Routers utilizing OSPF use the ________________ to acquire neighbors and maintain link-state awareness.

• A. Update Protocol
• B. Hello Protocol
• C. Flooding Protocol
• D. Keep-Alive Protocol

Answer: (B)

In OSPF, discovering neighbors and keeping track of who’s on each link is done with Hello packets. Routers periodically send Hello messages on every OSPF-enabled interface to find potential neighbors, verify they can form an adjacency, and agree on parameters like timing and area information. If neighbors respond and match these settings, an adjacency is established and link-state information can be shared, enabling the SPF algorithm to build the network’s topology. Other terms don’t fit here because updates flood link-state information after neighbors are established, floods describe the spread of those updates, and there isn’t a separate keep-alive mechanism in this protocol.