Like other routing protocols, EIGRP can be configured for authentication. RIPv2, EIGRP, OSPF, IS-IS, and BGP can each be configured to authenticate their routing information.
It is a good practice to authenticate transmitted routing information. Doing so ensures that routers only accept routing information from other routers that have been configured with the same password or authentication information.
Note: Authentication does not encrypt the EIGRP routing updates.