What is a recommended practice for MD5 key management in large multi-peer environments?

• A. Use a single shared key for all peers.
• B. Rotate per-peer keys regularly and manage centrally.
• C. Keys should never be rotated.
• D. MD5 is obsolete; ignore keys.

Answer: (B)

Managing MD5 authentication keys in large, multi-peer BGP environments hinges on using separate keys for each neighbor and keeping them fresh. Per-peer keys tightly limit the blast radius if one key is exposed or a peer is compromised, because only that specific session is affected. Regularly rotating those keys reduces the window of opportunity for an attacker and makes revocation straightforward, since you can update or remove a single neighbor’s key without touching others. Centralized management supports automation, consistent policy enforcement, auditing, and clear change control, so rotations and key rollouts are scalable as the network grows. Using a single shared key across all peers introduces a single point of failure and is difficult to rotate safely at scale, while ignoring key management or treating MD5 as obsolete undermines the security of BGP session authentication.