Is it possible to call from one port to another? For example, I have a phone in port 1 and 2. Can I call the other phone without the need to make any sort of external call?
Call from one port to another on the same ht818?
you can try to make a direct call IP -> IP,
but you need a voip server or similar support that allows you to convey the voice call,
Unlike the GXW42XX gateways, the HT does not support Inter-port calling.