This question probably was asked many times, but I'm still not able to figure out how to setup a SIP trunk between CCM (v.4.1) and CME. I read all articles about IP-to-IP SIP protocol, played around with different setting, but no luck. Can you point me to the right direction? Example configuration will be very helpful. Basically I need to make calls between 4 digits extensions between offices and to route OffNet calls.