Router Configuration<11>
广域网协议的封装
Target:
掌握广域网协议的封装类型和封装方法
实验原理:
常见广域网专线技术有，DDN专线、PSTN/ISDN专线、帧中继专线、X.25专线等。数据链路层提供各种专线技术的协议，主要有PPP、HDLC、X.25、Frame-relay以及ATM等。
实验拓扑图：
Step：
第一步：路由器基本配置
Router A(config)#interface serial 4/0
Router A(config-if)#ip address 172.16.2.1 255.255.255.0
Router B(config)#interface serial 4/0
Router B(config-if)#ip address 172.16.2.2 255.255.255.0
第二步：封装HDLC
Router A(config)#interface serial 4/0
Router A (config-if)#encapsulation hdlc
Router B(config)#interface serial 4/0
Router B(config-if)#encapsulation hdlc
验证广域网接口的封装类型：
Router A#show interfaces serial 4/0
Index(dec):1 (hex):1
serial 4/0 is UP , line protocol is UP
Hardware is Infineon DSCC4 PEB20534 H-10 serial
Interface address is: 172.16.2.2/24
MTU 1500 bytes, BW 2000 Kbit
Encapsulation protocol is HDLC, loopback not set
Keepalive interval is 10 sec , set
Carrier delay is 2 sec
RXload is 1 ,Txload is 1
Queueing strategy: WFQ
11421118 carrier transitions
V35 DTE cable
DCD=up DSR=up DTR=up RTS=up CTS=up
5 minutes input rate 17 bits/sec, 0 packets/sec
5 minutes output rate 17 bits/sec, 0 packets/sec
57 packets input, 1664 bytes, 0 no buffer, 0 dropped
Received 52 broadcasts, 0 runts, 0 giants
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 abort
68 packets output, 2726 bytes, 0 underruns , 0 dropped
0 output errors, 0 collisions, 0 interface resets
注意：锐捷路由器广域网接口默认封装的就是HDLC。
第三步：封装PPP
Router A#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router A (config)#interface serial 4/0
Router A (config-if)#encapsulation ppp
Router B#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router B (config)#interface serial 4/0
Router B (config-if)#encapsulation ppp
验证广域网接口的封装类型：
Router A#show interfaces serial 4/0
Index(dec):1 (hex):1
serial 4/0 is UP , line protocol is UP
Hardware is Infineon DSCC4 PEB20534 H-10 serial
Interface address is: 172.16.2.1/24
MTU 1500 bytes, BW 2000 Kbit
Encapsulation protocol is PPP, loopback not set
Keepalive interval is 10 sec , set
Carrier delay is 2 sec
RXload is 1 ,Txload is 1
LCP Open
Open: ipcp
Queueing strategy: WFQ
11421118 carrier transitions
V35 DCE cable
DCD=up DSR=up DTR=up RTS=up CTS=up
5 minutes input rate 30 bits/sec, 0 packets/sec
5 minutes output rate 19 bits/sec, 0 packets/sec
123 packets input, 3638 bytes, 0 no buffer, 28 dropped
Received 68 broadcasts, 0 runts, 0 giants
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 abort
89 packets output, 2312 bytes, 0 underruns , 0 dropped
0 output errors, 0 collisions, 7 interface resets
【注意事项】
封装广域网协议时，要求V.35线缆的两个端口封装协议一致，否则无法建立链路。