<networking> (Or "MAC address") The physical address
identifying an individual Ethernet controller board. An
Ethernet addess is a 48-bit number aabbccddeeff where a-f are
hexadecimal digits. The first 24 bits, aabbcc, identify the
manufacturer of the controller. The Ethernet address is
hard-wired on some controllers, stored in a ROM on some, and
others allow it to be changed from software. It is usually
written as six hexadecimal numbers, e.g. 08:00:20:03:72:DC.
