Kylink's VoIP Gateway as named NIPX-GW816II is a cutting-edge product that supports protocol H.323 and SIP. It's the best gateway to span PSTN and Internet within state of the art design.
NIPX-GW816II has type A and B, Maximum 16 ports in type A and 8 ports in type B for your reality configuration.
Obviously, the GW816II will take its place to routing your call from existing PBX to PSTN or Internet automatically. It's not only working as gateway but also providing the simple functions of PBX such as Hotline caller ID .etc. In addition, your calls to VoIP will go through PSTN once the Ethernet failure detected.