Trunk Gateway

The Trunk Gateway provides an access interface between traditional Public Switched Telephone Network (PSTN) circuit-based networks and packet networks. Examples of the PSTN trunk interfaces are Integrated Services Digital Network (ISDN) User Part (ISUP), Primary Rate Interface (PRI), Multi Frequency (MF) and Digital Tone Multi Frequency (DTMF). The Trunk Gateway may also support an interface for line based Generic Requirement GR-303/TR-08 remote terminals. The Trunk Gateway may be connected to the network via various bit-rate and physical layer interfaces. A Call Agent provides the specific call control, call processing and other management functions for the trunks terminated on the Trunk Gateway.