With 8 telephone interface ports, the GXW4108 FXO Analog Gateway from Grandstream Networkshelps bridge the gap between traditional telephones and VoIP phone systems. This gateway supports PSTN/PBX analog trunk lines, along with an SIP trunk interface, to effectively convert traditional PSTN-based telephone calls into a VoIP signal to be transmitted over an IP-based connection. In addition to 8 telephone ports, you can also take advantage of a dedicated video surveillance port complete with support for real-time video feeds, CIF resolution, and a 30fps frame rate.