Re: 301/302

On Fri, 5 Sep 1997, Scott Lawrence wrote:

> 
> >>>>> "RTF" == Roy T Fielding <fielding@kiwi.ics.uci.edu> writes:
> 
> RTF> It will be a while before applications can transition to using all of the
> RTF> features of HTTP/1.1 without looking at the User-Agent or Server field
> RTF> first, but we have to start somewhere.
> 
>   How so?  If a server gets a request labeled HTTP/1.1, it should
>   treat it as one and respond with 1.1; the complexity of looking at
>   User-Agent values and making some decision based on them is too much
>   to contemplate (especially since many browsers lie in thier
>   User-Agent headers).
> 

I agree with you that having the server keep a table of User-Agents in
order to know the client's version is completely impractical.  But if
a server "demands its rights" and sends 303 and 307 in response to
HTTP/1.1 requests then as soon as HTTP/1.1 proxies are deployed a lot
of client/server transactions will break.

I hope I am wrong, but we seem to have painted ourselves in a corner
here.  On the one hand we have decided that the client's version
should not be communicated to the origin server when there are proxies
(all version information is hop-by-hop).  And on the other hand we
have created end-to-end headers (e.g. 303/307) which are not
reasonably handled by HTTP/1.0 clients.  It seems that if there is no
end-to-end version information we can't have new end-to-end headers
that will break on HTTP/1.0 clients.

John Franks 	Dept of Math. Northwestern University
		john@math.nwu.edu

Received on Friday, 5 September 1997 12:25:34 UTC