Simulating Simple BGP

Practical 4: Simulating Simple BGP
Advance Computer Network MSc IT Part 1 Practicals

Network Topology

Configuring IP addresses on all the interfaces
Router R1

Router(config)#int f1/0
Router(config-if)#ip add 192.168.0.2 255.255.255.0
Router(config-if)#no shut
Router(config-if)#exit
Router(config)#

Router R2

R2(config)#int f1/0
R2(config-if)#ip add 192.168.0.1 255.255.255.0
R2(config-if)#no shut
R2(config-if)#exit
R2(config)#int f1/1
R2(config-if)#ip add 10.0.0.1 255.255.255.0
R2(config-if)#no shut
R2(config-if)#exit
R2(config)#

Router R3

Router#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#int f1/0
Router(config-if)#ip add 10.0.0.2 255.255.255.0
Router(config-if)#no shut
Router(config-if)#exit
Router(config)#int f1/1
Router(config-if)#ip add 192.168.100.1 255.255.255.0
Router(config-if)#no shut
Router(config-if)#exit
Router(config)#

Router R4

Router>en
Router#conf t
Enter configuration commands, one per line.  End with CNTL/Z.
Router(config)#int f1/0
Router(config-if)#ip add 192.168.100.2 255.255.255.0
Router(config-if)#no shut
Router(config-if)#exit

Configuring BGP between R1 and R2 on AS1
On Router R1

Router(config)#router bgp 1
Router(config-router)#neighbor 192.168.0.1 remote-as 1
Router(config-router)#exit
Router(config)#

On Router R2

R2(config-router)#exit
R2(config)#router bgp 1
R2(config-router)#neighbor 192.168.0.2 remote-as 1
R2(config-router)#neighbor 192.168.0.2 next-hop
R2(config-router)#neighbor 192.168.0.2 next-hop-self

Configuring BGP between R2 and R3 on AS1 and AS2 respectively
On Router R2

R2(config)#router bgp 1
R2(config-router)#network 192.168.0.0 mask 255.255.255.0
R2(config-router)#neighbor 10.0.0.2 remote-as 2
R2(config-router)#exit
R2(config)#

On Router R3

Router(config)#router bgp 2
Router(config-router)#neighbor 10.0.0.1 remote-as 1
Router(config-router)#network 192.168.100.0 mask 255.255.255.0
Router(config-router)#

Configuring BGP between R3 and R4 on AS2
On Router R3

Router(config)#router bgp 2
Router(config-router)#neighbor 192.168.100.2 remote-as 2
Router(config-router)#neighbor 192.168.100.2 next-hop-self
Router(config-router)#

On router R4

R4(config)#router bgp 2
R4(config-router)#neighbor 192.168.100.1 remote-as 2
R4(config-router)#exit
R4(config)#

Verifying the network
R2

R2#show ip bgp
R2#show ip bgp summary

On R1

We could successfully reach to router R4 on AS2
On R3

R3#show ip bgp neighbors

On R4
We ping router R1 on AS 1