Santos:CCNA Sec 210-260 OCG

Implement Routing Update Authentication on EIGRP

The addition of authentication to your routers’ EIGRP messages ensures that your routers accept routing messages only from other routers that know the same pre-shared key. Without this authentication configured, if someone introduces another router with different or conflicting route information on to the network, the routing tables on your routers could become corrupt and a denial-of-service attack could ensue. Thus, when you add authentication to the EIGRP messages sent between your routers, it prevents someone from purposely or accidentally adding another router to the network and causing a problem.

As with OSPF, MD5 authentication for EIGRP requires configuration at the interface level, that ...