BGP policy support conforms to which routing paradigm?

• A. Hop-by-hop routing
• B. Source routing
• C. Network flooding
• D. Destination routing

Answer: (A)

BGP policy support follows a hop-by-hop routing approach. In inter-domain routing, each border router within an autonomous system applies local policies and uses BGP attributes (like AS_PATH, next-hop, local preference, and MED) to select the best path and advertise it to its peers. Traffic is forwarded step by step from one hop to the next, with every router making its own forwarding decision based on its policies. This contrasts with source routing, where the entire path would be encoded and determined at the source, or with network flooding or a destination-centric approach. The distributed, per-hop decision process is what makes hop-by-hop routing the correct paradigm for BGP policy support.