Ref: 09330024
Title: Token and Ethernet Numbers and IEEE 802 Node Addressing
Date:  10/22/87

Copyright 3Com Corporation, 1991.  All rights reserved.

Do 3Com Ethernet address numbers come from Xerox?   The same chip
is used for token boards.  Where do those unique numbers
originate?  Why does 3CCom have them on the token boards?  What
part does the number play in relation to the Tok.sys driver or
other software?

Answer:

Xerox went out of the numbers business 2 years ago.  The IEEE now
administers addresses. A company is given a block of addresses to
be used on any IEEE 802 network.  There is no possibility of
duplicate addresses unless someone uses addresses that have not
been assigned to them.

3Com has 02608C000000H through 02608CFFFFFFH.  Each prom we burn
has a different address, but all must be within this range. We
use this same block of addresses for stations, servers, and
adapters. This address is used as the "station address", and the
adapter will receive frames only where the source address in the
frame matches the address in the address prom. To receive
packets, you need an address. The only exception is broadcast
packets, which go to all nodes. We can also use this address to
identify the hardware as 3Com-manufactured.
