Chapter 3. Terminal Menu Operation and Structure3-32 Express 6100/6120 User Manual 61200176L1-1» Configuration/Frame RelayFrame Relay is a connection-oriented service requiring circuits to beconfigured by your carrier to establish a physical link between two ormore locations. Multiple virtual circuits (which appear as virtualpoint-to-point links) can be run through the same physical connection.There are two types of virtual circuits supported in Frame Relay: Per-manent Virtual Circuits (PVC) and Switched Virtual Circuit (SVC).PVCs are like dedicated point-to-point private lines. Since the physi-cal connection is always there in the form of a leased line, call setupand tear down is done by a carrier via a network management system.SVCs require setup and tear down and are generally not availablefrom Frame Relay carriers. Virtually all Frame Relay communicationsis done using PVCs. The Express 6100/6120 supports PVCs only.A number called the Data Link Connection Identifier (DLCI) identifieseach virtual circuit within a shared physical channel.Figure 3-8 shows the Frame Relay menu.Figure 3-8. Configuration/Frame Relay Screen
