Implementing Cisco Enterprise Advanced Routing and Services (ENARSI) — Question 218

At which layer of the OSI model is an MPLS label imposed?

Answer options

• A. Layer 2
• B. Layer 3
• C. Between layers 2 and 3
• D. Between layers 3 and 4

Correct answer: C

Explanation

The correct answer is C because MPLS (Multiprotocol Label Switching) operates between Layer 2 (Data Link) and Layer 3 (Network) of the OSI model, effectively allowing it to encapsulate packets for efficient routing. Option A and B are incorrect as they refer to the individual layers where MPLS does not operate exclusively. Option D is also incorrect because MPLS occurs prior to Layer 4 (Transport).