Well, a MAC address is one way you can secure, for example, a WAP, or
Router, if the router supports it. It is the best security,  because it is
very difficult for someone to identify, and spoof a MAC address, although
such authorization is difficult to manage on large networks. If your
account is tied to a NIC MAC address, it would use that address, to
authorize access. But if you can connect with another NIC, then it isn't
the NIC MAC address that is authenticating . Maybe they mean the MAC
address of the modem?

Rode
The NOSPIN Group
http://www.freepctech.com/rode/


>My Comcast connection and account are (allegedly) tied to the MAC (Media
>Access Code) of my ethernet card. This is according to the Comcast
>Technical Support representatives with whom I spoke.(I say allegedly
>because, after an apparent failure of the ethernet card to which the cable
>modem was originally attached, I enabled the built-in ethernet connection
>of my motherboard and connected with that.) In any case, if the former
>owner's account is tied to the MAC of the device, is it possible that you
>are unable to connect for that reason?
>Paul A. Shippert

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