2008/10/13 Attila Sipos <[EMAIL PROTECTED]>: >>>but I really wonder >>>which is the difference between this case and the above case in which UA1 >>>receives incoming requests from the proxy using the port 11111 used for >>>registration. > > I agree, I don't think there is much difference. > Except that for the case of the registrar (port 11111), a DNS lookup of the > Via will most-likely yield the address of the registrar.
I can confirm that the SIP devices I've used with SIP TCP behind NAT allow requests from proxy coming by the TCP connection used for registration. In fact, a common technique is the proxy/registrar to mantain the connection open by requiring REGISTER every 30 secons (< 32 = 64xT1), and other option is the client to use PING-PONG TCP connection keepalive. But since it's not defined in RFC 3261 I'm afraid of this methods... Thanks a lot. -- Iñaki Baz Castillo <[EMAIL PROTECTED]> _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
