What is MAC Address?
MAC- Media Access Control is unique identifier that is assigned to network interface for communication at data link layer and is used as network address. It is often referred as a hardware or physical address. MAC’s are of 48-bit or 6 bytes and are written in MM:MM:MM:SS:SS:SS format. The first 3 bytes are ID number of manufacturer and next 3-bytes are serial number.
It represents Layer 2 of TCP/IP where IP represents layer 3. MAC address supports hardware implementation whereas IP address supports software implementation.
Where MAC is Stored?
MAC addresses are called the “burned in address”. NIC manufactures will assign MAC address to the device and hardcoded is stored in ROM chip and preloaded into non-volatile memory like EEPROM.
There are few USB adapters that are not having MAC address preloaded in firmware. These devices rely on software drivers that load on host system to assign the MAC.
So MAC can store on NIC or OS, depends on NIC design. The MAC address lives on the chip with the white sticker. But now you will find it on flash memory space on NIC or close to network hardware on a motherboard.
MAC is an important element of computer networking. It is an essential component that is required for protocols like TCP/IP to function. Changing MAC address also increase the privacy in some states. Though MAC addresses do not disclose any geographic or any information of ISP location such as IP addresses do.