If you set up a wireless network on your laptop, you need to make it secure. You don’t want anyone within reach of your wireless signal to be able to use the network, or worse, eavesdrop on the electronic information that passes between devices. Even worse: If you’ve enabled “sharing” of files or folders, an outsider who gets through the electronic front door may be able to get into the data on the disks of any machine on the network.

The most commonly offered security options follow:

  • Wired Equivalency Privacy (WEP). To sign on to a network that uses WEP, you need to know the WEP key, usually a numerical password. Most routers offer a choice between 64-bit and 128-bit encryption. WEP 64-bit codes are ten digits or letters in length, while more secure 128-bit numbers require 26 digits. Follow the instructions offered by the router maker to enter and verify a key.

  • WiFi Protected Access (WPA). A newer and more robust form of security, WPA is considered by many experts to be an improvement on WEP. WPA2, the latest implementation, is included with Windows Vista and Windows XP with Service Pack 2 installed.

  • Media Access Control (MAC). This system functions as if you were issuing keys only to a specified and pre-identified group of users. A router based on MAC does not use a password to authenticate users but instead compares the address it finds within each computer’s network interface card to see if it is on the authorized list of users for your network. If you add a new machine or want to grant a visitor access to your network you will have to sign on to the configuration screen of your router and add a new MAC address to the list.