Physical vs. Logical Addresses
The NIC manufacturer burns the physical address or MAC address into the network card during the manufacturing process.
The MAC address is usually represented by 12 hexadecimal numbers.
The type of Network and Transport protocols used by the devices on a network dictate the format of the logical address.
TCP/IP and IPX/SPX protocols are routable, meaning that they can be used for communication between network segments divided by a router or routers.