A brief introduction to MAC addresses
MAC address, literally translated as media access control address, also known as LAN address, MAC address, Ethernet address or physical address, is an address used to confirm the location of network devices. In the OSI model, the third layer network layer is responsible for the IP address, and the second layer data link layer is responsible for the MAC address. MAC address is used to uniquely identify a network card in the network, and if a device has one or more network cards, each network card needs and will have a unique MAC address.
MAC addresses are produced by network equipment manufacturers and are flashed in the EPROM (a flash memory chip that can usually be erased by a program) on a network lnterface card. IP addresses and MAC addresses are represented in binary in computers, IP addresses are 32 bits, and MAC addresses are 48 bits.
The length of the MAC address is 48 bits (6 bytes), usually expressed as 12 decimal 16 numbers, such as: 00-16-EA-AE-3C-40 is a MAC address, where the first 3 bytes, the hexadecimal number 00-16-EA represents the number of the network hardware manufacturer, which is assigned by IEEE (Institute of Electrical and Electronics Engineers), and the last 3 bytes, the hexadecimal number AE-3C-40 represents the serial number of a network product (such as a network card) manufactured by the manufacturer. As long as you don't change your MAC address, the MAC address is unique in the world. Figuratively speaking, the MAC address is like the ID number on the ID card, which is unique.
How the MAC address is collected
In their daily work, friends will definitely encounter the scene of viewing the MAC address of the computer network card, and the following Xiaobian will tell you two common ways to collect/view MAC addresses.
1. Graphical interface collection
(1) In the lower right corner of the system window, select the network icon
(2) Right-click the network icon and click "Open Network and Internet Settings"
(3) Double-click "Network and Sharing Center"
(4) Click the network card of the connected network cable, as shown in the figure below, the status is "Connected".
If it is a wireless card, click "WLAN (wireless name)", as shown in the screenshot below
(5) In the pop-up Ethernet status window, click "Details"
(6) In the network connection details window, the 16-digit base number corresponding to the physical address is the MAC address that needs to be collected this time, as shown in the following figure. In this example, the MAC address is: EO-BE-03-5D-B9-40
2. Command line collection
1. Press the "Windows Window + R" key combination on the keyboard at the same time, (Note: the Windows Window key is located on the right side of the CTRL key), the system will pop up the "Run" window, then enter "cmd" and press the Enter key. As shown in the following figure
2. In the cmd command line window, enter ipconfig /all (this command can be directly copied and pasted), and pay attention to the following display content marked in red.
Where "Ethernet adapter" here represents the name of the network card. (If there are multiple network cards, such as notebooks that generally contain wireless and wired network cards, you need to distinguish, see step 4 for the way to distinguish.) Desktops typically have only one physical wired network card)
The physical address represents the physical address of the NIC, and a string of decimal numbers corresponding to its right needs to be collected. As shown in the figure below, the MAC address that needs to be collected this time is: EO-BE-03-5D-B9-40 (you can refer to the third step to copy the MAC address, no need to manually write it out)
3. Copy the MAC address. Choose one of the following two ways
(1) Select the MAC address and press "Ctrl+C" to copy it.
(2) Right-click on the white at the top of the CMD window, select "Edit", and then select "Copy"
4. Network card name identification (optional)
(1) In the lower right corner of the system window, select the network icon
(2) Right-click the network icon and click "Open Network and Internet Settings"
(3) Double-click "Network and Sharing Center"
(4) Find out that the name of the connected network port is consistent with the name output of the cmd command, which is the network card that needs to collect MAC addresses.
(5) If it is a wireless network card, refer to the following screenshot, which generally displays "WLAN (WiFi name)"