Re: Byteranges with 206 partial content

On Mon, 13 Nov 1995, Roy T. Fielding wrote:

> > An additional feature is to say "give me a range if the document
> > hasn't changed, but if it has, send me the entire document".  Similar
> > to If-modified-since, but still quite different...  What would you
> > call such a header?
> If-Modified-Since   (for the current case)
> Unless              (for the generic case)

Unless could work, if it's implemented in the same spec as byte ranges. 
If-Modified-Since will not work, though, because it's already in use for 
something different. Namely, one of the points of using a header instead 
of a URL extension or new HTTP method is so that non-byte range serverss 
will ignore it and send a 200 response and the entire document. Using 
If-Modified-Since defeats this, since non-byte range servers will return 
a 304.

I think either as I said in a previous message, or as Lou Montulli said, 
putting it in with the Request-Range header, would be best, because the 
behavior with respect to byte ranges really is quite different than the 
behavior with respect to entire documnets, in that if it has changed, it 
should send a 200 and the entire document, as opposed to the normal case, 
where a 304 is sent with no content.

--/ Alexei Kosut <> /--------/ Lefler on IRC
----------------------------/ <>
The viewpoints expressed above are entirely false, and in no way
represent Alexei Kosut nor any other person or entity. /--------------

Received on Monday, 13 November 1995 18:01:16 UTC