CCNA实验之---背对背帧中继配置

  帧中继（ Frame Relay）是一种用于连接计算机系统的面向分组的通信方法。它主要用在公共或专用网上的局域网互联以及广域网连接。大多数公共电信局都提供帧中继服务，把它作为建立高性能的虚拟广域连接的一种途径。帧中继是进入带宽范围从56Kbps到1．544Mbps的广域分组交换网的用户接口。CCNA考试有时会抽到此题，掌握一下没有坏处。

   下面我们用模拟器来做这个试验，用路由器来模拟帧继环境。

实验环境：两台路由，串口相连

实验要求：用路由器模拟帧中继环境，FR-SW为帧中继交换机，同时使用缺省路由使全网互通

实验拓扑：

一：配置帧中继及连通性

fr-sw的配置：

fr-sw(config)#fram-relay switching    启用帧中继交换机功能

fr-sw(config)#int loopback 1

fr-sw(config-if)#ip add 1.1.1.1 255.255.255.0

fr-sw(config-if)#int s1/0

fr-sw(config-if)#ip add 192.168.10.1 255.255.255.0

fr-sw(config-if)#no sh

fr-sw(config-if)#encapsulation frame-relay  封装帧中继

fr-sw(config-if)#fram-relay intf-type dce     设为时钟提供端

fr-sw(config-if)#clock rate 64000     设定时钟为64000

fr-sw(config-if)#fram-relay map ip 192.168.10.2 102 broadcast

-->启用静态映射，这个DLCI号码(102)同时也是对端设备的DLCI，两端必须相同

fr-sw(config-if)#fram-relay map ip 192.168.10.1 102 broadcast 

-->指向自已，是为了PING通本路由器的接口

fr-sw(config)#ip route 0.0.0.0 0.0.0.0 0.0.0.0

 

R1的配置：

r1(config)#int loopback 2

r1(config-if)#ip add 2.2.2.2 255.255.255.0

r1(config)#int s0/0

r1(config-if)#ip add 192.168.10.2 255.255.255.0

r1(config-if)#no sh

r1(config-if)#encapsulation fram-relay

r1(config-if)#fram-relay map ip 192.168.10.1 102 broadcast   与对端相同

r1(config-if)#fram-relay map ip 192.168.10.2 102 broadcast   指向自已

r1(config)#ip route 0.0.0.0 0.0.0.0 0.0.0.0   启用缺省路由

 

 

调试验证：

fr-sw的帧中继映射关系：

fr-sw#sh frame-relay map
Serial0/0 (up): ip 192.169.10.1 dlci 102(0x64,0x1840), static,
              broadcast,
              CISCO, status defined, active
Serial0/0 (up): ip 192.169.10.2 dlci 102(0x64,0x1840), static,
              broadcast,
              CISCO, status defined, active

 

R1的帧中继状态：

r1#sh frame-relay pvc

PVC Statistics for interface Serial0/0 (Frame Relay DTE)   s0/0为DTE端

              Active     Inactive      Deleted       Static
  Local          1            0            0            0
  Switched       0            0            0            0
  Unused         0            0            0            0

DLCI = 102, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial0/0

  input pkts 0             output pkts 0            in bytes 0        
  out bytes 0              dropped pkts 0           in FECN pkts 0        
  in BECN pkts 0           out FECN pkts 0          out BECN pkts 0        
  in DE pkts 0             out DE pkts 0        
  out bcast pkts 0          out bcast bytes 0        
  pvc create time 00:03:12, last time pvc status changed 00:02:32

 

R1的帧中继映射;

r1#sh frame-relay map
Serial0/0 (up): ip 192.168.10.1 dlci 102(0x64,0x1840), static,
              broadcast,
              CISCO, status defined, active
Serial0/0 (up): ip 192.168.10.2 dlci 102(0x64,0x1840), static,
              broadcast,
              CISCO, status defined, active

 

连通性测试：

FR-SW上连通性测试：

fr-sw#ping 2.2.2.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2.2.2.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 28/31/32 ms
fr-sw#ping 192.168.10.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.10.2, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/30/36 ms

 

R1上连通性测试：

r1#ping 1.1.1.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 1.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/28/72 ms
r1#ping 192.168.10.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.10.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 12/28/32 ms