sip integration with switchvox pbx

[febinattingal]

Hi team,

We have Cisco Call Manager 6.1 solution and one of our branch have SwithVox PBX (SIP-based PBX)Solution.we integrated both using SIP Trunk via VPN Tunnel. we configured MTP in CCM side .Other PBX like Awaya is working fine with this PBX.

After these configurations we can able to make calls with Swithvox PBX,But Swithvox users unable to hear our voice and ccm users able to hear their voice.

We are not done any SIP configuration in gateways....is it required...

Please suggest what are the proper configurations we want to do and how to trouble shoot this oneway issue....

Or is it the problem of SwithVox PBX side..?

[Nicholas Matthews]

Normally when you have a VPN involved and you have one way voice, it's either:

-Firewall blocking RTP ports (16384-32767 UDP)

-VPN is allowing direct connectivity between endpoint and CUCM, but not endpoint to another endpoint (RTP stream)

In this case the RTP stream from phones on the CUCM side aren't making it to the SwitchVox. Make sure the default gateway of the IP phones can ping the address of the SwitchVox.

You can also take a look at the SIP signaling (either on the pbx or in CUCM detailed traces) to see if the incoming INVITE or ACK from the PBX has the correct media address in the SDP.

hth,

nick