The Media Access Control (MAC) Address is used to uniquely identify a network device. Routers and other devices may have the capability to "clone" the MAC address of another device. For example, if your Internet Service Provider (ISP) has registered the MAC address of your computer on their network and will only provide service to the registered MAC address, cloning your computer MAC address to your router, avoids the need to reregister with your ISP.
A MAC address is in the form
hh:hh:hh:hh:hh:hh, where hh is a pair of hexidecimal
(base 16) numbers. Hexidecimal digits are
The Windows command line programs
(depending on your Windows version) will write a lot information about the installed network
adapters to the screen.
Physical Address is the MAC address.
Newer versions of Windows (2000 and up) have
getmac.exe program that returns the MAC
address of remote computers. Type
getmac /? for more information. This will return
information about a remote computer:
getmac /s mydomain.com
getmac /s 0.0.0.0
(where 0.0.0.0 is the IP address)
The Linux command line program
ifconfig.exe writes a lot information about the
installed network adapters to the screen. The number following
HWaddr is the MAC address.