Subject: Redirect

From: Pat Calhoun <[email-masked]>
Date: Thu, 11 Jan 2001 06:57:31 -0800 (PST)

All,

The current base protocol specification states that a redirect server returns
a response to the requestor with the error code set to redirect. However, some
discussions we have been having recently on this list implies that redirect
and proxy servers may not actually support all extensions, and may only
support the bare minimum required for packets to be forwarded to the home
server.

Therefore, I question how such servers would ever know how to set the command
code field to the correct response. So, if we really need to support the above
case, one of the following needs to be done:

1. Do nothing and require that proxies/redirect servers support extensions
(this is a valid requirement).

2. Make sure that the redirect indication is returned in an MRI
(Message-Reject-Ind) message. However, one does question how request/responses
are matched up properly, and the details of this need to be refined

3. A MUCH more drastic change, and one I am not sure that I like but I am
adding for completeness. No longer distingush request from responses, but
rather make use of the bits in the message header to distinguish whether the
message is a request or a response. So an Access message would have the
request mode (when bits are set), or a response (when the bits indicate a
response). This *seems* clean, but is a huge change for implementations and
the protocol.

I think that the simplest is #2 above, but I am opening up this can of worms
now to get a feel for how people think their proxies will operate.

PatC