MAC address: what is it and why is it needed?

MAC address: what is it?

Data exchange between devices operating in a global or local network is possible by assigning a specific address to each of them. In specialized literature, you can often find a definition of IP addresses, however, you also need to highlight the MAC address. What are its features? What functions does it perform?

General concept

Explanation of the abbreviation “MAC” – “Media Access Control”. It indicates the physical location of the network device, designated as a set of numeric and alphabetic characters. The most common writing format is “00-50-B6-5B-CA-6A”, however, other options are possible, with lowercase letters, which is typical for the CISCO company, separated by colons, used in operating systems on the Linux kernel. In the built-in memory of a computer or other device, such a number takes up 48 bits.

The MAC address can be compared to a passport. If you imagine a network as an apartment building, then the passport is the best identifier for a specific subscriber. The names and even surnames of residents can be repeated, but the passport is unique, allowing you to unambiguously identify the recipient or sender.

Parsing the structure

The numbers and letters in the MAC are not generated randomly, they depend on certain rules and requirements, due to which it is possible to encrypt important information in them. The structure can be divided into two parts:

• The first characters encode the manufacturer's code, which allows you to accurately determine who exactly made the device, be it a network card or a modem. For example, Google uses the combination “3C:5A:B4”, and the Chinese concern Huawei uses “00:9A:CD”.
• The following numbers and letters are an individual identifier. Random generation is allowed for this part; this is the algorithm used, for example, by Qualcomm and MediaTek.

To clarify the address of your device, study its structure, you can use both third-party applications and functions originally provided by the operating system. The first option is better suited for smartphones or tablets on Android, in Windows OS the necessary data can be obtained with the command “ipconfig”, and in Linux and Mac - “ifconfig”.

Classification

The MAC address is represented by two main categories:

• Local. Used to identify devices in small private networks, focused on internal rather than global use. A typical example is a home wireless Wi-Fi network, where the central link is a router to which smartphones, tablets, desktop computers, and laptops are connected.
• Global. In this case, the MAC address is assigned upon release of the device, must meet certain requirements and be unique throughout the Internet, which is necessary for error-free identification. The assignment of addresses is strictly controlled by an authorized organization, IEEE.

Functions

Knowledge of addresses greatly simplifies the collection of data about devices included in the network. Each of them is a personal identifier showing which equipment is active, how it interacts with other equipment, how it exchanges information. MAC addresses not only guarantee the accuracy of data exchange between devices, eliminate the risk of sending packets to the wrong recipient, help track traffic and reconfigure the network, but also solve many other problems:

• Increasing the level of network security. For example, for a wireless Wi-Fi router, you can set a “white list” of addresses. If the identifier of the device, be it a smartphone or a laptop, is not on this list, the connection will fail, the attempt will be automatically blocked.
• Simplifying network recovery. Software diagnostics will quickly determine the MAC address of equipment that has failed and needs to be repaired or replaced. This algorithm will help to carry out repairs as quickly as possible, eliminate the need for complex diagnostic operations, sequential testing of all hardware components.
• Configuring filters. It is not necessary to completely block certain addresses from accessing the network. You can limit yourself to more lenient restrictions, for example, on speed or access time. This will eliminate overloading of communication channels and other negative phenomena.

The MAC address can also become a valuable commercial tool. For example, in a cafe with a public Wi-Fi network, it becomes the basis for statistical reports, allows you to accurately record attendance, determine the busiest periods. Such statistics will help in determining the effectiveness of advertising campaigns, if the number of unique MACs after such campaigns has increased, the work was done correctly.

Author of the article:

Editor-in-Chief

Danaev Almaz