Nope you didnt get what i meant. Ok it try to explain better.
Phone (TCP) -> NAT -> Sip server(TCP) Phone can connect ok to server, because phone can initiate connection from LAN to SIP server. But NAT device has now NAT port forwardings, so SIP server never can establish connection to SIP phone. All works tough, because pone keeps TCP cnnection alive and SIP server uses open connection. But SIP rfc says that need to add Contact to any request/resposne what can establish dialog, in current case phone contact is DUMMY, server never can contact to it. What that value must be in this case ? Local IP address:local_port or public IP address:local_port ? Harsha. R wrote: > Not sure if this helps. Just let me know. > > Simple Traversal of UDP Through NATs and TCP too (STUNT), which > extends STUN to include TCP functionality > > http://nutss.gforge.cis.cornell.edu/stunt.php > > Regards > Harsha > > On 11/01/2008, Ivar Lumi <[EMAIL PROTECTED]> wrote: > >> Hi, >> >> I'm sure there are a lot of discussions about it here, so don't shoot me >> on this. >> >> What must be Contact address if SIP client is behind NAT and it uses TCP >> or SSL ? >> The problem i see: >> SIP server never can't establish connection to SIP client, so server >> must use active TCP connection. No problem with that, but again Contact >> here turns to be useless in that case. >> >> With UDP simple, you STUN public IP end point and use it in contact ... . >> >> Any comments are welcome. >> _______________________________________________ >> Sip-implementors mailing list >> [email protected] >> https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors >> >> > > > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
