The MTG series are E1/T1 Digital VoIP Gateways that seamlessly connect VoIP and the legacy PSTN networks (legacy PBX or E1/T1 service providers) , scalable up to 63 E1 or T1 lines. Supporting ISDN PRI, SS7 and R2 MFC signaling, various voice codecs and SIP protocol, the MTG series are able to meet the vast VoIP needs of SMEs, large enterprises, service providers, carriers, call centers.