MAC address (MAC, Media Access Control address) is a number that serves to identify the device within a computer network. MAC address is assigned by the manufacturer and is always unique.
How does the MAC address look like and what is it for?
It’s a number in hexadecimal that can look like this, for example: 00-48-4P-D5-3F-1A. It is assigned to every device connected to a Computer Network, such as laptop, computer, tablet, phone, and other Networking hardware, such as a router, wifi extender, switch, VoIP gateway, and so on. If a device is connected via cable as well as via wireless, each of these connections will have a different MAC address. This is because the MAC address is assigned to each network interface controller and in the situation previously described, you would have two of them - one controller for the cable connection and the other one for the wireless connection. Even when connected to a 2.4GHz (wifi n) and a 5 GHz (wifi ac) network, your machine will have two MAC addresses.
The MAC address serves as a unique identification of a computer (or other device on the network) and can be used, for example, to restrict access of unauthorized devices to a computer network. To do so, the network administrator configures the router to allow access only to a list of authorised MAC addresses. Other devices will not be able to connect. The MAC address serves uniquely for the internal operational purposes since the router is able to recognize the connected devices without sending their MAC addresses to the Internet.
A MAC address can be falsified or misused for the purpose of gaining access to wifi, for example.
Because the MAC address can be used to identify a particular device on the network (it is actually a network identifier), it can be considered personal data.
How can I find out a MAC address?
A common mistake is to confuse the MAC addresses of the cable and wifi connections (each with a different MAC address). There are various tools and commands that allow to find out the MAC address of your device.
How to find out the MAC address on Windows devices?
Run the command prompt (black window) in the Start menu using cmd command. In the open command prompt, type ipconfig/all.
How to find out the MAC address on Apple or Linux devices?
On Apple (MacOS, iOS) and Linux devices, launch the Terminal and enter the following commands: ifconfig and ip a.