thinQmaster Virtual testing partner Adaptive practice exams that find your weak spots and drill them. Every answer explained. From $69
Enroll

thinQmaster

Find your exam

Five questions free, before you decide.

Step 1 · choose a vendor

In one of our camps? Your practice exams come with the tuition — they are on your study page already.

Routing & Switching · Foundational

Link-State Routing Protocol

A routing protocol class where every router floods topology information and independently computes shortest paths with SPF.

Definition

Link-state routers flood link-state advertisements within an area so that each builds an identical link-state database. Each router then runs Dijkstra's shortest path first algorithm to compute a loop-free tree to every destination. OSPF and IS-IS are the main link-state IGPs; they converge quickly but require more memory and CPU than distance vector protocols.

Example

OSPF routers in area 0 share Type 1 and Type 2 LSAs to build the same LSDB.

Exam tip

Link-state protocols send triggered updates and periodic refreshes, not full periodic tables like RIP.

Related terms