[OpenSIPS-Users] Transfer issue

Iñaki Baz Castillo ibc at aliax.net
Tue Nov 17 12:46:01 CET 2009

El Martes, 17 de Noviembre de 2009, Bogdan-Andrei Iancu escribió:

> > Imagine the b2bua routes/generates the call to a proxy which does
> > parallel forking so b2bua receives two 183 with different To-tag and, of
> > course, different SDP (sess-id, sess-version...).
> >
> > The b2bua replaces the received To-tags in an *unique* new To-tag to be
> > used in the upstream leg.
> >
> > This is a bug since the UAC will receive two 183 with same To-tag but
> > different SDP so it must ignore the second SDP (a SDP cannot change
> > during an early-dialog).
> are you sure about this behaviour ? is it stated by  RFC3261?

It's stated in RFC 3261 and also in RFCXXXX (SDP). I'm 100% sure and I already 
convinced to Sippy b2bua and SEMS developers ;)


> > If the b2bua doesn't replace the To-tag then the problem automatically
> > dissapears, but then it's not a b2bua :)
> it does change :)

Ok, but a different To-tag is required for each diferent To-tag received from 
UAS's. If not, the above problem arises :)

Iñaki Baz Castillo <ibc at aliax.net>

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