In a telephony system, we must have a voice gateway to connect to PSTN. I think of a situation and want to know your ideas:
If we use H.323 as the signaling protocol and configure POTS dial-peers to send calls to PSTN, anyone who know the address of the H.323 gateway can use this gateway to make calls to PSTN (just send the calls to the voice gateway and then the VG sends the calls to PSTN)
How can we prevent this?
P/S: if we use SIP or MGCP, will the situation be the same?