Network Working Group R. Fielding Request for Comments: 2616 ...

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Note: while the definition of Content-MD5 is exactly the same forHTTP as in RFC 1864 for MIME entity-bodies, there are several waysin which the application of Content-MD5 to HTTP entity-bodiesdiffers from its application to MIME entity-bodies. One is thatHTTP, unlike MIME, does not use Content-Transfer-Encoding, anddoes use Transfer-Encoding and Content-Encoding. Another is thatHTTP more frequently uses binary content types than MIME, so it isworth noting that, in such cases, the byte order used to computethe digest is the transmission byte order defined for the type.Lastly, HTTP allows transmission of text types with any of severalline break conventions and not just the canonical form using CRLF.14.16 Content-RangeThe Content-Range entity-header is sent with a partial entity-body tospecify where in the full entity-body the partial body should beapplied. Range units are defined in section 3.12.Content-Range = "Content-Range" ":" content-range-speccontent-range-spec = byte-content-range-specbyte-content-range-spec = bytes-unit SPbyte-range-resp-spec "/"( instance-length | "*" )byte-range-resp-spec = (first-byte-pos "-" last-byte-pos)| "*"instance-length = 1*DIGITThe header SHOULD indicate the total length of the full entity-body,unless this length is unknown or difficult to determine. The asterisk"*" character means that the instance-length is unknown at the timewhen the response was generated.Unlike byte-ranges-specifier values (see section 14.35.1), a byterange-resp-specMUST only specify one range, and MUST containabsolute byte positions for both the first and last byte of therange.A byte-content-range-spec with a byte-range-resp-spec whose lastbyte-posvalue is less than its first-byte-pos value, or whoseinstance-length value is less than or equal to its last-byte-posvalue, is invalid. The recipient of an invalid byte-content-rangespecMUST ignore it and any content transferred along with it.A server sending a response with status code 416 (Requested range notsatisfiable) SHOULD include a Content-Range field with a byte-rangeresp-specof "*". The instance-length specifies the current length of
Fielding, et al. Standards Track [Page 122]RFC 2616 HTTP/1.1 June 1999the selected resource. A response with status code 206 (PartialContent) MUST NOT include a Content-Range field with a byte-rangeresp-specof "*".Examples of byte-content-range-spec values, assuming that the entitycontains a total of 1234 bytes:. The first 500 bytes:bytes 0-499/1234. The second 500 bytes:bytes 500-999/1234. All except for the first 500 bytes:bytes 500-1233/1234. The last 500 bytes:bytes 734-1233/1234When an HTTP message includes the content of a single range (forexample, a response to a request for a single range, or to a requestfor a set of ranges that overlap without any holes), this content istransmitted with a Content-Range header, and a Content-Length headershowing the number of bytes actually transferred. For example,HTTP/1.1 206 Partial contentDate: Wed, 15 Nov 1995 06:25:24 GMTLast-Modified: Wed, 15 Nov 1995 04:58:08 GMTContent-Range: bytes 21010-47021/47022Content-Length: 26012Content-Type: image/gifWhen an HTTP message includes the content of multiple ranges (forexample, a response to a request for multiple non-overlappingranges), these are transmitted as a multipart message. The multipartmedia type used for this purpose is "multipart/byteranges" as definedin appendix 19.2. See appendix 19.6.3 for a compatibility issue.A response to a request for a single range MUST NOT be sent using themultipart/byteranges media type. A response to a request formultiple ranges, whose result is a single range, MAY be sent as amultipart/byteranges media type with one part. A client that cannotdecode a multipart/byteranges message MUST NOT ask for multiplebyte-ranges in a single request.When a client requests multiple byte-ranges in one request, the
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eferred to as "HTTP/1.1", and is an
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12.1 Server-driven Negotiation ....
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14.40 Trailer .....................
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1.2 RequirementsThe key words "MUST
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Fielding, et al. Standards Track [P
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equest chain ----------------------
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Elements separated by a bar ("|") a
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HTTP/1.1 header field values can be
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An application that sends a request
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3.2.3 URI ComparisonWhen comparing
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is not desirable and is discouraged
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CRLFchunk = chunk-size [ chunk-exte
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When in canonical form, media subty
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3.9 Quality ValuesHTTP content nego
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RFC 2616 HTTP/1.1 June 1999HTTP/1.1
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message-body = entity-body| Transfe
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in advance.Messages MUST NOT includ
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equested resource, and 501 (Not Imp
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names) MUST use the following rules
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values for the first digit:- 1xx: I
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how the transfer-length of a messag
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connection-token close.If either th
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idempotent (see section 9.1.2). Non
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compatibility with RFC 2068, a serv
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If at any point an error status is
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optional features implemented by th
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- Extending a database through an a
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intervention (or other means) on th
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10.1.2 101 Switching ProtocolsThe s
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esponse MAY include new or updated
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The response MUST include the follo
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If the client is sending data, a se
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If the response could be unacceptab
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10.4.15 414 Request-URI Too LongThe
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10.5.5 504 Gateway TimeoutThe serve
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Caching would be useless if it did
Page 84 and 85: Warning (but without removing any e
Page 86 and 87: If the user has overridden the basi
Page 88 and 89: in the past. This means that the re
Page 90 and 91: RFC 2616 HTTP/1.1 June 1999the time
Page 92 and 93: simple:response_is_fresh = (freshne
Page 94 and 95: match.In HTTP/1.1, a conditional re
Page 96 and 97: validators or strong validators. Cl
Page 98 and 99: - MAY send a weak entity tag instea
Page 100 and 101: Unless specifically constrained by
Page 102 and 103: Fielding, et al. Standards Track [P
Page 104 and 105: warn-code 1xx, which are deleted ev
Page 106 and 107: for the associated entity, its enti
Page 108 and 109: - DELETE- POSTIn order to prevent d
Page 110 and 111: The Accept request-header field can
Page 112 and 113: image/jpeg = 0.5text/html;level=2 =
Page 114 and 115: Note: If the request does not inclu
Page 116 and 117: Accept-Ranges: bytesbut are not req
Page 118 and 119: containing an Authorization field,
Page 120 and 121: - Restrictions on what may be store
Page 122 and 123: improve privacy in some cases, we c
Page 126 and 127: must-revalidateBecause a cache MAY
Page 128 and 129: understand.For example, consider a
Page 130 and 131: new coding is known to be acceptabl
Page 132 and 133: 14.14 Content-LocationThe Content-L
Page 136 and 137: server SHOULD return them in the or
Page 138 and 139: Some origin server implementations
Page 140 and 141: Expires = "Expires" ":" HTTP-dateAn
Page 142 and 143: A client MUST include a Host header
Page 144 and 145: een modified since the date given b
Page 146 and 147: RFC 2616 HTTP/1.1 June 1999If none
Page 148 and 149: 14.29 Last-ModifiedThe Last-Modifie
Page 150 and 151: MAY require that behavior be consis
Page 152 and 153: yte-ranges-specifier = bytes-unit "
Page 154 and 155: Content) instead of 200 (OK).- The
Page 156 and 157: The TE request-header field indicat
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Page 162 and 163: SHOULD NOT, by default, forward the
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Page 166 and 167: designers and implementors be parti
Page 168 and 169: strongly correlated to the membersh
Page 170 and 171: serious security considerations. Co
Page 172 and 173: The HTTP protocol has evolved consi
Page 174 and 175: Protocol -- HTTP/1.0", RFC 1945, Ma
Page 176 and 177: Implementation and Analysis", RFC 1
Page 178 and 179: University of California, IrvineIrv
Page 182 and 183: Notes:1) Additional CRLFs may prece
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full compliance with the MIME proto
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ead chunk-size and CRLF}read entity
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- understand any valid response in
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CREATE had a race that required an
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also needed to be a general header,
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Network Working Group R. Fielding Request for Comments: 2616 ...

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