Neighbor Authentication
As with other protocols, we can force BGP to authenticate other routers with a password. All passwords are scrambled using an MD5 message digest. On the network in Figure 10-1, we can enable password authentication between office-r1 and office-r2 by adding the password command to our BGP configuration. On office-r1, we add the neighbor...password command after the neighbor...remote-as command. You must configure the same password on both routers, or they can't communicate with BGP. Here's the configuration for office-r1:
router bgp 3000 neighbor 192.168.3.2 remote-as 3000 neighbor 192.168.3.2 password letmein
The same goes for office-r2:
router bgp 3000 neighbor 192.168.3.1 remote-as 3000 neighbor 192.168.3.1 password letmein