The following configuration was used on a Cisco 837 Router to terminate an ADSL (PPPoA) connection in the UK. The configuration also shows examples of DHCP, NAT, Access Lists and Port Fowarding.

version 12.4
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname <Router Name>
!
boot-start-marker
boot-end-marker
!
enable secret 5 <Enable Password>
!
no aaa new-model
!
!
no ip dhcp use vrf connected
ip dhcp excluded-address 192.168.0.2 192.168.0.10
!
ip dhcp pool LAN
network 192.168.0.0 255.255.255.0
default-router 192.168.0.1
dns-server <DNS Server 1> <DNS Server 2>
!
!
ip cef
ip auth-proxy max-nodata-conns 3
ip admission max-nodata-conns 3
!
!
interface Ethernet0
ip address 192.168.0.1 255.255.255.0
ip nat inside
ip virtual-reassembly
ip tcp adjust-mss 1452
hold-queue 100 out
!
interface Ethernet2
no ip address
shutdown
hold-queue 100 out
!
interface ATM0
no ip address
no atm ilmi-keepalive
dsl operating-mode auto
pvc 0/38
encapsulation aal5mux ppp dialer
dialer pool-member 1
!
!
interface FastEthernet1
speed 100
full-duplex
!
interface FastEthernet2
shutdown
duplex auto
speed auto
!
interface FastEthernet3
shutdown
duplex auto
speed auto
!
interface FastEthernet4
shutdown
duplex auto
speed auto
!
interface Dialer0
description<ISP Name>ADSL
ip address negotiated
ip mtu 1492
ip nat outside
ip virtual-reassembly
encapsulation ppp
no ip route-cache cef
no ip route-cache
no ip mroute-cache
dialer pool 1
dialer-group 1
ppp authentication chap callin
ppp chap hostname <ISP Provided Hostname>
ppp chap password 7 <ISP Provided Password>
!
ip forward-protocol nd
ip route 0.0.0.0 0.0.0.0 Dialer0
!
no ip http server
no ip http secure-server
!
ip nat inside source list 100 interface Dialer0 overload
ip nat inside source static tcp 192.168.0.3 50001 interface Dialer0 50001
ip nat inside source static udp 192.168.0.3 50001 interface Dialer0 50001
!
access-list 1 permit any
access-list 100 permit ip 192.168.0.0 0.0.0.255 any
dialer-list 1 protocol ip permit
!
!
!
control-plane
!
!
line con 0
password 7 <Console Password>
login
no modem enable
line aux 0
line vty 0 4
password 7 <Telnet Password>
login
!
scheduler max-task-time 5000


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