Identifying RF Interference

If you suddenly start noticing problems with your network or you experience intermittent difficulty, RF interference may be affecting your WLAN. Identifying sources of RF interference isn't easy, especially if they originate from outside your home.

There are a number of things in your home that can cause interference. I identified the most common causes:

-Cordless phones

- Microwave ovens

- Wireless consumer electronics (speakers, cameras, walkie-talkies)

If you notice intermittent interference when one of these devices is in use, then it is probably the culprit. Another source of possible interference is an adjacent WLAN. If you suddenly start having problems with your network, check and see if there is another AP operating on the same channel.

You can use your adapter's configuration software to identify access points in the area. You also can use a wireless "sniffer" like Nets tumbler to locate an AP interfering with your network. If there is another network interfering with your WLAN, try changing channels on your AP or moving it closer to your clients.

You also can try the diplomatic approach if you can figure out who is running the other WLAN. Perhaps you can work out a solution that allows both of your wireless networks to coexist peacefully.

Insider insight: Make sure that all of your equipment uses the same 802.11x standard. This may seem like a silly thing to say, but it's not impossible for people to grab the wrong device at the store and not realize that they have an adapter operating at a different frequency than the rest of their equipment

In addition, if you have an 802.11g access point and you are operating a mixed WLAN (that is, some adapters are 802.11g and others are 802.11b), you should be aware that some access points might slow down when supporting both standards simultaneously.