Hello,

This answer is somewhat based on previous questions that you have asked.

> Who forwards Registrations to Asterisk or PBX, and who lets Kamailio
> maintain Registrations?

As Alex said, it depends on what you are trying to accomplish. In addition, I would say that it depends on the call scenarios you expect to see.

Kamailio is more efficient at processing and routing SIP messages, so I let it do as much of the work as possible. I would only forward calls to Asterisk in order to do the things that Kamailio cannot, like answer the call in order to play an automated message, an IVR, record DTMF etc. Kamailio can implement calling queues, but I chose to put those in Asterisk as well as it has additional functionality.

For a normal call from user A to user B, you don’t need to involve asterisk at all.

With kind regards
Pan B. Christensen
Developer
Phonect AS