Re: Detecting MAC Spoofing/reading REAL MAC address

From: Barry Margolin (
Date: 07/22/03

Date: Tue, 22 Jul 2003 14:55:52 GMT

In article <>,
Jorge Muria <> wrote:
>I'm making a program that identifies various PC's in a network by
>their MAC addresses. I though that thay could not be changed but they
>can. It's as easy as changing the attributes in the ethernet
>configuration (Windows 2000/XP).
>Now that all my work is almost trash. I have the hope that there is a
>way to know the REAL-HARDWARE Mac address. Or at least if there is a
>way to know if a retreived MAC address is faked (copied from other


I think the usual solution to this is using a switch that detects when a
MAC address moves to a different port, and either raises an alarm or shuts
down the port.

Barry Margolin,
Level(3), Woburn, MA
Please DON'T copy followups to me -- I'll assume it wasn't posted to the group.

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