3GPP owns the IMS specification, not the IETF. I know there was a recent contribution to 3gpp for using STUN (and TURN and ICE) for NAT traversal. In the IETF, STUN is a standard (RFC3489), TURN is being standardized in the BEHAVE working group and ICE (which is related to STUN and TURN) is being standardized in the MMUSIC working group. A list of working groups, their documents, and their mailing list information is available from http://www.ietf.org. As to 'are there more problems apart of RTP packets?', if you're asking if NATs cause problems for things other than RTP, the answer is yes. The BEHAVE working group is chartered to describe the best practices around NATs (for the NATs and for applications that hope to run over them). For some additional SIP specific techniques for dealing with NATs, see also draft-ietf-sip-outbound-04.txt. -d > -----Original Message----- > From: Ashfaaq H Poonawala [mailto:pashfaaq@xxxxxxxxxxx] > Sent: Thursday, October 19, 2006 9:11 AM > To: ietf@xxxxxxxx > Subject: NAT TRAVERSAL IN SIP THROUGH IMS > > Dear All, > I am a Masters Student at Southern Methodist University, Dallas TX. > > I am doing a project on NAT traversal in SIP in the IMS > network. I am discussing the problems for the RTP packets > while NAT traversal. One of the solution to it is the STUN > and TURN servers. > > I would really appreciate if I were to get more details in > it. Also are there more problems apart of RTP packets? > > Thanks, > Ashfaaq Poonawala > _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf