JNCIS-SP: Juniper Networks Certified Specialist – Service Provider Routing (2021) — Question 14

Which statement is true regarding default MPLS label handling?

Answer options

• A. A router that pops a label from a label stack always pushes a new label on the packet
• B. A router that pops a label from a label stack forwards a frame based on the label that was popped.
• C. A router that pops a label from a label stack forwards a frame based on the underlying destination IP address.
• D. A router that pops a label from a label stack applies class of service based on the IP header to ToS bits.

Correct answer: C

Explanation

The correct answer is C because when a router pops a label from the stack, it uses the destination IP address to make forwarding decisions. Options A and B are incorrect as they misrepresent the label handling process, and option D incorrectly states how class of service is determined.