Hi, I am pretty sure it is still useful in certain cases, for example, if you have a NAT and NAT device is not SIP aware. Using rport/received together with you can get your public ip/port seen by the proxy and when reregistering provide your public ip/port to the proxy. By keeping your connection to NAT device persistent incoming call from proxy should still be properly routed. Also, in this case you should use symmetric sip.
Nenad -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Iñaki Baz Castillo Sent: Wednesday, July 23, 2008 5:11 PM To: [email protected] Subject: [Sip-implementors] Is "received" and "rport" used in SIP TCP? Hi, I'm realizing that "received" and "rport" are completely useless in SIP TCP: - The client MUST reply using the existing conecction that creates the incoming request. So for now "received" and "rport" are not used at all. - If the connection fails during the reply then the UAS/proxy must perform steps in RFC3263 as failover, and those steps mean sending the response to "sent-by". So again "received" and "rport" is not used. - Also take in mind that when a UAC establishes a TCP connection with UAS it uses an arbitrary source port so if the connection fails the UAS cannot open a new connection to that original source port (except using "alias" extension that it's not relevant now). So, the conclusion is: "received" and "rport" parameters are completely useless in SIP TCP, is it? Thanks for any comment. -- Iñaki Baz Castillo _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors --------------------------------------------------------------------------- This email communication may contain CONFIDENTIAL, PRIVILEGED and/or LEGALLY PROTECTED information and is intended only for the named recipient(s). Any unauthorized use, dissemination, copying or forwarding is strictly prohibited. If you are not the intended recipient and have received this email communication in error, please notify the sender immediately, delete it and destroy all copies of this email. --------------------------------------------------------------------------- _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
