By configuring your router to allow only access to few users, you can acquire a little bit of security, but not enough, since your own AP is still open for snoops if one of your PCs are turned off. A lot of WiFi users do away with MAC filtering, since AP won't be able to connect on a non-listed address. A great alternative is the WEP, but it takes longer to crack the encryption code if it's 64bit and not 128. Another way is to use encrypted tunnels on your wireless links - but there's a caveat to this, as it can halt your network to a
slower data transfer time.
