About the Avaya IG550 Integrated Gateway

The Avaya IG550 Integrated Gateway consists of the TGM550 Telephony Gateway Module and one or more Telephony Interface Modules (TIMs) that are installed in the slots on the J4350 and J6350 Services Routers to provide VoIP connectivity. The TGM550 is an H.248 media gateway that works with the TIMs to connect IP and legacy analog telephones and trunks over IP networks and enable IP telephones to communicate through analog telephone lines and trunks.

The TGM550 is also connected over a LAN or WAN to a Media Gateway Controller (MGC)—an Avaya media server running Avaya Communication Manager (CM) call processing software. The telephony services on the TGM550 are managed by an MGC located at headquarters or in a branch office. When the primary MGC is located at a remote location, the TGM550 uses standard local survivability (SLS) for partial MGC backup in the event that the connection to the primary MGC is lost. J-series Services Routers can thereby provide reliable telephony services to branch offices.

Figure 44 shows a typical VoIP topology. The small branch office shown in the expanded illustration on the right is connected over the corporate WAN to the head office through a J6300 Services Router with VoIP modules installed. The Avaya Media Gateway Controller, S8700 Media Server, and integrated Management tools at the head office manage telephony services for headquarters and the branch offices on the WAN, connecting the corporation's legacy analog telephones, VoIP telephones, PCs, and fax machines to the PSTN.