JNCIS-ENT: Juniper Networks Certified Specialist – Enterprise Routing and Switching (2025) — Question 35

Which three statements describe what happens when processing a frame for a switched packet? (Choose three.)

Answer options

• A. The ingress PFE performs the MAC address lookup.
• B. The frame enters the ingress port and is forwarded out all ports.
• C. The frame enters the ingress port and is processed by the ingress PFE.
• D. The ingress PFE sends the header information to the Routing Engine.
• E. The egress PFE forwards the packet out the egress port towards the destination.

Correct answer: A, C, D

Explanation

The correct answers, A, C, and D, accurately describe the process where the ingress PFE is responsible for the MAC address lookup, processes the frame upon its arrival at the ingress port, and communicates header information to the Routing Engine. Option B is incorrect because the frame is not forwarded out all ports but rather processed first. Option E is also incorrect as it relates to the egress PFE's role rather than the actions at the ingress stage.