned if the GET is otherwise successful. In other
842        words, the response carries a status code of <x:ref>206 (Partial Content)</x:ref>
843        instead of <x:ref>200 (OK)</x:ref>.</t>
844
845     <t>The presence of a Range header field in a conditional GET (a request
846        using one or both of <x:ref>If-Modified-Since</x:ref> and
847        <x:ref>If-None-Match</x:ref>, or one or both of
848        <x:ref>If-Unmodified-Since</x:ref> and <x:ref>If-Match</x:ref>) modifies
849        what is returned if the GET is otherwise successful and the
850        condition is true. It does not affect the <x:ref>304 (Not Modified)</x:ref>
851        response returned if the conditional is false.</t>
852  </list>
853</t>
854<t>
855   In some cases, it might be more appropriate to use the If-Range
856   header field (see <xref target="header.if-range"/>) in addition to the Range
857   header field.
858</t>
859<t>
860   If a proxy that supports ranges receives a Range request, forwards
861   the request to an inbound server, and receives an entire representation in
862   reply, it &MAY; only return the requested range to its client.
863</t>
864</section>
865</section>
866</section>
867
868<section title="IANA Considerations" anchor="IANA.considerations">
869
870<section title="Status Code Registration" anchor="status.code.registration">
871<t>
872   The HTTP Status Code Registry located at <eref target="http://www.iana.org/assignments/http-status-codes"/>
873   shall be updated with the registrations below:
874</t>
875<?BEGININC p5-range.iana-status-codes ?>
876<!--AUTOGENERATED FROM extract-status-code-defs.xslt, do not edit manually-->
877<texttable align="left" suppress-title="true" anchor="iana.status.code.registration.table">
878   <ttcol>Value</ttcol>
879   <ttcol>Description</ttcol>
880   <ttcol>Reference</ttcol>
881   <c>206</c>
882   <c>Partial Content</c>
883   <c>
884      <xref target="status.206"/>
885   </c>
886   <c>416</c>
887   <c>Requested Range Not Satisfiable</c>
888   <c>
889      <xref target="status.416"/>
890   </c>
891</texttable>
892<!--(END)-->
893<?ENDINC p5-range.iana-status-codes ?>
894</section>
895
896<section title="Header Field Registration" anchor="header.field.registration">
897<t>
898   The Message Header Field Registry located at <eref target="http://www.iana.org/assignments/message-headers/message-header-index.html"/> shall be updated
899   with the permanent registrations below (see <xref target="RFC3864"/>):
900</t>
901<?BEGININC p5-range.iana-headers ?>
902<!--AUTOGENERATED FROM extract-header-defs.xslt, do not edit manually-->
903<texttable align="left" suppress-title="true" anchor="iana.header.registration.table">
904   <ttcol>Header Field Name</ttcol>
905   <ttcol>Protocol</ttcol>
906   <ttcol>Status</ttcol>
907   <ttcol>Reference</ttcol>
908
909   <c>Accept-Ranges</c>
910   <c>http</c>
911   <c>standard</c>
912   <c>
913      <xref target="header.accept-ranges"/>
914   </c>
915   <c>Content-Range</c>
916   <c>http</c>
917   <c>standard</c>
918   <c>
919      <xref target="header.content-range"/>
920   </c>
921   <c>If-Range</c>
922   <c>http</c>
923   <c>standard</c>
924   <c>
925      <xref target="header.if-range"/>
926   </c>
927   <c>Range</c>
928   <c>http</c>
929   <c>standard</c>
930   <c>
931      <xref target="header.range"/>
932   </c>
933</texttable>
934<!--(END)-->
935<?ENDINC p5-range.iana-headers ?>
936<t>
937   The change controller is: "IETF (iesg@ietf.org) - Internet Engineering Task Force".
938</t>
939</section>
940
941<section title="Range Specifier Registration" anchor="range.specifier.registration">
942<t>
943  The registration procedure for HTTP Range Specifiers is defined by
944  <xref target="range.specifier.registry"/> of this document.
945</t>
946<t>
947   The HTTP Range Specifier Registry shall be created at <eref target="http://www.iana.org/assignments/http-range-specifiers"/>
948   and be populated with the registrations below:
949</t>
950<texttable align="left" suppress-title="true" anchor="iana.range.specifiers.table">
951   <ttcol>Range Specifier Name</ttcol>
952   <ttcol>Description</ttcol>
953   <ttcol>Reference</ttcol>
954
955   <c>bytes</c>
956   <c>a range of octets</c>
957   <c>(this specification)</c>
958</texttable>
959<t>
960   The change controller is: "IETF (iesg@ietf.org) - Internet Engineering Task Force".
961</t>
962</section>
963</section>
964
965<section title="Security Considerations" anchor="security.considerations">
966<t>
967   This section is meant to inform application developers, information
968   providers, and users of the security limitations in HTTP/1.1 as
969   described by this document. The discussion does not include
970   definitive solutions to the problems revealed, though it does make
971   some suggestions for reducing security risks.
972</t>
973<section title="Overlapping Ranges" anchor="overlapping.ranges">
974<t>
975   Range requests containing overlapping ranges can lead to the situation
976   where a server is sending far more data than the size of the complete
977   resource representation.
978</t>
979</section>
980</section>
981
982<section title="Acknowledgments" anchor="acks">
983<t>
984  See &acks;.
985</t>
986</section>
987</middle>
988<back>
989
990<references title="Normative References">
991
992<reference anchor="Part1">
993  <front>
994    <title>HTTP/1.1, part 1: URIs, Connections, and Message Parsing</title>
995    <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
996      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
997      <address><email>fielding@gbiv.com</email></address>
998    </author>
999    <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
1000      <organization abbrev="W3C">World Wide Web Consortium</organization>
1001      <address><email>ylafon@w3.org</email></address>
1002    </author>
1003    <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
1004      <organization abbrev="greenbytes">greenbytes GmbH</organization>
1005      <address><email>julian.reschke@greenbytes.de</email></address>
1006    </author>
1007    <date month="&ID-MONTH;" year="&ID-YEAR;"/>
1008  </front>
1009  <seriesInfo name="Internet-Draft" value="draft-ietf-httpbis-p1-messaging-&ID-VERSION;"/>
1010  <x:source href="p1-messaging.xml" basename="p1-messaging"/>
1011</reference>
1012
1013<reference anchor="Part2">
1014  <front>
1015    <title>HTTP/1.1, part 2: Message Semantics, Payload and Content Negotiation</title>
1016    <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
1017      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1018      <address><email>fielding@gbiv.com</email></address>
1019    </author>
1020    <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
1021      <organization abbrev="W3C">World Wide Web Consortium</organization>
1022      <address><email>ylafon@w3.org</email></address>
1023    </author>
1024    <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
1025      <organization abbrev="greenbytes">greenbytes GmbH</organization>
1026      <address><email>julian.reschke@greenbytes.de</email></address>
1027    </author>
1028    <date month="&ID-MONTH;" year="&ID-YEAR;"/>
1029  </front>
1030  <seriesInfo name="Internet-Draft" value="draft-ietf-httpbis-p2-semantics-&ID-VERSION;"/>
1031  <x:source href="p2-semantics.xml" basename="p2-semantics">
1032    <x:defines>200 (OK)</x:defines>
1033    <x:defines>410 (Gone)</x:defines>
1034  </x:source>
1035</reference>
1036
1037<reference anchor="Part4">
1038  <front>
1039    <title>HTTP/1.1, part 4: Conditional Requests</title>
1040    <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
1041      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1042      <address><email>fielding@gbiv.com</email></address>
1043    </author>
1044    <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
1045      <organization abbrev="W3C">World Wide Web Consortium</organization>
1046      <address><email>ylafon@w3.org</email></address>
1047    </author>
1048    <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
1049      <organization abbrev="greenbytes">greenbytes GmbH</organization>
1050      <address><email>julian.reschke@greenbytes.de</email></address>
1051    </author>
1052    <date month="&ID-MONTH;" year="&ID-YEAR;"/>
1053  </front>
1054  <seriesInfo name="Internet-Draft" value="draft-ietf-httpbis-p4-conditional-&ID-VERSION;"/>
1055  <x:source href="p4-conditional.xml" basename="p4-conditional">
1056    <x:defines>304 (Not Modified)</x:defines>
1057    <x:defines>ETag</x:defines>
1058    <x:defines>If-Match</x:defines>
1059    <x:defines>If-Modified-Since</x:defines>
1060    <x:defines>If-None-Match</x:defines>
1061    <x:defines>If-Unmodified-Since</x:defines>
1062    <x:defines>Last-Modified</x:defines>
1063  </x:source>
1064</reference>
1065
1066<reference anchor="Part6">
1067  <front>
1068    <title>HTTP/1.1, part 6: Caching</title>
1069    <author initials="R." surname="Fielding" fullname="Roy T. Fielding" role="editor">
1070      <organization abbrev="Adobe">Adobe Systems Incorporated</organization>
1071      <address><email>fielding@gbiv.com</email></address>
1072    </author>
1073    <author initials="Y." surname="Lafon" fullname="Yves Lafon" role="editor">
1074      <organization abbrev="W3C">World Wide Web Consortium</organization>
1075      <address><email>ylafon@w3.org</email></address>
1076    </author>
1077    <author initials="M." surname="Nottingham" fullname="Mark Nottingham" role="editor">
1078      <organization>Rackspace</organization>
1079      <address><email>mnot@mnot.net</email></address>
1080    </author>
1081    <author initials="J. F." surname="Reschke" fullname="Julian F. Reschke" role="editor">
1082      <organization abbrev="greenbytes">greenbytes GmbH</organization>
1083      <address><email>julian.reschke@greenbytes.de</email></address>
1084    </author>
1085    <date month="&ID-MONTH;" year="&ID-YEAR;"/>
1086  </front>
1087  <seriesInfo name="Internet-Draft" value="draft-ietf-httpbis-p6-cache-&ID-VERSION;"/>
1088  <x:source href="p6-cache.xml" basename="p6-cache">
1089    <x:defines>Cache-Control</x:defines>
1090    <x:defines>Expires</x:defines>
1091    <x:defines>Vary</x:defines>
1092  </x:source>
1093</reference>
1094
1095<reference anchor="RFC2046">
1096  <front>
1097    <title abbrev="Media Types">Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types</title>
1098    <author initials="N." surname="Freed" fullname="Ned Freed">
1099      <organization>Innosoft International, Inc.</organization>
1100      <address><email>ned@innosoft.com</email></address>
1101    </author>
1102    <author initials="N." surname="Borenstein" fullname="Nathaniel S. Borenstein">
1103      <organization>First Virtual Holdings</organization>
1104      <address><email>nsb@nsb.fv.com</email></address>
1105    </author>
1106    <date month="November" year="1996"/>
1107  </front>
1108  <seriesInfo name="RFC" value="2046"/>
1109</reference>
1110
1111<reference anchor="RFC2119">
1112  <front>
1113    <title>Key words for use in RFCs to Indicate Requirement Levels</title>
1114    <author initials="S." surname="Bradner" fullname="Scott Bradner">
1115      <organization>Harvard University</organization>
1116      <address><email>sob@harvard.edu</email></address>
1117    </author>
1118    <date month="March" year="1997"/>
1119  </front>
1120  <seriesInfo name="BCP" value="14"/>
1121  <seriesInfo name="RFC" value="2119"/>
1122</reference>
1123
1124<reference anchor="RFC5234">
1125  <front>
1126    <title abbrev="ABNF for Syntax Specifications">Augmented BNF for Syntax Specifications: ABNF</title>
1127    <author initials="D." surname="Crocker" fullname="Dave Crocker" role="editor">
1128      <organization>Brandenburg InternetWorking</organization>
1129      <address>
1130        <email>dcrocker@bbiw.net</email>
1131      </address> 
1132    </author>
1133    <author initials="P." surname="Overell" fullname="Paul Overell">
1134      <organization>THUS plc.</organization>
1135      <address>
1136        <email>paul.overell@thus.net</email>
1137      </address>
1138    </author>
1139    <date month="January" year="2008"/>
1140  </front>
1141  <seriesInfo name="STD" value="68"/>
1142  <seriesInfo name="RFC" value="5234"/>
1143</reference>
1144
1145</references>
1146
1147<references title="Informative References">
1148
1149<reference anchor="RFC2616">
1150  <front>
1151    <title>Hypertext Transfer Protocol -- HTTP/1.1</title>
1152    <author initials="R." surname="Fielding" fullname="R. Fielding">
1153      <organization>University of California, Irvine</organization>
1154      <address><email>fielding@ics.uci.edu</email></address>
1155    </author>
1156    <author initials="J." surname="Gettys" fullname="J. Gettys">
1157      <organization>W3C</organization>
1158      <address><email>jg@w3.org</email></address>
1159    </author>
1160    <author initials="J." surname="Mogul" fullname="J. Mogul">
1161      <organization>Compaq Computer Corporation</organization>
1162      <address><email>mogul@wrl.dec.com</email></address>
1163    </author>
1164    <author initials="H." surname="Frystyk" fullname="H. Frystyk">
1165      <organization>MIT Laboratory for Computer Science</organization>
1166      <address><email>frystyk@w3.org</email></address>
1167    </author>
1168    <author initials="L." surname="Masinter" fullname="L. Masinter">
1169      <organization>Xerox Corporation</organization>
1170      <address><email>masinter@parc.xerox.com</email></address>
1171    </author>
1172    <author initials="P." surname="Leach" fullname="P. Leach">
1173      <organization>Microsoft Corporation</organization>
1174      <address><email>paulle@microsoft.com</email></address>
1175    </author>
1176    <author initials="T." surname="Berners-Lee" fullname="T. Berners-Lee">
1177      <organization>W3C</organization>
1178      <address><email>timbl@w3.org</email></address>
1179    </author>
1180    <date month="June" year="1999"/>
1181  </front>
1182  <seriesInfo name="RFC" value="2616"/>
1183</reference>
1184
1185<reference anchor='RFC3864'>
1186  <front>
1187    <title>Registration Procedures for Message Header Fields</title>
1188    <author initials='G.' surname='Klyne' fullname='G. Klyne'>
1189      <organization>Nine by Nine</organization>
1190      <address><email>GK-IETF@ninebynine.org</email></address>
1191    </author>
1192    <author initials='M.' surname='Nottingham' fullname='M. Nottingham'>
1193      <organization>BEA Systems</organization>
1194      <address><email>mnot@pobox.com</email></address>
1195    </author>
1196    <author initials='J.' surname='Mogul' fullname='J. Mogul'>
1197      <organization>HP Labs</organization>
1198      <address><email>JeffMogul@acm.org</email></address>
1199    </author>
1200    <date year='2004' month='September' />
1201  </front>
1202  <seriesInfo name='BCP' value='90' />
1203  <seriesInfo name='RFC' value='3864' />
1204</reference>
1205
1206<reference anchor="RFC4288">
1207  <front>
1208    <title>Media Type Specifications and Registration Procedures</title>
1209    <author initials="N." surname="Freed" fullname="N. Freed">
1210      <organization>Sun Microsystems</organization>
1211      <address>
1212        <email>ned.freed@mrochek.com</email>
1213      </address>
1214    </author>
1215    <author initials="J." surname="Klensin" fullname="J. Klensin">
1216      <address>
1217        <email>klensin+ietf@jck.com</email>
1218      </address>
1219    </author>
1220    <date year="2005" month="December"/>
1221  </front>
1222  <seriesInfo name="BCP" value="13"/>
1223  <seriesInfo name="RFC" value="4288"/>
1224</reference>
1225
1226<reference anchor='RFC5226'>
1227  <front>
1228    <title>Guidelines for Writing an IANA Considerations Section in RFCs</title>
1229    <author initials='T.' surname='Narten' fullname='T. Narten'>
1230      <organization>IBM</organization>
1231      <address><email>narten@us.ibm.com</email></address>
1232    </author>
1233    <author initials='H.' surname='Alvestrand' fullname='H. Alvestrand'>
1234      <organization>Google</organization>
1235      <address><email>Harald@Alvestrand.no</email></address>
1236    </author>
1237    <date year='2008' month='May' />
1238  </front>
1239  <seriesInfo name='BCP' value='26' />
1240  <seriesInfo name='RFC' value='5226' />
1241</reference>
1242
1243</references>
1244
1245<section title="Internet Media Type multipart/byteranges" anchor="internet.media.type.multipart.byteranges">
1246<iref item="Media Type" subitem="multipart/byteranges" primary="true"/>
1247<iref item="multipart/byteranges Media Type" primary="true"/>
1248<t>
1249   When an HTTP <x:ref>206 (Partial Content)</x:ref> response message includes the
1250   content of multiple ranges (a response to a request for multiple
1251   non-overlapping ranges), these are transmitted as a multipart
1252   message body (<xref target="RFC2046" x:fmt="," x:sec="5.1"/>). The media type for this purpose is called
1253   "multipart/byteranges".  The following is to be registered with IANA <xref target="RFC4288"/>.
1254</t>
1255<x:note>
1256  <t>
1257    &Note; Despite the name "multipart/byteranges" is not limited to the byte ranges only.
1258  </t>
1259</x:note>
1260<t>
1261   The multipart/byteranges media type includes one or more parts, each
1262   with its own Content-Type and <x:ref>Content-Range</x:ref> fields. The
1263   required boundary parameter specifies the boundary string used to separate
1264   each body-part.
1265</t>
1266<t>
1267  <list style="hanging" x:indent="12em">
1268    <t hangText="Type name:">
1269      multipart
1270    </t>
1271    <t hangText="Subtype name:">
1272      byteranges
1273    </t>
1274    <t hangText="Required parameters:">
1275      boundary
1276    </t>
1277    <t hangText="Optional parameters:">
1278      none
1279    </t>
1280    <t hangText="Encoding considerations:">
1281      only "7bit", "8bit", or "binary" are permitted
1282    </t>
1283    <t hangText="Security considerations:">
1284      none
1285    </t>
1286    <t hangText="Interoperability considerations:">
1287      none
1288    </t>
1289    <t hangText="Published specification:">
1290      This specification (see <xref target="internet.media.type.multipart.byteranges"/>).
1291    </t>
1292    <t hangText="Applications that use this media type:">
1293    </t>
1294    <t hangText="Additional information:">
1295      <list style="hanging">
1296        <t hangText="Magic number(s):">none</t>
1297        <t hangText="File extension(s):">none</t>
1298        <t hangText="Macintosh file type code(s):">none</t>
1299      </list>
1300    </t>
1301    <t hangText="Person and email address to contact for further information:">
1302      See Authors Section.
1303    </t>
1304    <t hangText="Intended usage:">
1305      COMMON
1306    </t>
1307    <t hangText="Restrictions on usage:">
1308      none
1309    </t>
1310    <t hangText="Author/Change controller:">
1311      IESG
1312    </t>
1313  </list>
1314</t>
1315<figure><preamble>
1316   For example:
1317</preamble><artwork type="example">
1318  HTTP/1.1 206 Partial Content
1319  Date: Wed, 15 Nov 1995 06:25:24 GMT
1320  Last-Modified: Wed, 15 Nov 1995 04:58:08 GMT
1321  Content-type: multipart/byteranges; boundary=THIS_STRING_SEPARATES
1322 
1323  --THIS_STRING_SEPARATES
1324  Content-type: application/pdf
1325  Content-range: bytes 500-999/8000
1326 
1327  ...the first range...
1328  --THIS_STRING_SEPARATES
1329  Content-type: application/pdf
1330  Content-range: bytes 7000-7999/8000
1331 
1332  ...the second range
1333  --THIS_STRING_SEPARATES--
1334</artwork></figure>
1335<figure><preamble>
1336   Other example:
1337</preamble>
1338<artwork type="example">
1339  HTTP/1.1 206 Partial Content
1340  Date: Tue, 14 Nov 1995 06:25:24 GMT
1341  Last-Modified: Tue, 14 July 04:58:08 GMT
1342  Content-type: multipart/byteranges; boundary=THIS_STRING_SEPARATES
1343 
1344  --THIS_STRING_SEPARATES
1345  Content-type: video/example
1346  Content-range: exampleunit 1.2-4.3/25
1347 
1348  ...the first range...
1349  --THIS_STRING_SEPARATES
1350  Content-type: video/example
1351  Content-range: exampleunit 11.2-14.3/25
1352 
1353  ...the second range
1354  --THIS_STRING_SEPARATES--
1355</artwork>
1356</figure>
1357<t>
1358      Notes:
1359  <list style="numbers">
1360      <t>Additional CRLFs &MAY; precede the first boundary string in the body.</t>
1361
1362      <t>Although <xref target="RFC2046"/> permits the boundary string to be
1363         quoted, some existing implementations handle a quoted boundary
1364         string incorrectly.</t>
1365
1366      <t>A number of clients and servers were coded to an early draft
1367         of the byteranges specification to use a media type of
1368         multipart/x-byteranges<iref item="multipart/x-byteranges Media Type"/><iref item="Media Type" subitem="multipart/x-byteranges"/>, which is almost, but not quite
1369         compatible with the version documented in HTTP/1.1.</t>
1370  </list>
1371</t>
1372</section>
1373
1374<section title="Changes from RFC 2616" anchor="changes.from.rfc.2616">
1375<t>
1376  Clarify that it is not ok to use a weak validator in a <x:ref>206</x:ref> response.
1377  (<xref target="status.206"/>)
1378</t>
1379<t>
1380  Change ABNF productions for header fields to only define the field value.
1381  (<xref target="header.field.definitions"/>)
1382</t>
1383<t>
1384  Clarify that multipart/byteranges can consist of a single part.
1385  (<xref target="internet.media.type.multipart.byteranges"/>)
1386</t>
1387</section>
1388
1389<?BEGININC p5-range.abnf-appendix ?>
1390<section xmlns:x="http://purl.org/net/xml2rfc/ext" title="Collected ABNF" anchor="collected.abnf">
1391<figure>
1392<artwork type="abnf" name="p5-range.parsed-abnf">
1393<x:ref>Accept-Ranges</x:ref> = acceptable-ranges
1394
1395<x:ref>Content-Range</x:ref> = byte-content-range-spec / other-content-range-spec
1396
1397<x:ref>HTTP-date</x:ref> = &lt;HTTP-date, defined in [Part2], Section 5.1&gt;
1398
1399<x:ref>If-Range</x:ref> = entity-tag / HTTP-date
1400
1401<x:ref>OWS</x:ref> = &lt;OWS, defined in [Part1], Section 3.2.1&gt;
1402
1403<x:ref>Range</x:ref> = byte-ranges-specifier / other-ranges-specifier
1404
1405<x:ref>acceptable-ranges</x:ref> = ( *( "," OWS ) range-unit *( OWS "," [ OWS
1406 range-unit ] ) ) / "none"
1407
1408<x:ref>byte-content-range-spec</x:ref> = bytes-unit SP byte-range-resp-spec "/" (
1409 instance-length / "*" )
1410<x:ref>byte-range-resp-spec</x:ref> = ( first-byte-pos "-" last-byte-pos ) / "*"
1411<x:ref>byte-range-set</x:ref> = *( "," OWS ) ( byte-range-spec /
1412 suffix-byte-range-spec ) *( OWS "," [ OWS ( byte-range-spec /
1413 suffix-byte-range-spec ) ] )
1414<x:ref>byte-range-spec</x:ref> = first-byte-pos "-" [ last-byte-pos ]
1415<x:ref>byte-ranges-specifier</x:ref> = bytes-unit "=" byte-range-set
1416<x:ref>bytes-unit</x:ref> = "bytes"
1417
1418<x:ref>entity-tag</x:ref> = &lt;entity-tag, defined in [Part4], Section 2.3&gt;
1419
1420<x:ref>first-byte-pos</x:ref> = 1*DIGIT
1421
1422<x:ref>instance-length</x:ref> = 1*DIGIT
1423
1424<x:ref>last-byte-pos</x:ref> = 1*DIGIT
1425
1426<x:ref>other-content-range-spec</x:ref> = other-range-unit SP other-range-resp-spec
1427<x:ref>other-range-resp-spec</x:ref> = *CHAR
1428<x:ref>other-range-set</x:ref> = 1*CHAR
1429<x:ref>other-range-unit</x:ref> = token
1430<x:ref>other-ranges-specifier</x:ref> = other-range-unit "=" other-range-set
1431
1432<x:ref>range-unit</x:ref> = bytes-unit / other-range-unit
1433
1434<x:ref>suffix-byte-range-spec</x:ref> = "-" suffix-length
1435<x:ref>suffix-length</x:ref> = 1*DIGIT
1436
1437<x:ref>token</x:ref> = &lt;token, defined in [Part1], Section 3.2.4&gt;
1438</artwork>
1439</figure>
1440<figure><preamble>ABNF diagnostics:</preamble><artwork type="inline">
1441; Accept-Ranges defined but not used
1442; Content-Range defined but not used
1443; If-Range defined but not used
1444; Range defined but not used
1445</artwork></figure></section>
1446<?ENDINC p5-range.abnf-appendix ?>
1447
1448
1449<section title="Change Log (to be removed by RFC Editor before publication)" anchor="change.log">
1450
1451<section title="Since RFC 2616">
1452<t>
1453  Extracted relevant partitions from <xref target="RFC2616"/>.
1454</t>
1455</section>
1456
1457<section title="Since draft-ietf-httpbis-p5-range-00">
1458<t>
1459  Closed issues:
1460  <list style="symbols"> 
1461    <t>
1462      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/18"/>:
1463      "Cache validators in 206 responses"
1464      (<eref target="http://purl.org/NET/http-errata#ifrange206"/>)
1465    </t>
1466    <t>
1467      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/35"/>:
1468      "Normative and Informative references"
1469    </t>
1470    <t>
1471      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/86"/>:
1472      "Normative up-to-date references"
1473    </t>
1474  </list>
1475</t>
1476</section>
1477
1478<section title="Since draft-ietf-httpbis-p5-range-01">
1479<t>
1480  Closed issues:
1481  <list style="symbols"> 
1482    <t>
1483      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/55"/>:
1484      "Updating to RFC4288"
1485    </t>
1486  </list>
1487</t>
1488<t>
1489  Ongoing work on ABNF conversion (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/36"/>):
1490  <list style="symbols"> 
1491    <t>
1492      Add explicit references to BNF syntax and rules imported from other parts of the specification.
1493    </t>
1494  </list>
1495</t>
1496</section>
1497
1498<section title="Since draft-ietf-httpbis-p5-range-02" anchor="changes.since.02">
1499<t>
1500  Ongoing work on IANA Message Header Field Registration (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/40"/>):
1501  <list style="symbols"> 
1502    <t>
1503      Reference RFC 3984, and update header field registrations for headers defined
1504      in this document.
1505    </t>
1506  </list>
1507</t>
1508</section>
1509
1510<section title="Since draft-ietf-httpbis-p5-range-03" anchor="changes.since.03">
1511<t>
1512  None.
1513</t>
1514</section>
1515
1516<section title="Since draft-ietf-httpbis-p5-range-04" anchor="changes.since.04">
1517<t>
1518  Closed issues:
1519  <list style="symbols"> 
1520    <t>
1521      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/133"/>:
1522      "multipart/byteranges minimum number of parts"
1523    </t>
1524  </list>
1525</t>
1526<t>
1527  Ongoing work on ABNF conversion (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/36"/>):
1528  <list style="symbols"> 
1529    <t>
1530      Use "/" instead of "|" for alternatives.
1531    </t>
1532    <t>
1533      Introduce new ABNF rules for "bad" whitespace ("BWS"), optional
1534      whitespace ("OWS") and required whitespace ("RWS").
1535    </t>
1536    <t>
1537      Rewrite ABNFs to spell out whitespace rules, factor out
1538      header field value format definitions.
1539    </t>
1540  </list>
1541</t>
1542</section>
1543
1544<section title="Since draft-ietf-httpbis-p5-range-05" anchor="changes.since.05">
1545<t>
1546  Closed issues:
1547  <list style="symbols"> 
1548    <t>
1549      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/142"/>:
1550      "State base for *-byte-pos and suffix-length"
1551    </t>
1552  </list>
1553</t>
1554<t>
1555  Ongoing work on Custom Ranges (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/85"/>):
1556  <list style="symbols"> 
1557    <t>
1558      Remove bias in favor of byte ranges; allow custom ranges in ABNF.
1559    </t>
1560  </list>
1561</t>
1562<t>
1563  Final work on ABNF conversion (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/36"/>):
1564  <list style="symbols"> 
1565    <t>
1566      Add appendix containing collected and expanded ABNF, reorganize ABNF introduction.
1567    </t>
1568  </list>
1569</t>
1570</section>
1571
1572<section title="Since draft-ietf-httpbis-p5-range-06" anchor="changes.since.06">
1573<t>
1574  Closed issues:
1575  <list style="symbols"> 
1576    <t>
1577      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/161"/>:
1578      "base for numeric protocol elements"
1579    </t>
1580  </list>
1581</t>
1582</section>
1583
1584<section title="Since draft-ietf-httpbis-p5-range-07" anchor="changes.since.07">
1585<t>
1586  Closed issues:
1587  <list style="symbols">
1588    <t>
1589      Fixed discrepancy in the If-Range definition about allowed validators.
1590    </t>
1591    <t>
1592      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/150" />: "multipart/byteranges for custom range units"
1593    </t>
1594    <t>
1595      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/151" />: "range unit missing from other-ranges-specifier in Range header"
1596    </t>
1597    <t>
1598      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/198"/>:
1599      "move IANA registrations for optional status codes"
1600    </t>
1601  </list>
1602</t>
1603</section>
1604
1605<section title="Since draft-ietf-httpbis-p5-range-08" anchor="changes.since.08">
1606<t>
1607  No significant changes.
1608</t>
1609</section>
1610
1611<section title="Since draft-ietf-httpbis-p5-range-09" anchor="changes.since.09">
1612<t>
1613 No significant changes.
1614</t>
1615</section>
1616
1617<section title="Since draft-ietf-httpbis-p5-range-10" anchor="changes.since.10">
1618<t>
1619  Closed issues:
1620  <list style="symbols"> 
1621    <t>
1622      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/69"/>:
1623      "Clarify 'Requested Variant'"
1624    </t>
1625    <t>
1626      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/109"/>:
1627      "Clarify entity / representation / variant terminology"
1628    </t>
1629    <t>
1630      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/220"/>:
1631      "consider removing the 'changes from 2068' sections"
1632    </t>
1633  </list>
1634</t>
1635<t>
1636  Ongoing work on Custom Ranges (<eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/85"/>):
1637  <list style="symbols"> 
1638    <t>
1639      Add IANA registry.
1640    </t>
1641  </list>
1642</t>
1643</section>
1644
1645<section title="Since draft-ietf-httpbis-p5-range-11" anchor="changes.since.11">
1646<t>
1647  Closed issues:
1648  <list style="symbols"> 
1649    <t>
1650      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/217"/>:
1651      "Caches can't be required to serve ranges"
1652    </t>
1653  </list>
1654</t>
1655</section>
1656
1657<section title="Since draft-ietf-httpbis-p5-range-12" anchor="changes.since.12">
1658<t>
1659  Closed issues:
1660  <list style="symbols"> 
1661    <t>
1662      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/224"/>:
1663      "Header Classification"
1664    </t>
1665  </list>
1666</t>
1667</section>
1668
1669<section title="Since draft-ietf-httpbis-p5-range-13" anchor="changes.since.13">
1670<t>
1671  Closed issues:
1672  <list style="symbols">
1673    <t>
1674      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/276"/>:
1675      "untangle ABNFs for header fields"
1676    </t>
1677  </list>
1678</t>
1679</section>
1680
1681<section title="Since draft-ietf-httpbis-p5-range-14" anchor="changes.since.14">
1682<t>
1683  None.
1684</t>
1685</section>
1686
1687<section title="Since draft-ietf-httpbis-p5-range-15" anchor="changes.since.15">
1688<t>
1689  Closed issues:
1690  <list style="symbols">
1691    <t>
1692      <eref target="http://trac.tools.ietf.org/wg/httpbis/trac/ticket/175"/>:
1693      "Security consideration: range flooding"
1694    </t>
1695  </list>
1696</t>
1697</section>
1698
1699<section title="Since draft-ietf-httpbis-p5-range-16" anchor="changes.since.16">
1700<t>
1701  Closed issues:
1702  <list style="symbols"> 
1703    <t>
1704      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/186"/>:
1705      "Document HTTP's error-handling philosophy"
1706    </t>
1707    <t>
1708      <eref target="http://trac.tools.ietf.org/wg/httpbis/trac/ticket/301"/>:
1709      "Content-Range on responses other than 206"
1710    </t>
1711    <t>
1712      <eref target="http://trac.tools.ietf.org/wg/httpbis/trac/ticket/319"/>:
1713      "case sensitivity of ranges in p5"
1714    </t>
1715  </list>
1716</t>
1717</section>
1718
1719<section title="Since draft-ietf-httpbis-p5-range-17" anchor="changes.since.17">
1720<t>
1721  None.
1722</t>
1723</section>
1724
1725<section title="Since draft-ietf-httpbis-p5-range-18" anchor="changes.since.18">
1726<t>
1727  Closed issues:
1728  <list style="symbols"> 
1729    <t>
1730      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/311"/>:
1731      "Add limitations to Range to reduce its use as a denial-of-service tool"
1732    </t>
1733  </list>
1734</t>
1735</section>
1736
1737<section title="Since draft-ietf-httpbis-p5-range-19" anchor="changes.since.19">
1738<t>
1739  Closed issues:
1740  <list style="symbols"> 
1741    <t>
1742      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/358"/>:
1743      "ABNF list expansion code problem"
1744    </t>
1745    <t>
1746      <eref target="http://tools.ietf.org/wg/httpbis/trac/ticket/361"/>:
1747      "ABNF requirements for recipients"
1748    </t>
1749  </list>
1750</t>
1751</section>
1752
1753</section>
1754
1755</back>
1756</rfc>
Note: See TracBrowser for help on using the repository browser.