locking a wifi..

please help me how to lock my wifi connection because there are many outsiders using my wifi...please...my modem is router is prolink...and my OS is vista..

Set up WPA2 security:

http://www.computerworld.com/s/artic...eless_network_

http://www.google.com/#hl=en&site=&q...w=1112&bih=779

Also, for complete WiFi security, make sure that the main router login has a strong password on it. For the Wireless settings, make sure that you use WPA2 as the encryption algorithm. Then for absolute uncrackable security, create a password with a length of at least 12 characters, comprising a random mixture of upper case, lower case, numeric and symbol characters. That will give a bit entropy of >80 bits, which is currently considered uncrackable.

http://en.wikipedia.org/wiki/Password_strength

passwordmeter.com

Microsoft's Password Checker

thank you for the great help guys...:D