MAC Address

In a Local Area Network (LAN), each device is identified by a MAC address.

Each Device Has Its Own MAC Address

Here, you can see three PCs connected to the same network.
Each of them has a different MAC address.

Figure 1 – Devices in a LAN identified by their MAC addresses

On each computer, there is at least one network interface, and each network interface has a unique MAC address.

You may be curious about MAC addresses. Their format may seem unusual.
There is a reason behind this design.

Let’s continue so you can learn more.

Let’s take the MAC address of PC1 as an example.

MAC Address Example

As you can see, a MAC address is made up of numbers and letters.

Figure 2 – MAC address Example

This format may look unusual at first, but it follows a precise structure designed to ensure uniqueness.
To understand why it is written this way, let’s take a closer look at how a MAC address is built.

MAC Address Structure

A MAC address is divided into two well-defined parts.

• Organizationally Unique Identifier (OUI)

• Network Interface Controller (NIC)

Figure 3 – MAC address structure with OUI and NIC