Cisco IOS Wide-Area Networking Configuration Guide - Free Books

Configuring Frame RelayCustomizing Frame Relay for Your NetworkFigure 29PPP over Frame Relay ScenarioPPP sessionAsyncFrame RelaynetworkCorporate HQISDN12706Enabling PPP over Frame RelayBefore PPP over Frame Relay is configured, Frame Relay must be enabled on the router using theencapsulation frame-relay command. The only task required in order to implement PPP over FrameRelay is to configure the interface with the locally terminated PVC and the associated virtual templatefor PPP and IP, as described in the following section.After configuring Frame Relay encapsulation on the Cisco router or access server, you must configurethe physical interface with the PVC and apply a virtual template with PPP encapsulation to the DLCI.To configure the physical interface that will carry the PPP session and link it to the appropriate virtualtemplate interface, perform the following task in interface configuration mode:CommandRouter(config-if)# frame-relay interface-dlci dlci[ppp virtual-template-name]PurposeDefines the PVC and maps it to the virtual template.For an example of configuring PPP over Frame Relay, see the section “PPP over Frame Relay Examples”or “PPP over Frame Relay DCE Example” later in this chapter.Configuring Frame Relay SubinterfacesFor a general explanation of Frame Relay subinterfaces, read the following section, “UnderstandingFrame Relay Subinterfaces.”To configure the Frame Relay subinterface and define subinterface addressing, perform the tasks in thefollowing sections:• Defining Subinterface Addressing (Required)• Configuring Transparent Bridging for Frame Relay (Optional)31