CISCO CCNA Exam – Q200

What two things will a router do when running a distance vector routing protocol? (Choose two.)

A. Send periodic updates regardless of topology changes.
B. Send entire routing table to all routers in the routing domain.
C. Use the shortest-path algorithm to the determine best path.
D. Update the routing table based on updates from their neighbors.
E. Maintain the topology of the entire network in its database.

Correct Answers: A, D

Explanation:
Distance means how far and Vector means in which direction. Distance Vector routing protocols pass periodic copies of routing table to neighbor routers and accumulate distance vectors. In distance vector routing protocols, routers discover the best path to destination from each neighbor. The routing updates proceed step by step from router to router.

CISCO CCNA Exam – Q184

Which characteristics are representatives of a link-state routing protocol? (Choose three.)

A. provides common view of entire topology
B. exchanges routing tables with neighbors
C. calculates shortest path
D. utilizes event-triggered updates
E. utilizes frequent periodic updates

Correct Answers: A, C, D

Explanation:
Each of routers running link-state routing protocol learns paths to all the destinations in its “area” so we can say although it is a bit unclear.
Link-state routing protocols generate routing updates only (not the whole routing table) when a change occurs in the network topology so Link-state routing protocol like OSPF uses Dijkstra algorithm to calculate the shortest path.
Unlike Distance vector routing protocol (which utilizes frequent periodic updates), link-state routing protocol utilizes event-triggered updates (only sends update when a change occurs).