How to Dual Register SBC with SIP Provider?
I've been struggling to get this resolved for a while now and it really has to do only with Outbound Calls to the SIP Provider. Inbound seems to work fine...
The problem seems to be with the way we have configure surrogate agent to authenticate on behalf of the ECB. ECB seems to have a limitation of only having 1 SIP port when it sources itself to the SBC. With this limitation it uses the wrong authentication username and password on the redundant/secondary trunk.
I have the following call flow / setup.
Cisco Call Manager (PBX) ---> ECB ---> SBC ---> Local Policy /