Well… while some forms of Wireless Encryption will not stop this type of connection, there are others where you won’t be able to get a valid TCP/IP connection by just pretending to be the Mac Address.

On top of this, you are likely to require to make use of one of the many public DNS servers, as you likely won’t get any DHCP information passed onto you via connecting in this manner.

This is also assuming these wireless networks are making use of standard TCP/IP… as oppose to the many many other different network standards out there.

This is on top of wireless access points that don’t advertise, operate on randomised whitelists, are moving target access points (lots of security guard companies make use of these, oddly enough) — and don’t follow the standard expected policies and protocols that most wifi points work upon.

To set up these weird networks it is a simple matter of working with a DD-WRT modified router and/or a copy of FreeBSD with somewhat modified network hardware. It can be fun to see how you can make weird network set ups.

And yeah… there are networks that do make use of this silly stuff. And yeah — it can be subverted. However, one of the more common tactics for computer security is to make somebody else look like a better target.

Try various wireless setups… and then try breaking into your own wireless system