10 Distance Vector and Link-State Routing MCQ

 10 multiple-choice questions on Distance Vector and Link-State Routing with explanations, useful for UGC NET, SET, GATE, ISRO, and other competitive exams.

Question 1: Basic Concept of Distance Vector Routing

Q1: In a distance vector routing protocol, how do routers share routing information?

• A) By flooding the entire network with routing updates

• B) By periodically exchanging routing tables with their immediate neighbors

• C) By using a link-state database to determine the shortest path

• D) By dynamically updating paths based on link failure reports

Answer: B) By periodically exchanging routing tables with their immediate neighbors
Explanation: In Distance Vector Routing, routers share their routing tables with neighbors at regular intervals, leading to a simple but slow convergence mechanism.

Question 2: Example of Distance Vector Routing Protocol

Q2: Which of the following is an example of a Distance Vector routing protocol?

• A) OSPF

• B) RIP

• C) IS-IS

• D) BGP

Answer: B) RIP
Explanation: Routing Information Protocol (RIP) follows the Distance Vector approach, using hop count as its metric to determine the shortest path.

Question 3: Count to Infinity Problem

Q3: The "count to infinity" problem is associated with which type of routing protocol?

• A) Link-State

• B) Distance Vector

• C) Hybrid

• D) Static Routing

Answer: B) Distance Vector
Explanation: The count to infinity problem occurs in Distance Vector routing when routers continuously increase hop counts due to network changes, leading to slow convergence.

Question 4: Solution to Count to Infinity Problem

Q4: Which of the following is used to mitigate the "count to infinity" problem in Distance Vector Routing?

• A) Split Horizon

• B) Dijkstra’s Algorithm

• C) Link-State Advertisement

• D) Shortest Path Bridging

Answer: A) Split Horizon
Explanation: Split Horizon prevents routing loops by not advertising routes back to the router from which they were learned, reducing the risk of infinite loops.

Question 5: Link-State Routing Protocol

Q5: Which of the following is a Link-State routing protocol?

• A) RIP

• B) OSPF

• C) BGP

• D) IGRP

Answer: B) OSPF
Explanation: Open Shortest Path First (OSPF) is a Link-State protocol that builds a complete network topology using Link-State Advertisements (LSAs).

Question 6: Algorithm Used in Link-State Routing

Q6: Link-State Routing protocols primarily use which algorithm?

• A) Bellman-Ford Algorithm

• B) Dijkstra’s Algorithm

• C) Distance Vector Algorithm

• D) Greedy Algorithm

Answer: B) Dijkstra’s Algorithm
Explanation: Dijkstra’s Algorithm computes the shortest path from a source router to all destinations by maintaining a Link-State Database (LSDB).

Question 7: Routing Table Updates

Q7: How does a Link-State routing protocol update its routing table?

• A) By exchanging full routing tables periodically

• B) By sending incremental updates only when a topology change occurs

• C) By using static routes predefined by network administrators

• D) By relying solely on TCP connections

Answer: B) By sending incremental updates only when a topology change occurs
Explanation: Unlike Distance Vector protocols, Link-State protocols send updates only when network topology changes, reducing overhead and improving efficiency.

Question 8: Metric Used in OSPF

Q8: What metric does OSPF use to determine the best path?

• A) Hop count

• B) Bandwidth

• C) Cost

• D) Delay

Answer: C) Cost
Explanation: OSPF assigns cost to each link based on bandwidth, where higher bandwidth = lower cost, ensuring optimal path selection.

Question 9: Routing Protocol for Large Networks

Q9: Which routing protocol is most suitable for a large-scale enterprise network?

• A) RIP

• B) OSPF

• C) Distance Vector

• D) Static Routing

Answer: B) OSPF
Explanation: OSPF is scalable, supports hierarchical design using areas, and ensures faster convergence, making it ideal for large networks.

Question 10: Advantage of Link-State Over Distance Vector

Q10: Which of the following is a key advantage of Link-State routing over Distance Vector routing?

• A) Requires less memory

• B) Faster convergence

• C) Uses fewer control messages

• D) Uses hop count as a metric

Answer: B) Faster convergence
Explanation: Link-State protocols converge faster because routers maintain a full topology view, allowing immediate recalculations when a link fails.