Implementing Cisco Enterprise Advanced Routing and Services (ENARSI) — Question 515

How are LDP neighbors discovered?

Answer options

• A. Broadcasts hellos are sent to the 255.255.255.255 broadcast address.
• B. Multicast hellos are sent to the 224.0.0.2 group address.
• C. Unicast hellos are sent to directly connected neighbors IP addresses.
• D. Multicast hellos are sent to the 224.0.0.5 group address.

Correct answer: B

Explanation

The correct answer is B because LDP uses multicast hellos sent to the 224.0.0.2 group address for neighbor discovery. Option A is incorrect as LDP does not use the 255.255.255.255 address for discovery. Option C is wrong since unicast is not the method used for LDP neighbor discovery, and option D is also incorrect because 224.0.0.5 is not the address used for LDP hellos.