拓扑:
CCNA:PPP协议PAP和CHAP认证实验_休闲 
配置步骤:
RA
en
conf t
ho RA                           <<更改主机名
no ip domain-lo                   <<禁用DNS 
lin c 0                            
logg s                           <<显示同步
exec-t 0 0                        <<配置超时
exit
in s0/0
ip ad 192.168.1.1 255.255.255.0      <<配置IP地址掩码
encapsulation ppp                  <<封装协议为PPP
ppp authentication chap             <<启用CHAP认证
ppp chap hostname zsc              <<配置主认证方发出的认证用户名
no sh
exit
in s0/1
ip ad 192.168.1.2 255.255.255.0
encapsulation ppp
ppp authentication chap pap <<ppp混合认证,先采用CHAP认证,失败后采用PAP认证
ppp chap hostname zsc
no sh
exit
username td01 password 0 123       <<配置认证数据库(被认证方的主机名和密码)
username td02 password 0 456
exit
RB
en
conf t
ho RB
no ip domain-lo
lin c 0
logg s
exec-t 0 0
exit
 
in s0/0
ip ad 192.168.1.3 255.255.255.0
encapsulation ppp
ppp chap hostname td01             <<配置本机主机名
no sh
exit
username zsc password 0 123  <<配置认证用户名和密码(发送主认证方用户名和本机密码)
exit
RC
en
conf t
ho RC
no ip domain-lo
lin c 0
logg s
exec-t 0 0
exit
 
in s0/1
ip ad 192.168.1.4 255.255.255.0
encapsulation ppp
ppp chap hostname td02
no sh
exit
username zsc password 0 456
exit