JNCIA-Junos: Juniper Networks Certified Associate – Junos (2022) — Question 70

Which layer of the OSI model does a router use to make forwarding decisions?

Answer options

• A. Layer 3
• B. Layer 4
• C. Layer 5
• D. Layer 2

Correct answer: A

Explanation

The correct answer is A, Layer 3, because routers operate primarily at the network layer, where they make decisions based on IP addresses. Options B, C, and D refer to the transport, session, and data link layers respectively, which do not involve routing decisions.