Compare OSPF and BGP routing protocols.

OSPF (Open Shortest Path First): Interior Gateway Protocol for routing within an autonomous system (AS). Uses link-state algorithm, Dijkstra's shortest path. Converges quickly, hierarchical with areas, metric based on bandwidth. BGP (Border Gateway Protocol): Exterior Gateway Protocol for routing between ASs (internet backbone). Uses path-vector algorithm, policy-based routing. Slow convergence, focuses on reachability and policy. OSPF for internal networks, BGP for internet routing.