interface FastEthernet0/1
 ip address 10.1.1.1 255.255.255.0
 ip nat inside                 // 指定此接口位内部的网关, 并使用NAT共享内部用户访问INTERNET
 ip virtual-reassembly
 duplex auto
 speed auto
!
interface FastEthernet0/0
 no ip address
  ip virtual-reassembly
 duplex auto
 speed auto
 pppoe enable            //起用pppoe协议
 pppoe-client dial-pool-number 1        //dial-pool-number 1必须与dialer接口定义的dialer pool 一样
!
interface Dialer1
 mtu 1482
 ip address negotiated            //使用IP协商
 ip nat outside                      //定义NAT OUTSIDE接口
 ip virtual-reassembly
 encapsulation ppp
 dialer pool 1
 dialer-group 1
 ppp authentication pap callin
 ppp pap sent-username  username@dsl  password  88888888
!
!
ip route 0.0.0.0 0.0.0.0 Dialer1
!
ip nat inside source list 100 interface Dialer1 overload            //NAT配置
!
access-list 100 permit ip 172.16.1.0 0.0.0.255 any
dialer-list 1 protocol ip permit