The Ultimate Wireless Guide

Use It

How to get the most from your wireless network.

So you've taken our advice and bought all the parts you need for your wireless network--now you have to put it all together. While most Wi-Fi devices are relatively simple to install and use (see "No-Hassle Wireless Networking Superguide" for installation tips), coaxing the best performance out of your network takes some effort. Read on for tips to bring your Wi-Fi net up to speed.

Location, Location, Location

Location is indeed everything when it comes to getting the best range out of your Wi-Fi router. Wireless performance drops off dramatically as signal strength falls (from a top speed of 54 mbps with 802.11g to as little as 1 to 2 mbps at the lowest discernible signal strength); so if you can, you should position your router in a spot where all of your computers receive good signal strength.

Ideally, your Wi-Fi router should go in a location at the center of your house or office for best coverage, but you will have to position it near your DSL or cable modem. To test the coverage, do a preliminary installation of your router in the same room with your broadband modem, then connect your notebook PC wirelessly and walk around your home or office, checking the signal strength in the wireless adapter's administration software. Metal, stone, concrete, water, and human beings absorb or reflect signals, while wood and glass let them pass relatively unchecked. So place your router high in the room, as far away from obstructions as possible, parallel to the wall, and away from windows to stop the signal from spreading beyond the building. Also try adjusting the antenna; just as with a TV antenna, even an inch can make a big difference in wireless reception. Have a partner with a notebook in a distant room call out to you as the signal gets better.

If you discover that your home or office suffers a few dead spots, you can add a higher-power antenna; see "Extending the Range."

Try to minimize interference. 802.11g Wi-Fi networks operate in the 2.4-GHz frequency range, the same as microwave ovens and many cordless phones. If you have 2.4-GHz cordless phones and they cause problems with your network, the only solution is to swap them for 900-MHz or 5.8-GHz models.

The other chief source of interference is competing Wi-Fi networks. Wi-Fi has gotten so popular that a single apartment or office building can house multiple networks, all trying to use the same frequency. A free utility like NetStumbler can identify nearby networks. Note the channel numbers of any with significant signal strength, and set your network to use a different channel. Also make sure that your own SSID (network name) is different from the others, so your computers don't try to connect to them by accident.

Enabling WEP or WPA can significantly cut the speed at which data is transmitted. That's why it's important to start with a strong signal, so that the speed loss is minimized. Also, don't fall into the trap of turning off the encryption in order to get better performance--doing so would make it simple for an outsider to snoop on your network. For more tips on how to secure your Wi-Fi net, see "5 Common Wi-Fi Security Mistakes."

Troubleshooting Your Network

If your computer can't seem to recognize your router, or if you can't get onto the Internet, the following basic troubleshooting steps should help (and make tech support phone calls much shorter).

The first thing to do with any network glitch is to isolate the issue. Make sure that both the adapter card and the router are set to the same SSID, encryption mode (WEP or WPA), and encryption key--an error in any of these will lock you out of the network. If possible, try connecting a PC to the router via one of the wired ethernet ports. If you can bring up the router's administration interface on a wired connection, but not with Wi-Fi, check that your Wi-Fi card drivers are installed correctly. Usually the software that comes with the adapters has a testing option.

Also ensure that the adapter card and router are compatible. 802.11g routers may have g-only modes of operation to which 802.11b cards can't connect, or speed-boosted g modes that prevent regular 802.11g cards from connecting. Routers can also be set to allow only those clients with specific MAC addresses to connect to them, as a security measure. Make sure your card is on your router's list.

If you can connect to the router wirelessly but can't get onto the Internet, your card is working fine, but you'll need to troubleshoot your router. Check your router configuration to be sure you set it up properly. Rerun the setup utility, checking the mode (PPoE or DHCP, depending on what your ISP uses) and the user name and password that you use to log on. Be sure the settings match those that your broadband provider gave you. Some broadband modems are tied to the MAC address of the computer on which they were first installed, so you may need to "clone" the MAC address and fool the modem into thinking your router is really your PC.

Check that the wired connection between the router and the broadband modem is firmly seated, and that the indicator light for this connection is glowing. If a light is off, you may have a bad cable, or you might have connected a crossover ethernet cable instead of a regular one. Some routers come with a crossover cable that you use while setting it up--this cable doesn't work for the connection between the router and the modem.

If you get dropouts or lose your Internet connection, make sure you have the latest firmware for both the router and the adapters. Wi-Fi vendors issue frequent firmware updates that address such issues and add new features.

And finally, one last thing to remember: Keep your Windows system up-to-date with the latest patches from Redmond.