Multiple choice

Which method is most effective in protecting the routing information that is propagated between routers on the network?

  1. Disable IP source routing.

  2. Configure passive interfaces.

  3. Configure routing protocol authentication.

  4. Secure administrative lines with Secure Shell.

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Routing protocol authentication (such as MD5 authentication for OSPF, EIGRP, or BGP) cryptographically verifies routing updates between routers, preventing unauthorized or malicious route injection. Disabling IP source routing and using SSH for administrative access are good security practices but don't protect routing information itself. Passive interfaces prevent routing updates on specified interfaces but don't authenticate the updates that are sent.