Implementing Cisco Enterprise Advanced Routing and Services (ENARSI) — Question 519

What is the function of penultimate hop popping?

Answer options

• A. The last P router in the path pops off the transport label before traffic is forwarded toward the PE.
• B. The VPN label is popped off at the egress LSR, and unlabeled traffic is forwarded toward the CE.
• C. The transport label is popped off at the egress LSR, and unlabeled traffic is forwarded toward the CE.
• D. The second to last P router in the path pops off the VPN label before traffic is forwarded to the last P router.

Correct answer: A

Explanation

The correct answer is A because penultimate hop popping occurs at the last P router, which removes the transport label before the traffic is sent to the PE. Options B and C incorrectly describe the egress LSR's role, while D misidentifies the router responsible for the VPN label removal.