Thanks, but it still surprise me. Although my main office and branch is connected through VPN Tunel which is open on all port. I am still not able to make it works. I was wondering may be that's why tadiran also selling Sentinel gateway.
I think I gave up. I just feel I was choosing the wrong IPPBX and not too flexible such as Asterisk.
Tadiran support also doesn't help unless you buy Sentinel gateway.
