GEneral question about SIP trunking with CCM 5.1
a) What is the best configuration document for setting up SIP devices as CCM extensions through an external SIP proxy?
b) Can you get full SIP Line feature functionality (even extended) through a SIP trunk?
c) Do the SIP extensions connected through the mentioned SIP trunk always need to SIP register to CCM? Any way to avoid this need through configuration?