All of the switches in the exhibit are AOS-CX switches.

To prevent rogue OSPF routers in the network shown in the exhibit, the preferred configuration on Switch-2 is to configure OSPF authentication on Lag 1 in MD5 mode. This setup enhances security by ensuring that only routers with the correct MD5 authentication credentials can participate in the OSPF routing process. This method protects the OSPF sessions against unauthorized devices that might attempt to introduce rogue routing information into the network.

1.OSPF Authentication: Implementing MD5 authentication on Lag 1 ensures that OSPF updates are secured with a cryptographic hash. This prevents unauthorized OSPF routers from establishing peering sessions and injecting potentially malicious routing information.

2.Secure Communication: MD5 authentication provides a higher level of security compared to simple password authentication, as it uses a more robust hashing algorithm.

3.Applicability: Lag 1 is the primary link between Switch-1 and Switch-2, and securing this link helps protect the integrity of the OSPF routing domain.