Re: [Serusers] rfc 3262 support

I think the idea is that a proxy can send a provisional response to the UAC and thus take responsibility for the transaction towards the (real) UAS, just like sending a 100 Trying... before forwarding. The UAS has not yet received the INVITE (or whatever message we are talking about) and thus to tag is not yet set.

g-) Klaus Darilion wrote: > Hi Kamal! > > I reconsidered by previous answer and found that there is no Cseq > Problem as CSeq may have gap. > > But reading your snippet: I've never seen any client yet sending > provisional responses without to-tag. Thus, even if the proxy could > generate reliable responses it wouldn't be used often. > > regards > klaus > > Kamal.Mann(a)t-systems.com wrote: >> Hi Darilion >> Please check the following snippet from rfc-3262 >> "An element that can act as a proxy can also send reliable provisional >> responses. In this case, it acts as a UAS for purposes of that >> transaction. However, it MUST NOT attempt to do so for any request >> that >> contains a tag in the To field. That is, a proxy cannot generate >> reliable provisional responses to requests sent within the context >> of a >> dialog. Of course, unlike a UAS, when the proxy element receives a >> PRACK that does not match any outstanding reliable provisional >> response, >> the PRACK MUST be proxied." >> >> Regards >> Kamal Mann >> >> -----Original Message----- >> From: Klaus Darilion [mailto:klaus.mailinglists@pernau.at] Sent: >> Thursday, October 19, 2006 3:03 PM >> To: Greger V. Teigre >> Cc: Mann, Kamal; serusers(a)lists.iptel.org >> Subject: Re: [Serusers] rfc 3262 support >> >> AFAIK PRACK is a client feature and is end to end. Thus, ser >> supports PRACK as any other generic SIP request. >> >> Maybe you could fake PRACK requests or responses between a PRACK >> capable >> >> client and the proxy, but this will cause end-to-end CSeq mismatch >> and would require a dialog stateful proxy to adapt the CSeqs. >> >> regards >> klaus >> >> Greger V. Teigre wrote: >>> AFAIK, this RFC is not implemented yet. As for a list, there is >>> none right now, but it's on the to-do list :-) >>> g-) >>> >>> Kamal.Mann(a)t-systems.com wrote: >>>> Hi All >>>> >>>> Do SER supports 'rfc 3262 Reliability of Provisional Responses in >>>> SIP'? Is there any list of standards supported by SER available?? >>>> >>>> >>>> >>>> Regards >>>> >>>> Kamal Mann >>>> >>>> >>>> >>>> >> ------------------------------------------------------------------------ >> >>>> _______________________________________________ >>>> Serusers mailing list >>>> Serusers(a)lists.iptel.org >>>> http://lists.iptel.org/mailman/listinfo/serusers >>>> >>> >> ------------------------------------------------------------------------ >> >>> _______________________________________________ >>> Serusers mailing list >>> Serusers(a)lists.iptel.org >>> http://lists.iptel.org/mailman/listinfo/serusers > >