new contact is registered ERROR

[richtheo]

I have a setup with a 3CX server v7.1 on WS03 on a hosted server (public IP address). I am connecting Linksys SPA941 VOIP phones from remote offices which have simple broadband connections and cheapo broadband firewall/routers. From one office which has a Thomson Speedtouch 585v7 broadband router the phones work fine - No need for SIP Tunnels or VPNs. However from the other office, although the phones seem to register with the server they don't ring when called. This office has a Netgear DG834G broadband router. I think i can see the source of the problem-

When a phone extension 101 registers from the good office, you get the message:-
14:59:06.825 [CM504001]: Ext.101: new contact is registered. Contact(s): [sip:[email protected]:54660/101]
In this case, the server knows the phone via the public IP address of its broadband connection which means that it can be rung. Good.

When a phone extension 151 registers from the problem office, you get the message :-
14:59:38.450 [CM504001]: Ext.151: new contact is registered. Contact(s): [sip:[email protected]:5063/151]
The registration is reporting 192.168.1.109 which is the temporary IP address of the phone on the LAN in the office, which cannot be routed from the server. Bad.

Any ideas ?

 

[leejor]

Are the phones all set to use a STUN server? Does each one have a unique port number...ie. 5060, 5061, 5062.... Has the router been set to forward each of those ports to the (fixed) IP of each of the sets?

 

[richtheo]

ok thanks for the pointers. By enabling STUN and setting the STUN server to the same domain name as the server, it works fine and the "new contact is registered" message reports:
21:40:06.356 [CM504001]: Ext.151: new contact is registered. Contact(s): [sip:[email protected]:5063/151, sip:[email protected]:5063/151]

And it all works. Unforunately the 3CX phone configuration guide for the SPA941 makes no mention of the need for these settings. Presumably this is because the configuration guide is intended for people configuring for LAN based 3cx servers rather than internet based ones.

 

[leejor]

Yup, there are a few more "tricks" to getting remote extensions to work. The three things i mentioned will usually fix most problems.