Subject: Re:RE: Changing MAC addresses?
To: None <>
From: Erik Fair <>
List: port-alpha
Date: 06/15/2000 12:27:20
It's not just the DECnet that requires MAC address changes; so does 
the Xerox Network System (XNS), and its bastard son Netware (IPX). 
Since the original Ethernet standard was called "DIX" (DEC, Intel, 
Xerox), they specified the ability to program the MAC address for 
*all* Ethernet stations, while also setting up the world-wide unique, 
48-bit MAC address registry for Ethernet Interface manufacturers, now 
operated by the (damned) IEEE.

All Sun SPARCs use the same MAC address on all ethernet interfaces; 
they assume that they will have an Ethernet ("The Network is the 
Computer"!) and program a MAC address per motherboard, which the 
drivers then stuff into as many interfaces as they find. This 
assumes, of course, that each of these interfaces will be on a 
different network (think, L2 switches).

So, it is highly likely that der Mouse can do what he wants; the 
question is whether our drivers have that capability or not (and how 
it is exposed). If I'm not mistaken, there is something in the Sun 
ID-PROM FAQ (what to do about a dead one) about how to program the 
MAC interface from userland (though that might be firmware commands, 
rather than UNIX userland).

	Erik <>