The Call Agent provides call processing, call control, feature control and Operations Administration Maintenance & Provisioning to manage services for a packet network comprised of multiple types of media gateway endpoints. The network itself may transport traffic over many types of packet switching fabric, such as IP, Ethernet, ATM or Frame Relay. The Media Gateways (i.e., Access and Trunk Gateways) may be connected to the network via various bit-rate and physical layer interfaces. The Call Agent may use one or many different control protocols to communicate with the media gateways. The Call Agent provides the intelligence and capability to control the overall node-to-node signaling for both on-net and off-net calls. This is sometimes referred to as a âSoftswitchâ.