[Scottish] What's up MAC?

Ian Drake, IT, CIR, SE Dunbartonshire scottish at mailman.lug.org.uk
Mon Mar 10 11:37:02 2003

This might be a wild shot, and I may e talking mince (I do, often) but it's
my understanding that the MAC address is read from the ROM on the card at
driver start-up, this is then held in memory by the OS and it's this memory
that is used as the actual MAC address. Theoretically changing this in
memory after the card had booted should allow you to spoof a MAC addy.

If I recall the location on win95 is something like -

And under Linux this can be done with the good old ifconfig program

ifconfig ethX hw 00DEADBEEF00

and again, in theory this should work with any card (yeap, even the ones you
already got).

The cards that advertise as having changeable MAC addresses have software
available that will allow you to change the ROM on the NIC to a new address,
this has the advantage of allowing the change to survive a reboot.



I theory there is no difference between theory and practise, in practise
there is.

-----Original Message-----
From: Colin McKinnon [mailto:colin@wew.co.uk]
Sent: 10 March 2003 09:53
To: scotlug
Subject: [Scottish] What's up MAC?

Anybody know which NICs have programmable MAC addresses? Preferably 
configurable  under Windows as well as Linux. Extra browny points will 
be awarded for cheapness ;)


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