Thanks to your video, I have managed to connect a Grandstream GXW4108 gateway and an Issabel IP central. I connect the gateway with three analog telephone lines and I have managed to assign the incoming call to a specific extension in Issabel. What I can't do is make it possible to call mobile phones (I must have problems with the dialing patterns)... but what is more complicated for me to understand is how to make the extension (from Issabel) be able to choose which line (FXO) of the gateway is the one to be used. I have created the outgoing routes indicating the CID, but all the calls go out through the line connected to the FX0 of the gateway. anyway... thank you very much for the video, it has helped me a lot to start in this. Greetings from Chilean Patagonia.
