Understanding MAC Addresses: What They Are and How They Work

While IP addresses are used to identify devices on the internet, MAC addresses are used to identify devices on a local network. A MAC address is a unique identifier that is assigned to every network interface controller (NIC) in a device, including computers, smartphones, and printers. The acronym "MAC" stands for "Media Access Control," which refers to the process of controlling access to a network. When a device connects to a network, it sends a message called an "Address Resolution Protocol (ARP) request" to ask for the MAC address of the device it wants to communicate with. Once it has the MAC address, the device can send data to the other device on the network.

MAC addresses are unique and consist of six sets of hexadecimal characters. The first three sets are called the "Organizationally Unique Identifier (OUI)" and identify the manufacturer of the NIC. The last three sets are the "device identifier" and are assigned by the manufacturer. Unlike IP addresses, which can be changed or assigned dynamically, MAC addresses are hard-coded into the hardware of a device and cannot be changed. This makes them more reliable for network management and security purposes. MAC addresses are used in a variety of ways on local networks. For example, they can be used to limit access to a network by only allowing devices with certain MAC addresses to connect. They can also be used for network monitoring and troubleshooting by identifying the source of network traffic. However, it's important to note that MAC addresses are only used on local networks and are not visible to devices outside of the network. To communicate with devices on the internet, devices use their IP addresses. In conclusion, MAC addresses are unique identifiers that are assigned to every network interface controller (NIC) in a device. They are used to identify devices on a local network and are hard-coded into the hardware of a device, making them more reliable for network management and security purposes. While IP addresses are used to identify devices on the internet, MAC addresses are used on local networks for network access control, monitoring, and troubleshooting.