在本节的实验中，将对PPP认证、DDR和Multilink进行配置，更深入地了解ISDN和拨号网络的配置技能。
1.实验目的
通过本实验，读者可以把握以下技能:
配置PPP CHAP认证;
配置dialer map;
配置DDR
配置Multilink;
查看和监测有关信息。
2.设备需求
本实验的设备需求与实验1完全相同，请参见实验1的相关内容。
3.拓扑结构及配置说明
本实验的拓扑结构如图7-2所示，R1和R2路由器分别连接1条ISDN BRI线路。
为达到配置DDR的目的，在R1和R2上分别创建1个回送接口(L0)。
各路由器BRI接口、L0接口的ip地址和所连接线路的ISDN号码见图7-2中的标注。
实验要求配置R1和R2，实现从10.1.1.0/24网段到10.1.2.0/24网段的连通，同时提供拨号连接的安全性，并使用相应命令实现R1和R2之间的128kbit/s的连接带宽。
4.实验配置及监测结果
实验中综合使用了DDR、PPP认证和PPP Multilink技术，让我们来看如何配置路由器以满足实验的要求。
配置清单7-2是R1和R2的具体配置。
配置清单7-2配置DDR、PPP认证和ppp Multilink
第1段：R1的配置清单
R1#sh run
Building configuration...
Current configuration : 2752 bytes
!
version 12.1
service timestamps debug uptime
service timestamps log uptime
no service passWord-encryption
!
hostname R1
username R2 password 0 cisco
!
ip subnet-zero
no ip domain-lookup
isdn switch-type basic-iietS
!
interface Loopback0
ip address 10.1.1.1255.255.255.0
interface BRIO
ip address 192.168.1.1255.255.255.0
encapsuSation ppp
dialer idle-timeout 300
dialer map ip 192.168.1.2 name R2 broadcast 80000002
dialer load-threshold 128
dialer-group 1
no cdp enable
ppp authentication chap
PPP multilink
!
ip classless
ip route 10.1.2.0 255.255.255.0 192.168.1.2
!
dialer-list 1 PRotocol ip permit
line con 0
transport input none
line aux 0
transport input all
line vty 0 4
login
!
end
第2段：R2的配置清单
R2#sh run
Building configuration...
Current configuration : 1086 bytes
!
version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
service udp-small-servers
service tcp-small-servers
!
hostname R2
!
useriiame R1 password 0 cisco
!
ip subnet-zero
no ip finger
!
isdn switch-type basic"net3
!
interface Loopback0
ip address 10.1.2.1255.255.255.0
!
interface BRIO
ip address 192.168.1.2 255.255.255.0
encapsiiSation ppp
dialer idle-timeout 300
dialer map ip 192.168.1.1 name Rl broadcast 80000001
dialer load-threshold 128
dialer-group 1
no cdp enable
ppp authentication chap
ppp multilink
!
ip classless
ip route 10.1.1.0 255.255.255.0 192.168.1.1
!
dialer-list 1 protocol ip permit
!
line con 0
transport input none
line aux 0
transport input all
line vty 0 4
login
!
end
第3段：监测配置结果
R1#debug ppp authentication
PPP authentication debugging is on
R1#ping 10.1.2.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.2.1, timeout is 2 seconds:
03:17:15: %LINK-3-UPDOWN: Interface BRIO:1, changed state to up
03:17:15: BRO:1 PPP: Treating connection as a callout
03:17:15: %ISDN-6-CONNECT: Interface BRIO:1 is now connected to 80000002
03:17:17:BRIO:1 CHAP:O CHALLENGE id 5 len 23 from"R1"
03:17:17:BRIO:1 CHAP:I CHALLENGE id 2 len 23 from"R2"
03:17:17:BRIO:1 CHAP:O RESPONSE id 2 len 23 from"R1"
03:17:17:BRIO:1 CHAP:I SUCCESS id 2 len 4
03:17:17:BRIO:1 CHAP:I RESPONSE id 5 len 23 from"R2"
03:17:17:BRIO:1 CHAP:O SUCCESS id 5 len 4
Success rate is 60 percent (3/5), round-trip min/avg/max == 36/37/40 ms
03:17:18: %LINEPROTO-5-UPDOWN: Line protocol on Interface BRIO:1, changed state to up
R1#ping 10.1.2.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.2.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 36/36/40 ms
R1#sh dialer map
R1#debug isdn q921
ISDN Q921 packets debugging is on
03:22:38:ISDN BRO:RX
03:22:38:ISDN BRO:TX
03:22:38:ISDN BRO:RX
03:22:38:ISDN BRO:RX
03:22:48: ISDN BRO:TX- RRpsapi=O tei=66 nr=0
03:22:48: ISDN BRO: RX
03:22:48: ISDN BRO:TX- RRfsapi=0 tei=66 nr=0
03:22:48: ISDN BRO: RX
03:22:48: ISDN BRO: RX
03:22:48: ISDN BRO: RX
R1#debug isdn q931
ISDN Q931 packets debugging is on
R1#ping 10.1.2.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.2.1, timeout is 2 seconds:
03:24:33: ISDN BRO: TX - SETUP pd = 8 callref = 0x04
03:24:33:Bearer Capability i=0x8890
03:24:33:Channel ID i=0x83
03:24:33: ISDN BRO: RX
03:24:33:Channel ID i=0x89
03:24:33: ISDN BRO: RX
03:24:33: ISDNRX
03:24:33: %LINK-3-UPDOWN: Interface BRIO: 1, changed state to up
03:24:33: %ISDN-6-CONNECT: Interface BRIO:2 is now connected to 80000002
03:24:34: ISDN BRO: RX
03:24:34:Cause i=Ox829A-Non-selected user clearing
03:24:34: ISDN BRO: TX- RELEASE_COMP pd=8 callref=0x81
03:24:34: %ISDN-6-CONNECT: Interface BRIO: 1 is now connected to 80000002
03:24:34: ISDN BRO: RX
Success rate is 60 percent (3/5), round-trip min/avg/max == 36/38/40 ms
R1#
03:24:37: %LINEPROTO-5-UPDOWN: Line protocol on Interface BRIO: 1, changed state to up
03:24:38: ISDN BRO: TX - SETUP pd == 8 callref = 0x05
03:24:38:Bearer Capability i=0x8890
03:24:38:Channel ID i=0x83
R2#ping 10.1.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.1.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 40/114/412 ms
我们采用把R1和R2的同类配置同时列出并讲解的方法，以方便读者更好地理解配置。实验1中己经配置过的项目不再是我们讲解的重点。
(1)配置用户名和口令。
R1:USernam R2 password 0 Cisco
R2:USemame R1 password 0 cisco
在R1上定义的用户名为R2，即拨号链路对端路由器名(由hostname所
