Host A is communicating with Host B through a Layer 2 switch. What is the highest layer that the switch will inspect the traffic in this scenario?

A Layer 2 switch's fundamental function is to forward Ethernet frames based on their destination MAC addresses, which are Data Link layer (Layer 2) identifiers. While some switches may have limited Layer 3 awareness for features like IP Multicast snooping, their core operation and the highest layer consistently inspected for primary forwarding remain the Data Link layer.

A Layer 2 switch typically does not inspect traffic at the Transport layer (Layer 4) for its basic forwarding operations.

A Layer 2 switch does not inspect traffic at the Network layer (Layer 3) to make its primary forwarding decisions; that is the role of a router or Layer 3 switch.

A Layer 2 switch does not operate at the Session layer (Layer 5) or above.