MAC address

The MAC address, or Media Access Control address, (sometimes Physical address) is a unique identifier assigned to network adapters and network interface cards (NICs) by the manufacturer of the hardware. This address can be queried by users on the network the card is connected to. It is a permanent assignment to the network card, unlike an IP address which is assigned on a per-connection basis.

Windows

On Windows, you may query your own MAC addresses by running cmd and typing ipconfig /all. It will be a string of 6 2-digit hex numbers under each network device. Alternately, navigate to network connections> your device name >Status>Support>Details.

Linux

ifconfig -a typically works. Otherwise, shout loudly into the built-in mic until it succumbs to your will.

Macintosh

Use ifconfig in the terminal window. It should be the only hex address under en0. Alternately, go to Apple>About This Mac>Network>your device name>and look under Ethernet: MAC Address

It should be known that it is possible to change the appearance of the MAC address of a network device through MAC Spoofing

The IEEE, which distributes addresses to manufacturers, also has built in addresses to interact with multiple NICs at once:

• Packets sent to broadcast addresses are received by all points on a LAN.
• Packets sent to multicast addresses are received by all points on a LAN that are configured to receive that specific reserved multicast address.