What is a MAC address

The MAC address, also known as the physical (or hardware) address, is a unique identifier assigned to a computer's NIC (network interface card) and is stored in the hardware; the NIC helps connect the computer to other computers on the network. And the MAC address is unique for all NICs.

Format of MAC address

The number of MAC address is in hexadecimal Format is uniquely formatted as six groups of two numbers or characters, that is, 12 hexadecimal digits (48 bits or 6 bytes long) separated by hyphens (or semicolons). Examples of MAC addresses:

30-65-EC-6F-C4-58

MAC addresses are usually assigned by the hardware manufacturer, and these numbered IDs are seen burned into the firmware of the network access hardware. Therefore, some manufacturers (such as Dell) place a specific code called an Organizationally Unique Identifier (OUI) in the MAC address to identify the manufacturer. The OUIs of some well-known companies are:

Dell: 00-14-22

Cisco: 00-40-96

Nortel: 00-04-DC

Belkin: 00-30-BD

Note: Some companies may have multiple MAC addresses.

Note: The first 6 digits of the MAC address represent "OUI", and the last 6 digits are assigned by the manufacturer.

What does the MAC address do:

Because of the MAC The address is a unique address, so a computer network does not assign the same MAC address to multiple computers or network devices, all devices on the same network subnet have different MAC addresses. Let's take a look at the uses of MAC addresses:

1. It can be used in places where IP addresses change frequently. It can help network administrators obtain information about network traffic.

Because MAC addresses never change, this makes MAC addresses a more reliable way for network administrators to identify the sender and receiver of data on the network.

2. You can set filtering to only accept specific MAC addresses. This allows you to specify which computers can connect to our computer, prevent strangers from accessing the network (hackers and intruders), and filter potential junk. Email or virus attack;

3. Helps uniquely identify a computer from other computers around the world, and its geographical location can be found through MAC address lookup. This can be used to track network users and restrict their access, for example to identify when and where a stolen device connects to the network.

4. Can be used for data recovery.

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