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View Full Version : detecting a mac address before windows logs on



danielspencer2
07-01-2007, 04:26 AM
good morning all If i plugged a laptop into my router using an ethernet cable and turn that laptop on without logging it into windows xp, will the router still see the mac address of the laptop that is connected,even though windows xp has not been logged into?

Dannz
07-01-2007, 10:15 AM
Hi, Why do you now want the router to see your mac address?
Network interfaces (as far as i know) must have a mac address.

and yes, as its buit into the hardware, it will be able to see it.

bob_doe_nz
07-01-2007, 10:18 AM
Yes

Dannz
07-01-2007, 10:22 AM
Of course though, you can spoof a mac address.

danielspencer2
07-01-2007, 10:33 AM
r u sure that the router will pick up the mac address of the laptop's netword card even though the laptop will NOT be logged into windows xp? (the laptop will just be plugged into the router and turned on)



Hi, Why do you now want the router to see your mac address?
Network interfaces (as far as i know) must have a mac address.

and yes, as its buit into the hardware, it will be able to see it.

Dannz
07-01-2007, 10:34 AM
The mac address is built into the hardware, but windows xp will need to request an IP to annouce the mac, but ARP tables will have the mac in them.

TGoddard
07-01-2007, 11:37 AM
The network connection is not related to whether or not you are logged in. It will connect anyway. You can always change your card's MAC address at least temporarily, although I'm unsure of the procedure in Windows.

ughnz
07-01-2007, 05:33 PM
If the router or the network interface in the laptop can autosense the link speed and type then yes the mac address will be known without windows networking being active.

Also windows likes to send lots of crap to discover netbios name servers etc, unless you have turned that off. So as soon as any traffic is sent by the notebook then the MAC address will be known.