Domain knowledge :
- Layer interface is configured for line connection point protocol encapsulation
- The PPP PAP and CHAP authentication, cpt support, do not have to do experiments on gns3.
- The factory default router is hdlc package ppp package is modified, chap PAP authentication or verification may be employed. pap is passed in clear text, two-way handshake, CHAP ciphertext verification is passed, three-way handshake.
Lab topology :
Key configuration :
PAP authentication : Password Authentication protocol, password authentication protocol.
Involved in the authentication router r1 and r2, r1 username and password pr2 r2, r1 and r2 username password pr1, authentication process, r1 and r1 transmitted pr1, pr2 r2 to r1 r2 and transmission to r2, thereby completing the authentication.
r1(config)#username r2 password pr2 #建立数据库保存对方的用户名和密码
r1(config)#inteface serial serial 0/0 #进入接口配置模式
r1(config-if)#encapsulation ppp #设置点点链路串口的二层封装为ppp协议
r1(config-if)#ppp authentication pap #设置ppp验证方式为pap（口令认证协议）
r1(config-if)#ppp pap setusername r1 password pr1 #设置发送的用户名和密码
r1(config-if)#no shutdown #开启接口
r2(config)#username r1 password pr1 #建立数据库保存对方的用户名和密码
r2(config)#inteface serial serial 0/0 #进入接口配置模式
r2(config-if)#encapsulation ppp #设置点点链路串口的二层封装为ppp协议
r2(config-if)#ppp authentication pap #设置ppp验证方式为pap（口令认证协议）
r2(config-if)#ppp pap setusername r2 password pr2 #设置发送的用户名和密码
r2(config-if)#no shutdown #开启接口- CHAP : Challenge Handshake Protocol, Challenge Handshake Authentication Protocol.
r3(config)#usename r4 password cisco #数据库中保存对方用户名和密码
r3(config)#interface serial 0/0 #进入接口配置模式
r3(config-if)#encapsulation ppp #采用ppp协议封装
r3(config-if)#ppp authentication chap #设置验证模式chap
r3(config-if)#no shutdown #开启接口
r4(config)#usename r3 password cisco #数据库中保存对方用户名和密码
r4(config)#interface serial 0/0
r4(config-if)#encapsulation ppp #采用ppp协议封装
r4(config-if)#ppp authentication chap #设置验证模式chap
r4(config-if)#no shutdown #开启接口