This question is more appropriate for the SIP or SIPPING mailing lists. However, to answer your question: see draft-ietf-sip-outbound-10.txt. -d > -----Original Message----- > From: Dangi [mailto:sip.gyan@xxxxxxxxx] > Sent: Friday, August 31, 2007 5:47 AM > To: ietf@xxxxxxxx > Subject: Behind the NAT registration > > Hi All, > Assume a scenario where SIP UA is running behind a NAT. At > the time of registration, what should be the address put in > "Contact" header i.e. local/public IP? > If UA populates its local IP in "Contact" header, then that > can't be used to terminate call. > In general, its UA who determine its NAT bindings and > poupulate in "Contact" header or registrar determine it from > source of IP packet and send back in "Contact" header in 200 OK? > > What is the best way to enable call termination on this UA > behind NAT i.e rport,stun,etc? > > Thanks a lot, > /raj > _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf