This sample configuration bridges all protocols between two Cisco routers over a synchronous serial line. When a network is bridged instead of routed, both sites are part of the same logical network. To illustrate this, the above diagram includes some IP and IPX network numbers. However, the information is not necessary when configuring the router as a bridge.

The default encapsulation type used on leased lines between two Cisco routers is HDLC. However, when connecting to a non-Cisco router, PPP encapsulation must be used for third party compatability. This example also discusses how PPP encapsulation can be easily substituted in place of HDLC.

Note: The IP addresses included in this example are not necessary, but is encouraged to allow remote administration through telnet.

Before you begin

Get The IOS Leased Line Command Glossary. Faxback Doc #0553 Detailed descriptions of all IOS commands used in frame relay configurations. Also provides links to the IOS Command Reference if more information is required

Get The IOS Command Line Interface Tutorial Faxback Doc #ios_tutorial Instructions on configuring an IOS router using the command line interface

Note: Commands followed by a <*> are on by default and do not have to be configured. The "!" marks that appear in the configuration are automatically entered by the router and function as line separators for easier reading.

Atlanta Router Configuration
In IOS "show running-config" format

version 11.2 <*>
service udp-small-servers <*>
service tcp-small-servers <*>
!
hostname Atlanta
!
enable secret cisco
!
ip subnet-zero
no ip routing
no ip domain-lookup
!
interface Ethernet0
 ip address 10.1.1.1 255.0.0.0
 bridge-group 1
!
interface Serial0
 description Leased Line to Boston
 ip address 10.1.1.1 255.0.0.0
 ** add 'encapsulation ppp' to communicate with third party routers **
 bridge-group 1
!
ip http server
!
bridge 1 protocol ieee
!
line con 0
 password console
 login
line aux 0 <*>
line vty 0 4
 password telnet
 login <*>
!
end <*>

Boston Router Configuration
In IOS "show running-config" format

version 11.2 <*>
service udp-small-servers <*>
service tcp-small-servers <*>
!
hostname Boston
!
enable secret cisco
!
ip subnet-zero
no ip routing
no ip domain-lookup
!
interface Ethernet0
 ip address 10.2.2.2 255.0.0.0
 bridge-group 1
!
interface Serial0
 description Leased Line to Boston
 ip address 10.2.2.2 255.0.0.0
 bridge-group 1
!
ip http server
!
bridge 1 protocol ieee
!
line con 0
 password console
 login
line aux 0 <*>
line vty 0 4
 password telnet
 login <*>
!
end <*>

After You've Tried

You've tried the configuration and it doesn't work. Help is available!

Get IOS Router Leased Line Troubleshooting Assistance Faxback Doc #ll_ts

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