A TGM550 and one or more TIMs installed in a Services Router provide telephony exchange services to a branch office over IP networks. Different TIMs have access ports for different types of VoIP and analog telephones and telephone lines. You connect the telephones and lines to the ports on the TGM550 and the TIMs. VoIP telephones require connection to a Power over Ethernet (PoE) adapter or switch that is plugged into an Ethernet port on the Services Router.
VoIP capabilities on the TGM550 enable the Services Router to provide VoIP services to telephones and trunks that do not directly support VoIP. The TGM550 translates voice and signaling data between VoIP and the system used by the telephones and trunks. TIMs convert the voice path of traditional circuits such as analog trunk and T1 or E1 to a TDM bus inside the router. The TGM550 then converts the voice path from the TDM bus to compressed or uncompressed and packetized VoIP on an Ethernet connection.