Subject: [SIP] Legal loop detection-Hash calculation

From: [email-masked]
Date: Thu, 17 Aug 2000 15:30:44 -0500

For the legal loop detection hash calculation,
Why do we need the From and To to compute the hash?
I suppose the ReqURI and the CallID are sufficient to compute
the hash!!

The use of cSeq number as mentioned in the rfc2543bis would
be a problem issue since if the proxy insists on being on the
path, a reinvite won't have the same cSeq number.

-Deepak

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From: Jonathan Rosenberg <[email-masked]>
Date: Thu, 17 Aug 2000 22:25:42 -0400

> I suppose the ReqURI and the CallID are sufficient to compute

By using to, from call-ID and CSeq, you get the nice property that the
branch-ID of the request is a complete transaction identifier. But,
this is an implementation dcision. As far as the algorithm is concerned
(detecting spirals), request URI alone is all that is needed.

> path, a reinvite won't have the same cSeq number.

Huh? This is a totally separate transaction.

-Jonathan R.

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