ADSL Modem/Router configuration example on Cisco routers

Here is a sample of ADSL PPPOE and PPPOA configuration on Cisco routers :

PPPOA Link config :

interface ATM0
no ip address
no atm ilmi-keepalive
dsl operating-mode auto
!
interface ATM0.1
pvc 8/35
encapsulation aal5mux ppp dialer
dialer pool-member 1
!
interface Dialer0
description <description>
ip address negotiated
ip nat outside
encapsulation ppp
ip mtu 1452
ip tcp adjust-mss 1452
no ip route-cache
no ip mroute-cache
dialer pool 1
dialer-group 1
ppp authentication chap pap callin
ppp chap hostname <adsl username>
ppp chap password <adsl password>

!
dialer-list 1 protocol ip permit
!
ip nat inside source list 100 interface Dialer0 overload

PPPOE Link config :

interface ATM0
no ip address
no atm ilmi-keepalive
dsl operating-mode auto
!
interface ATM0.1
pvc 8/35
encapsulation aal5snap
pppoe-client dial-pool-number 1

!
interface Dialer0
description <description>
ip address negotiated
ip nat outside
encapsulation ppp
no ip route-cache
no ip mroute-cache
ip mtu 1452
ip tcp adjust-mss 1452
dialer pool 1
dialer-group 1
ppp authentication chap pap callin
ppp chap hostname <adsl username>
ppp chap password <adsl password>

!
dialer-list 1 protocol ip permit
!
ip nat inside source list 100 interface Dialer0 overload