I have freepbx distro in serevral places and soon I will have to implement HA with Sangoma devices and I will have a sip trunk in few places. Telecom offers sip trunk with surrogate option but I have no idea on how to use it so far. I have never used that before. Telecom gave me IP address to set for surrogate agents as well. Can someone explain me what are surrogate channels or agents and how to configure it?