r- tual circuits (VCs). These messages tell routers when a frame-relay PVC is available. LMI messages are sent on a predefined PVC. The LMI type and PVC in use can be seen with the show interface command: Router-A# sho int so/o Serialo/o is up, line protocol is up Hardware is PowerQUICC Serial MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation FRAME-RELAY, loopback not set Keepalive set (10 sec) LMI enq sent 85, LMI stat recvd 86, LMI upd recvd 0, DTE LMI up LMI enq recvd 0, LMI stat sent 0, LMI upd sent LMI DLCI 1023 LMI type is CISCO frame relay DTE FR SVC disabled, LAPF state down Broadcast queue 0/64, broadcasts sent/dropped 0/0, interface broadcasts 0 Last input 00:00:03, output 00:00:03, output hang never Last clearing of "show interface" counters 00:30:11 Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 0 Queueing strategy: weighted fair Output queue: 0/1000/64/0 (size/max total/threshold/drops) Conversations 0/1/256 (active/max active/max total) Reserved Conversations 0/0 (allocated/max allocated) Available Bandwidth 1158 kilobits/sec 5 minute input rate 0 bits/sec, 0 packets/sec 5 minute output rate 0 bits/sec, 0 packets/sec 86 packets input, 1758 bytes, 0 no buffer Received 0 broadcasts, 0 runts, 0 giants, 0 throttles 1 input errors, 0 CRC, 1 frame, 0 overrun, 0 ignored, 0 abort 88 packets output, 1145 bytes, 0 underruns 0 output errors, 0 collisions, 1 interface resets 0 output buffer failures, 0 output buffers swapped out 2 carrier transitions DCD=up DSR=up DTR=up RTS=up CTS=up Three forms of LMI are configurable on Cisco routers: cisco, ansi, and q933a (Annex A). The DCE device (telecom switch) usually determines the type of LMI. The default LMI type on Cisco routers is cisco. The LMI type can be changed with the frame-relay lmi-type interface command: Router-A(config-if)# frame-relay lmi-type ? cisco q933a Local Management Interface (LMI) Congestion Avoidance in Frame Relay Frame relay includes provisions for congestion avoi