If you take only one step to protect your home or small office network, it should be this: Use encryption. Wi-Fi networks are incredibly convenient -- and incredibly easy to spy upon. All that data going out over the air among your PCs and between your PCs and the Internet can easily be snooped on by anyone nearby using simple, off-the-shelf software such as packet sniffers.
There are two encryption Wi-Fi standards --- Wireless Equivalent Protocol (WEP) and Wi-Fi Protected Access (WPA). Don't use WEP -- it's not nearly as safe as WPA. In fact, the biggest security breach in history was caused because a store owned by TJX Companies Inc. that used WEP, which allowed hackers to break in to the network.
Here are the steps for the Linksys WRT54GX4 and many other Linksys models:
- Go to the Setup screen and choose Wireless --> Wireless Security. In the Security Mode drop-down box, choose WPA/WPA2 Personal, then choose either WPA Personal or WPA2 Personal.WPA2 is a more secure method, but your hardware and software may not support it. Check your network adapter manufacturer's Web site to see if it supports WPA2 Personal. Windows Vista supports WPA2 Personal, but not all versions of Windows XP do.
- To see if your version of XP supports WPA2 Personal, select Control Panel --> Add or Remove Programs. If the Show Updates check box is not selected, check it. Scroll to the Windows XP - Software Updates section and look for Windows XP Hot fix KB893357. If it's not there, your version of Windows XP won't support WPA2 Personal. You can, however, go to the Microsoft updates site, and download KB 893357 to turn on WPA2 functionality.
If you're not sure if your hardware and software supports WPA2 Personal, use WPA Personal.
- From the Encryption Algorithms drop-down list, choose TKIP. In the Personal Key box, type a key between 8 and 63 characters in length. The longer it is and the more random the characters, the more secure it will be. Write down the key. You'll need to use this on each wireless PC on your network.
- Leave the Group Key Renewal row at 3600. Click Save Settings. That applies the key to your network. Now, only PCs that use WPA encryption and the key you just generated will be able to get onto your network.
Next, configure each wireless computer on your network to use WPA and the key you just generated. (Wired PCs don't need to be configured.)
For each Windows XP PC
- Click the wireless connection icon in the system tray, then click Properties, click the Wireless Network tab, highlight your network, click Properties, and then click the Association tab.
- In the Network Authentication drop-down box, select WPA-PSK. In the Data Encryption dialog box, choose TKIP.
- When you do that, the box that reads "The key is provided for me automatically" is checked. Uncheck this box. Enter your WPA key in the "Network key" box, and type it again in the "Confirm network key" box.
- Click OK and then OK again. Now the Windows XP PC can connect to your network using WPA encryption.