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。