R1的配置 :(config)#interface s1
(-if)#ip address 10.1.1.1 255.255.255.0
(-if)#no shutdown
(config)#interface loop 0
(-if)#ip address 1.1.1.1 255.255.255.0
(config)#router rip
(config-router)#network 10.0.0.0
(config-router)#network 1.0.0.0
R2的配置(config)#interface s0
(-if)#clock rate 64000
(-if)#ip address 10.1.1.2 255.255.255.0
(-if)#no shutdown
(config)#interface s1
(-if)#ip add 172.16.1.2 255.255.255.0
(-if)#no shutdown
(config)#interface loop 0
(-if)#ip add 2.2.2.2 255.255.255.0
(config)#router rip
(-router)#network 10.0.0.0
(-router)#network 172.16.0.0
(-router)#network 2.0.0.0
R3的配置:(config)#interface s0
(-if)#clock rate 64000
(-if)#ip address 172.16.1.3 255.255.255.0
(-if)#no shutdown
(config)#interface s1
(-if)#ip address 192.168.1.3 255.255.255.0
(-if)#no shutdown
(config)#interface loop 0
(-if)#ip address 3.3.3.3 255.255.255.0
(config)#ip route 0.0.0.0 0.0.0.0 s1
(config)#router rip
(-router)#network 172.16.0.0
(-router)#network 192.168.1.0
(-router)#network 3.0.0.0
(config)#ip default-network 172.16.0.0注:将缺省路由发布到R1，R2
R4的配置(config)#interface s0
(-if)#clock rate 64000
(-if)#ip address 192.168.1.4 255.255.255.0
(-if)#no shutdown
(-if)#ip add 4.4.4.4 255.255.255.0
(config)#ip route 0.0.0.0 0.0.0.0 s0
