Example for MED BGP

R1,R2,R4 are in AS 100 and R4 is in AS 200. Consider R3 as office router having two connections to one ISP via R1 and R4. Below is the config for MED

R1
===========

!
interface Loopback1
 ip address 1.1.1.1 255.255.255.0
!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial1/0
 ip address 192.168.12.1 255.255.255.0
 serial restart-delay 0
 no fair-queue
!
interface Serial1/1
 ip address 192.168.14.1 255.255.255.0
 serial restart-delay 0
!
interface Serial1/2
 ip address 192.168.13.1 255.255.255.0
 serial restart-delay 0
!
interface Serial1/3
 no ip address
 shutdown
 serial restart-delay 0
!        
router bgp 100
 no synchronization
 bgp log-neighbor-changes
 network 1.1.1.0 mask 255.255.255.0
 neighbor 3.3.3.3 remote-as 200
 neighbor 3.3.3.3 ebgp-multihop 2
 neighbor 192.168.12.2 remote-as 100
 neighbor 192.168.14.2 remote-as 100
 no auto-summary
!
ip http server
!
ip route 3.3.3.3 255.255.255.255 192.168.13.2
!

R2
============

!
interface Loopback1
 ip address 2.2.2.2 255.255.255.0
!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial1/0
 ip address 192.168.12.2 255.255.255.0
 serial restart-delay 0
!
interface Serial1/1
 ip address 192.168.24.1 255.255.255.0
 serial restart-delay 0
!
interface Serial1/2
 no ip address
 shutdown
 serial restart-delay 0
!
interface Serial1/3
 no ip address
 shutdown
 serial restart-delay 0
!        
router bgp 100
 no synchronization
 bgp log-neighbor-changes
 network 2.2.2.0 mask 255.255.255.0
 neighbor 192.168.12.1 remote-as 100
 neighbor 192.168.24.2 remote-as 100
 no auto-summary
!

R4
=============


!
interface FastEthernet0/0
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface FastEthernet0/1
 no ip address
 shutdown
 duplex auto
 speed auto
!
interface Serial1/0
 ip address 192.168.14.2 255.255.255.0
 serial restart-delay 0
!
interface Serial1/1
 ip address 192.168.24.2 255.255.255.0
 serial restart-delay 0
!
interface Serial1/2
 ip address 192.168.34.1 255.255.255.0
 serial restart-delay 0
!
interface Serial1/3
 no ip address
 shutdown
 serial restart-delay 0
!
router bgp 100
 no synchronization
 bgp log-neighbor-changes
 neighbor 3.3.3.3 remote-as 200
 neighbor 3.3.3.3 ebgp-multihop 2
 neighbor 192.168.14.1 remote-as 100
 neighbor 192.168.24.1 remote-as 100
 no auto-summary
!
ip http server
!
ip route 3.3.3.3 255.255.255.255 192.168.34.2
!


R3
==========



!
!
interface Loopback1
 ip address 3.3.3.3 255.255.255.0
!
interface FastEthernet0/0
 ip address 10.10.10.1 255.255.255.0
 duplex auto
 speed auto
 no keepalive
!
interface FastEthernet0/1
 ip address 20.20.20.1 255.255.255.0
 duplex auto
 speed auto
 no keepalive
!
interface Serial1/0
 ip address 192.168.13.2 255.255.255.0
 serial restart-delay 0
!
interface Serial1/1
 ip address 192.168.34.2 255.255.255.0
 serial restart-delay 0
!
interface Serial1/2
 no ip address
 shutdown
 serial restart-delay 0
!
interface Serial1/3
 no ip address
 shutdown
 serial restart-delay 0
!        
router bgp 200
 no synchronization
 bgp log-neighbor-changes
 network 10.10.10.0 mask 255.255.255.0
 network 20.20.20.0 mask 255.255.255.0
 neighbor 192.168.13.1 remote-as 100
 neighbor 192.168.13.1 ebgp-multihop 2
 neighbor 192.168.13.1 update-source Loopback1
 neighbor 192.168.13.1 route-map forr2 out
 neighbor 192.168.34.1 remote-as 100
 neighbor 192.168.34.1 ebgp-multihop 2
 neighbor 192.168.34.1 update-source Loopback1
 no auto-summary
!
ip http server
!
!
!
access-list 1 permit 10.10.10.0 0.0.0.255
access-list 2 permit 20.20.20.0 0.0.0.255
!
route-map forf2 permit 20
!        
route-map forr1 permit 1
 match ip address 1
 set metric 200
!
route-map forr2 permit 20
 match ip address 2
 set metric 400
!