El Lunes, 15 de Diciembre de 2008, Bogdan-Andrei Iancu escribió: > Hi Iñaki, > > Iñaki Baz Castillo wrote: > > 2008/12/11 Bogdan-Andrei Iancu <[email protected]>: > >> A) contact info versus network info > >> > >> When considering a REGISTER request, you have two sets of information: I > >> - registered contact ; II - network info (source IP/port, proto, local > >> socket where the request was received on). > >> When comes to determine the destination for pinging, right now, the > >> logic uses the network info (as more or less NAT at network level). > >> But, according to RFC 3261, the REGISTER request may carry whatever > >> contact, like a REGISTER via UDP may register a contact for TCP (or > >> vice-versa). In case of NAT, this will not work at all (as we assume > >> that the source of REGISTER and registered contact point to the same > >> network location). > > > > Well, but it is obviously the only way. The registrar can never know > > if the private address in the Contact is behind the same public IP as > > the received one. > > > > AFAIK registering a Contact different that the address of the UA > > sending the REGISTER is just used in IMS (some exotic stuf...). > > > > Is there any other case in which the REGISTER Contact could be different? > > Generic case of third party registration (but such a scenario in NAT > envs. is completely broken).
Humm, but the above is not 3rd Party Registration (3rd Party Registration means: "From: al...@domain, To: b...@domain, Contact: al...@ip". > > Ufortunatelly I know no UA's sending a TCP Contact via UDP. Do they > > exist? > > I do not, but from SIP point of view is perfect possible - like a device > that supports both TPC and UDP, may use UDP to register both UDP and TCP > contacts.. I hope that any UA behind NAT who wants to register a TCP location will use TCP. If not it's just impossible to contact him! Thanks. -- Iñaki Baz Castillo _______________________________________________ Users mailing list [email protected] http://lists.opensips.org/cgi-bin/mailman/listinfo/users
