Frame Relay Address Mapping
Figure 14-1 does not even bother listing the DLCIs used for the VCs. The earlier configurations work as stated, and frankly, if you never knew the DLCIs, this network would work! However, for the exams, and for real networking jobs, engineers need to know the DLCIs, and the process of Frame Relay mapping.
Frame Relay mapping matches a next-hop IP address that sits on the Frame Relay network with the right DLCI used to send frames to that next-hop device, with the same goal as ARP on a LAN. Figure 14-2 shows the same network, this time with local DLCI values shown.