OSPF

What is RIP (Routing Information Protocol)?

RIP (Routing Information Protocol) is one of the oldest distance-vector routing protocols, used by routers to share reachability information within an autonomo…

What is OSPF (Open Shortest Path First)?

OSPF is a link-state interior gateway routing protocol that lets routers within a single autonomous system share their local link information with every other…

What is a Router Routing Table?

A routing table is the data structure a router consults for every packet it forwards, listing known destination networks alongside the next-hop address and out…

Static vs Dynamic Routing: What is the Difference?

Static routing means an administrator manually configures fixed routes in a router’s routing table, while dynamic routing means routers automatically discover…

What is Route Summarization?

Route summarization (route aggregation) is the practice of combining multiple contiguous IP subnet routes into a single, shorter-prefix route so that routers a…

What is Administrative Distance?

Administrative distance (AD) is a per-protocol trust rating, typically 0-255, that a router uses to decide which source to believe when it learns a route to th…

Distance-Vector vs Link-State Routing

Distance-vector routing (e.g., RIP) has each router share its entire routing table with only its direct neighbors and pick paths based on hop count or a simple…

What is Equal-Cost Multipath (ECMP)?

Equal-Cost Multipath (ECMP) is a routing technique where a router installs and actively uses multiple paths to the same destination in its forwarding table sim…

What is a Routing Loop?

A routing loop is a condition where two or more routers each believe the best path to a destination is through the other, so a packet keeps bouncing between th…