Evening All:

KX-NCP500 with IP phones on premise. Working fine. Customer would like to add one IP phone at an off premise office (home office). I have access to the firewall to open ports as needed (or port forward)

I can get the phone to have date & time on the display at the off premise end, call a phone & ring it at the premise end, ring when called at the off premise end. I can't get any audio to pass thru either direction.

Factory support says it the NCP500 must have a VPN for the off premise phone to work.

Has anyone found a way to get it to work without a VPN?

Thanks in advance. Edward

I would say no as it does not have the media gateway like the NS systems

It is all down to the way the header is written. It tells the phone where to go but would be internal address that goes out not the IP of the internet so it does not know where to go back too

Only thing you could try is port forward 12000 to 12511 UDP to the dsp card ip address but would not like to rely on it working all the time if any

I have already forwarded ports 12000 - 12255 to the DSP address, but can try the additional port range you have suggested.