W3C home > Mailing lists > Public > ietf-http-wg-old@w3.org > May to August 1997

RANGES (Might be nice to allow 206 response to range request without knowing total content length)

From: Henrik Frystyk Nielsen <frystyk@w3.org>
Date: Mon, 12 May 1997 11:20:37 -0400
Message-Id: <3.0.1.32.19970512112037.00b93c00@pop.w3.org>
To: http-wg@cuckoo.hpl.hp.com

Summary of discussion:

There are situations where a server (especially a proxy) does not know the
full length of a response but is capable of serving a byterange request. We
therefore need a mechanism to allow byteranges with a content-range not
indicating the full length of the message.

Suggested Solution:

<<<<<

The Content-Range entity-header is sent with a partial entity-body to
specify where in the full entity-body the partial body should be inserted.
It also indicates the total size of the full entity-body. When a server
returns a partial response to a client, it must describe both the extent of
the range covered by the response, and the length of the entire entity-body. 

       Content-Range = "Content-Range" ":" content-range-spec
       content-range-spec      = byte-content-range-spec
       byte-content-range-spec = bytes-unit SP first-byte-pos "-"
                                 last-byte-pos "/" entity-length
       entity-length           = 1*DIGIT

=====

The Content-Range entity-header is sent with a partial entity-body to
specify where in the full entity-body the partial body should be inserted.
It SHOULD indicate the total length of the full entity-body, unless length
this is unknown or difficult to determine.

       Content-Range = "Content-Range" ":" content-range-spec
       content-range-spec      = byte-content-range-spec
       byte-content-range-spec = bytes-unit SP first-byte-pos "-"
                                 last-byte-pos "/" 
                                 ( entity-length | "*" )
       entity-length           = 1*DIGIT

The asterisk "*" character means that the the entity-length is unknown at
the time when the response was generated.

>>>>>

Thanks,

Henrik (and Jeff Mogul)

--
Henrik Frystyk Nielsen, <frystyk@w3.org>
World Wide Web Consortium
http://www.w3.org/People/Frystyk
Received on Monday, 12 May 1997 08:21:59 EDT

This archive was generated by hypermail pre-2.1.9 : Wednesday, 24 September 2003 06:32:41 EDT