DR BDR election
CCNA
OSPF Passive Interfaces: Configuration and Best Practices
In OSPF (Open Shortest Path First), a passive interface is an interface on which the router stops sending OSPF Hello packets, while still advertising that interface’s connected network in OSPF. Because no Hellos are sent, no OSPF neighbor adjacency can form on that link — but the subnet remains reachable and advertised to the rest...
CCNA
Link-State Routing Protocols Explained: Discovery, Flooding, and the SPF Tree
Link-state routing protocols are also known as shortest-path-first protocols. Every router running one maintains a complete picture of the entire network topology, built by having each router originate information about itself, its directly connected links, and the state of those links — then flooding that information to every other router in the area. OSPF is...