Re: Silly NIC games ...
'The manufacturer gets alloted his "prefix", which is the first 24-bits of the address, then every card they make is then given a unique address using the prefix + a serial number from the manufacturer for the second 24-bits of the address'
It might also be possible to change the MAC in S/W.
I discovered that DECNET assumes the prefix will be DEC's own. We had installed DECNET emulator S/W for HP-UX. When we first fired it up it reset the HP server MAC to make it look like a DEC. There could have been a problem if it reset to another VAX on the network but you'd have to be very unlucky to have that happen. No we weren't unlucky like that. What did happen was that the change of MAC invalidated all the connected users' ARP caches. I can't remember how long it took but they did repopulate fairly quickly.