Network Basics -- What Is a Random MAC Address?

On the Wi-Fi settings page on your phone, you may find that the MAC address is labeled as random. What does a random MAC address mean? What are the impacts of it?

MAC addresses can be seen as IDs of devices which are unique. When making phones or other electronic devices, the manufacturer allocates a MAC address to each device. In the past, our phones have only the device MAC address. Therefore, when our phones try to connect to a network, our device MAC information will be obtained by others for them to track our phone sand to obtain other information stored in our phones.
The current phones now have a random MAC address in addition to the device MAC address. When connecting to the Wi-Fi, you can choose to use the device MAC address or the random MAC address.
If you use a random MAC address, the phone randomly generates a MAC address and uses the MAC address to connect to the Wi-Fi. Externally, others only see the random MAC address. If you switch to another Wi-Fi, the random MAC address changes accordingly, which improves the security of your phone. Random MAC addresses also have disadvantages. For example, the allowlist or blocklist you set on the router may be disabled after the MACaddress changes.