- From: <rlgray@raleigh.ibm.com>
- Date: Tue, 29 Jul 1997 11:34:40 EST
- To: HTTP Working Group <http-wg%cuckoo.hpl.hp.com@hplb.hpl.hp.com>
I agree with Scott that Public and Allow should be end-to-end, but it would be nice to hear from some client implementers on this issue... ** Reply to note from "Scott Lawrence" <lawrence@agranat.com> Fri, 25 Jul 1997 09:47:21 -0400 > > > JM> (8) [For the moment, two possible alternatives here!] > > I'm afraid that I can't decipher whether it is (8a) or (8b) that I > like or whether I don't like either one. Simply stated, I would > prefer that proxies never modify either Public or Allow headers; > they should always be end-to-end headers. I choose this alternative > because I think it is easier for a client to discover what is going > on this way. > > If proxies DO modify the Public and Allow headers, an end-client > can't tell whether it is the origin server or the proxy that doesn't > support what it wants because it sees the same response from both. > While it is true that the client may have another way to reach the > origin server, if that is not the case there will be no way for the > user to determine that the proxy is the problem. Since many users > are behind proxies they cannot get around, there would be no way for > them to discover that the reason they can't use some service is that > the proxy is missing something. > > If proxies DO NOT modify Public and Allow headers, the methods > supported by the origin server can be discovered by sending an > OPTIONS request, and the methods supported by each proxy can be > discovered by sending an OPTIONS request with a Max-Forwards > header. > > This would be a slight change to RFC 2068 definition for the > treatment of these headers by proxies, but as far as I can tell > there are no deployed 2068 proxies out there yet, so I don't think > that is a practical concern. Even if there were, a client could > detect that a proxy was 2068-only by sending OPTIONS with a > Compliance header to the proxy and get back an OPTIONS response > without a Compliance header. > > -- > Scott Lawrence EmWeb Embedded Server <lawrence@agranat.com> > Agranat Systems, Inc. Engineering http://www.agranat.com/ > > Richard L. Gray chocolate - the One True food group
Received on Tuesday, 29 July 1997 08:39:39 UTC