Originally Posted by x0r515t
I'm sure the network your describing is using MAC address filtering. You say your trying to connect to a wireless network of some kind, so most likely if this network really only allows certain computers to connect, the network is most likely filtering each machine by MAC address, which BTW is hardware specific not software.
MAC address filtering in wireless networks is actually more common than you would think, and certainly more secure than just encrypting your connection. Basically there is a database of allowed MACs and anything not in the database is not allowed to connect to the network.
This doesn't take into account separate wireless cards. For example, if you have a PowerBook or whatever, you can get a PCMCIA wireless card to access a wireless network. The card itself has the MAC address, so it wouldn't know if it was plugged into your PowerBook or any other laptop running any other OS. \MAC addresses are the same as IP addresses in terms of OS filtering: there is none.
In order for a network to filter by OS, it would have to ask the host what OS it is running. That isn't hard to do. Your computer would communicate this information to the network, and the network would decided whether to allow you or not. THE NETWORK CANNOT DETERMINE YOUR OS BY IP OR MAC ADDRESS.