Which of the following descriptions about Layer 2 switches is correct?

Question

Options

• AData can only be received or sent at any time
• BEach interface has a unique MAC address
• CSupport packet forwarding based on MAC address
• DSupport routing function

• A
  9% (3)
• B
  3% (1)
• C
  82% (27)
• D
  6% (2)

Explanation

Layer 2 switches operate at the Data Link layer of the OSI model and make forwarding decisions based on MAC addresses - they maintain a MAC address table (CAM table) mapping MAC addresses to switch ports, which is exactly what option C describes.

Why the distractors are wrong:

• A is incorrect because Layer 2 switches support full-duplex communication, meaning they can send and receive data simultaneously on the same interface - the opposite of what A states.
• B is incorrect because it's the ports/interfaces that learn and store the MAC addresses of connected devices; the switch itself has one MAC address for management purposes, but interfaces don't each have unique MACs in the way described.
• D is incorrect because routing (forwarding based on IP addresses) is a Layer 3 function, performed by routers or Layer 3 switches - a standard Layer 2 switch has no routing capability.

Memory tip: Think of the OSI layer number as your anchor - Layer 2 = MAC addresses (both have the "address" concept at the data link level), while Layer 3 = IP addresses and routing. If a question mentions routing, it's Layer 3; if it mentions MAC-based forwarding, it's Layer 2.

No community discussion yet for this question.