The MAC address is used for networking. It's encoded in the internet card on your PC. If you're on a network, the router has your MAC info in a table. Some networks are configured to only accept approved MAC addresses. This is not that useful for security anymore, now that software can crack a MAC address off an unencrypted wireless network in less than an hour.
Looking at my home network, I see that my firewall software knows the MAC address for the other PC's on my network. If that's true for a public network, I guess the MAC isn't designed to be kept secret.
There are probably cases and places where a faked MAC address could cause grief. However, since you can change it in WIndows, a system that uses it to track users isn't very secure. My internet company used to only allow PC's with registered MAC addresses to connect. I had to call up if I changed equipment. Now they don't care anymore. |