In order for computers connected to a network to exchange information directly, they must be somehow identified. An IP address (dynamic or permanent) and a MAC address serve this purpose, regardless of whether the computer is connected to the network.
What is MAC address
A MAC address is an alphanumeric code written in hexadecimal form that is assigned to any piece of network equipment by the manufacturer. Since each MAC address is unique, it is convenient to use it to identify a computer on a network. This cipher is stored in a ROM chip built into the network device.
Address ranges are allocated between manufacturers by the international association IEEE (Institute of Electrical and Electronic Engineers). By the first three bytes of the MAC address, you can find out the manufacturer, the rest of the digits determine the personal serial number assigned to this network device.
The MAC address is 48 bits long, which allows the use of 2 to the 48th power combinations of numbers and letters. This ensures that the code is unique for each device.
How to find the MAC address
Usually the MAC address is indicated on a sticker on the network device, but you can also find it out using standard operating system tools. On computers running any version of Windows, press Win + R and type cmd at the Open prompt. In the command window, type ipconfig / all. A list of all network devices installed on the computer appears, with a description of each of them. The "Description" line contains the name of the equipment, the "Physical address" line contains its MAC address. For example, if you connect to the Internet via Wi-Fi, then in the Ethernet adapter section you will see the MAC address of the network card, and in the Wireless LAN adapter section - the MAC address of the Wi-Fi adapter.
How to change the MAC address
Sometimes you need to change the MAC address, for example, if the provider's services are tied to it, and you have changed your laptop or network card. Use the Win + R keys to bring up the Open dialog box and enter the ncpa.cpl command. The "Network Connections" window will open. Right-click on the desired connection icon and select Properties. Next to the name of the network device, click "Configure" and go to the "Advanced" tab. In the list on the left, find the "Network Address" parameter and enter the desired MAC address value in the "Value" line on the right. Click OK to confirm.
Remember to check with the ipconfig / all command to see if the MAC address has changed.
You can open the network connections window using the taskbar. If you have Windows XP, double-click on the "Network Connections" icon, if Windows 7, in the Control Panel, open the "Network and Internet" section and click on the "Network Control Center" icon. In the new section, follow the link "Change adapter settings" and in the "Status" window, click the "Properties" button. In the new window, click "Configure" and proceed as described above.