S0/0:192.1.1.1     S0/0       S0/1           S0/0:192.1.1.3

DTE-------------DCE-DCE----------------DTE

                          router a                 router c                    ruoter b

// router a

int s0/0

  ip address 192.1.1.1 255.255.255.0

  encap frame-relay

  frame-relay lmi-type ansi          // set LMI type to ANSI Annex D

router rip

  network 192.1.1.0

// router b

interface serial 0/0

  ip addr 192.1.1.3 255.255.255.0

  encapsulation frame-relay

  frame-relay lmi-type ansi

router rip

  netw 192.1.1.0

// router c

frame-relay switching

int s0/0

  encap frame-relay

  clockrate 64000

  frame-relay lmi-type ansi

  frame-relay intf-type dce

  frame-relay route 100 interface serial0/1 101

interface serial0/1

  encap frame-relay

  clockrate 64000

  frame-relay lmi-type ansi

  frame-relay intf-type dce

  frame-relay route 101 interface serial0/0 100

除了定义帧中继封装和LMI信令的标准配置命令外，每个支持交换机的接口必须通过frame-relay intf-type dce命令配置成帧中继DCE

要点：

frame-relay switching

int s0/0

  encap frame-relay

  frame-relay lmi-type ansi

  frame-relay intf-type dce

  frame-relay route 100 interface s0/1 101

int s0/1

  encap frame-relay

  frame-relay lmi-type ansi

  frame-relay intf-type dce

  frame-relay route 101 interface s0/0 100