Lesson Plan

• Describe the function of a Network Interface Card (NIC) in a computer network.
• Explain how MAC addresses uniquely identify NICs and support frame delivery.
• Compare the roles of MAC and IP addresses and identify common misconceptions.
• Demonstrate how switches use MAC addresses to forward frames.
• Evaluate the impact of NIC features (e.g., offloading) on system performance.

• Projector and screen
• Printed handout with NIC diagram and MAC address table
• Ethernet cables and a USB‑NIC adapter for demo
• Network switch (or simulation software)
• Worksheet for MAC‑address framing activity
• Exit‑ticket cards

Begin with a quick scenario: “If you sent a letter without a postal address, would it ever reach its destination?” Connect this to why computers need a physical address. Recall that students already know basic network concepts such as cables and IP addresses. State that by the end of the lesson they will be able to identify the role of NICs and MAC addresses in successful communication.

1. Do‑now (5'): Short quiz on the difference between IP and MAC addresses.
2. Mini‑lecture (10'): Explain NIC functions, OSI layers, and MAC address format using slides.
3. Live demo (10'): Show a physical NIC, display its MAC address via command line, and point out built‑in vs. external adapters.
4. Guided activity (15'): In pairs, students complete a MAC address table and map frame flow on a LAN diagram.
5. Switch simulation (10'): Use an online tool to illustrate how a switch forwards frames based on destination MAC.
6. Check for understanding (5'): Exit‑ticket question – “Why can a switch forward a frame without knowing the IP address?”

Summarise that NICs provide the physical link and unique MAC addresses that enable switches to direct traffic efficiently. Collect exit‑ticket responses to gauge understanding, and assign a brief homework: research one method of MAC address spoofing and its security implications.