R5:
interface Virtual-Template1//C、进入模板就和配置PPP一样了，配置IP，和封装。
ip address 25.0.0.5 255.255.255.0
ppp authentication chap
!
interface Serial0//A、在接口封装FR,并且打开接口（no sh）
no ip address
encapsulation frame-relay
no frame-relay inverse-arp
!
interface Serial0.1 point-to-point//B、创建子接口，再启用一个模板
frame-relay interface-dlci 602 ppp Virtual-Template1
R2:
interface Virtual-Template1
ip address 25.0.0.2 255.255.255.0
ppp authentication chap
!
interface Serial0
no ip address
encapsulation frame-relay
no frame-relay inverse-arp
!
interface Serial0.1 point-to-point
frame-relay interface-dlci 206 ppp Virtual-Template1
!
=======================RIP AUTH==========================
R2:
key chain cisco//A、定义一个明文的key,
key 1
key-string cisco
interface Virtual-Template1
ip address 25.0.0.2 255.255.255.0
ip rip authentication key-chain cisco//调用key，完成rip的认证
ppp authentication chap
!
router rip //启动rip路由协议，version 2,(version 1 没有认证)
version 2
passive-interface Loopback0
network 2.0.0.0
network 25.0.0.0
neighbor 25.0.0.5
no auto-summary
R5:
key chain cisco
key 1
key-string cisco
interface Virtual-Template1
ip address 25.0.0.5 255.255.255.0
ip rip authentication key-chain cisco
ppp authentication chap
!
router rip
version 2
passive-interface Loopback0
network 5.0.0.0
network 25.0.0.0
neighbor 25.0.0.2
no auto-summary
