How can I protect unauthorised access to my wireless and how can i find out if somebody is using it?

Question

its a netgear wireless device.

Answer 1

You have to do the following:

1) Configure your WiFi network not to broadcast its SSID.

2) Use WPA (or even better - WPA2) encryption. (Note - WEP encryption isn't good enough and can be easily cracked.)

3) Configure your WiFi router to allow connections only from devices with particular MAC addresses.

How exactly you would do the above depends on your WiFi router - check its documentation. And keep in mind that although the above would make your WiFi network pretty secure, it won't be bullet-proof. The SSID can be discovered, WPA can be cracked (it's just way more difficult than WEP), MAC addresses can be spoofed. It's just very difficult to do all these things, so an attacker is likely to move to a less well protected target.

Answer 2

first thing is first: DONT BROADCAST YOUR SSID. This will make you "invisible"

second, to see if any one is leeching off your connection, goto your router setup page from the web browser and look at the stats. You will see which clients are connected.

second layer of wireless security is a password.

Answer 3

installing firewall and other security issues
will fix your prob