NEOCODE

Unicast Routing Protocols MCQs

1. RIP (Routing Information Protocol)

1. Which transport layer protocol does RIP use?

Correct Answer: b) UDP

Explanation:
RIP uses UDP port 520 for communication. It doesn't require the reliability of TCP as it sends periodic updates.

2. What is the default update interval in RIP?

Correct Answer: a) 30 seconds

Explanation:
RIP routers send their complete routing tables to neighbors every 30 seconds by default.

3. Which metric does RIP use to determine the best path?

Correct Answer: c) Hop count

Explanation:
RIP uses hop count as its sole metric, with a maximum of 15 hops (16 is considered unreachable).

4. What is the administrative distance of RIP?

Correct Answer: d) 120

Explanation:
RIP has an administrative distance of 120, which is higher than OSPF (110) and EIGRP (90).

5. Which version of RIP supports classless addressing (CIDR)?

Correct Answer: b) RIP v2

Explanation:
RIP version 2 added support for CIDR, VLSM, and includes subnet mask information in its updates.

2. OSPF (Open Shortest Path First)

6. Which transport protocol does OSPF use?

Correct Answer: c) IP (directly)

Explanation:
OSPF operates directly over IP (protocol 89) and doesn't use TCP or UDP for its operation.

7. What is the administrative distance of OSPF?

Correct Answer: c) 110

Explanation:
OSPF has an administrative distance of 110, making it more preferred than RIP (120) but less than EIGRP (90).

8. Which algorithm does OSPF use?

Correct Answer: b) Dijkstra's

Explanation:
OSPF uses Dijkstra's Shortest Path First (SPF) algorithm to calculate the shortest path to all destinations.

9. What is an OSPF "Area 0" called?

Correct Answer: b) Backbone Area

Explanation:
Area 0 is the backbone area in OSPF that connects all other areas and is required in multi-area OSPF designs.

10. Which multicast address does OSPF use for updates?

Correct Answer: a) 224.0.0.5

Explanation:
OSPF uses 224.0.0.5 (AllSPFRouters) for general OSPF messages and 224.0.0.6 for DR/BDR communication.

3. BGP (Border Gateway Protocol)

11. Which transport protocol does BGP use?

Correct Answer: a) TCP

Explanation:
BGP uses TCP port 179 for reliable communication between BGP peers, unlike most routing protocols.

12. What is BGP primarily used for?

Correct Answer: b) Inter-domain routing

Explanation:
BGP is the protocol of the Internet, used for routing between autonomous systems (ASes) operated by different organizations.

13. Which attribute does BGP use to select the best path?

Correct Answer: b) AS_PATH

Explanation:
The AS_PATH is a key BGP attribute that lists the autonomous systems a route has traversed, used to prevent loops and influence path selection.

14. What is the default administrative distance of BGP?

Correct Answer: a) 20

Explanation:
eBGP routes have an administrative distance of 20 (iBGP routes have 200), making them highly preferred.

15. Which type of BGP is used between different AS (Autonomous Systems)?

Correct Answer: b) eBGP

Explanation:
eBGP (External BGP) is used for peering between routers in different Autonomous Systems, while iBGP (Internal BGP) is used within the same AS.