Re: MAC address change
On Sun, Jun 22, 2003 at 01:54:33PM +0200, Adam ENDRODI wrote:
> How widely do you think changing the MAC address of a NIC via
> ``ifconfig <if> hw'' is supported by the various network cards
> and drivers out there nowadays?
My experience is that everything I've tried it with has worked;
certainly Intel EtherExpress Pro 100s, Realtek based cards & DLink
via-rhine based cards. I suspect the number of cards that can do this
vastly outnumber the number of cards which can't these days.
> My collegue and me have debated several times whether watching
> the LAN for non-matching IP-MAC pairs can reveal any useful
> information. I argued that it may not, since the MAC is easily
> alterable, but he objected, because it's not. Now I ask you to
> decide who is right.
If you have a decent switch connecting the lan up you can lock each port
to a mac address (or several), which helps. Also even if you don't I'd
be surprised if everyone trying to use the network sat and watched for
MAC addresses and IP addresses and then chose a matching pair; more
likely they'd look for a gap in the IP addresses and choose one that
hadn't been used and so wouldn't know the MAC address. It's not perfect,
but it certainly /could/ reveal some useful information even if all
cards allow setting the MAC address.
J.
--
Jealousy strikes again.
Reply to: