Subject: Re: Changing MAC addresses?
To: David Woyciesjes <DAW@yalepress3.unipress.yale.edu>
From: Nathan J. Williams <nathanw@MIT.EDU>
List: port-alpha
Date: 06/15/2000 14:13:09
<DAW@yalepress3.unipress.yale.edu> (David Woyciesjes) writes:

> 	If I'm correct, MAC addresses are hardwired into the chips on any
> network interface. Part of the address identifies the manufacturer of the
> interface, and I'm not positive what the rest of the address is for. Type of
> a serial number (of sorts), I guess. So to replace them, you would need to
> reprogram one of the chips on the NIC itself.

It's not usually so bad. The much more common arrangement is that the
chip's address is programmable, the ethernet card or subsystem has
a EEPROM with the MAC address, and the driver reads the EEPROM and
writes to the chip. 

So, our drivers have the code to do this, but usually buried in part
of the chip attach or initialization code. It would be sort of neat if
the MAC-programming interface was exposed to higher layers by the
interface.

        - Nathan