bhouse

This might be related to a NAT issue at the corporate office (could be at the satellite offices as well). Are these Nortel H.323 phones, and what type of softphone?

JamieC7

i2004 IP Phone and the i2050 Softphone

What would I look for to check the NAT issue?

Thanks!

Megahertz

Ok, This is a common problem with IP phones. The situation is this. Each of your satalite offices have a VPN connection back to the main office...
for example
Head office 192.168.1.x IP phone is 192.168.1.50
Remote office 1 192.168.2.x IP phone 192.168.2.50
Remote Office 2 192.168.3.x IP phone 192.168.3.50

when the phone in office 1 call the head office it has to make a connection back the the BCM which is in the 192.168.1.x network This works as there is a VPN connection back from the 192.168.2.x network

But when a call is made from office 1 to office 2 something special happens. A connection is made from each phone back to the BCM at the main office, Once the dialing phone determins that the other phone is also an IP phone a second connection is made directly from one phone to the other. 192.168.2.50 tries to connect to 192.168.3.50 but because there is no information in the routing table on how to connect to that phone the voice path drops. The call seems to continue because the origonal path is still intact and only call progresss information is being trasfered.

So much for the Long winded info.

Here is how you fix the problem. You have to create a MESH Vpn network. Every remote office has to have a vpn to every other remote office.

For example, you would need a tunnel from the head office to remote office 1, and a tunnel from remote office 1 to remote office 2, and a tunnel from remote office 2 to the main office, and a tunnel from remote office 1 to remote office 3 and a tunnel from remote office 2 to remote office 3 and a tunnel from remote office 3 to the head office. And so on and so on.

If you have any questions let me know.

Good Luck