Switch0、Switch1、Switch2和Switch3均为二层交换机。总部拥有的IP地址块为202.114.12.0/24。Switch0的端口e0/24与路由器R2的端口e0/0相连，请根据图17-25完成路由器R2及Switch0的配置。
R2(config)#interface fastethernet 0/0.1
R2(config-subif)#encapsulation dotlq (3)
R2(config-subif)#ip address 202.114.12.1 255.255.255.192
R2(config-subif)#no shutdown
R2(config-subif)#exit
R2(config)#interface fastethernet 0/0.2
R2(config-subif)#encapsulation dotlq (4)
R2(config-subif)#ip address 202.114.12.65 255.255.255.192
R2(config-subif)#no shutdown
R2(config-subif)#exit
R2(config)#interface fastethernet 0/0.3
R2(config-subif)#encapsulation dotlq (5)
R2(config-subif)#ip address 202.114.12.129 255.255.255.192
R2(config-subif)#no shutdown
R2(config-subif)#exit
R2(config)#interface fastether0/0
R2(config-if)#no shutdown
Switch0(config)#interface f0/24
Switch0(config-if)#switchport mode (6)
Switch0(config-if)#switchport trunk encapsulation (7)
Switch0(config-if)#switchport trunk allowed all
Switch0(config-if)#exit
