Subject: RE: [SIP] Caller receives responses

From: Sean Olson <[email-masked]>
Date: Fri, 23 Jun 2000 11:06:01 -0500 (CDT)

> 
> If you fork REGISTERs (I'm not sure why you'd do this -- perhaps
> towards some sort of redundancy?), are there any potential
> problems with only returning one 200?  The only other request
> I can possibly see problems with (because you might get a response
> from a UA that ultimately you wouldn't have been interested in)
> is OPTIONS.  (Of course, unknown methods are forwarded like
> OPTIONS.)

I can think of a couple of good applications for forking REGISTER and other
non-INVITE requests where you definitely DO care about receiving
ALL of the 200 class responses. If a UA already has to deal with
multiple 2xx response for an INVITE, is it really so different
to do this for non-INVITE requests as well?

sean

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From: Jonathan Rosenberg <[email-masked]>
Date: Fri, 23 Jun 2000 15:30:45 -0400

> to do this for non-INVITE requests as well?

Yes, because it is impossible.

Multiple 200 OK for INVITE only works because you can ACK each one
individually. With non-INVITE, the only way to retrigger a response
retransmission is a request retransmission. But, request retransmissions
are not for a specific response; thus, it would be impossible to
reliably transmit multiple 200 OK to non-INVITE.

I do not believe there is really a need for multiple 200 OK for
non-INVITE, in any case.

-Jonathan R.

-- 
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