So what are the best ways to analyse and protect your wireless network from inference – the aim being to keep it in tip top shape, and performing to the best of its abilities.

Some businesses, keen to limit interference on their network, have brought in wireless policies to tackle interference caused by employees or visitors bringing wireless devices into the building. This is a good idea, and will have a positive impact on the level of interference suffered, but does not tackle problems caused by devices found in the office already – some of which might be vital to the business operation (i.e. those cordless telephones and the lunchtime microwave!).

So what about packet sniffers? You can find free software with a quick search online, which will interface with an 802.11 client card and passively capture (‘sniff’) 802.11 transmissions within your wireless WLAN. They will assess and feedback data on secondary indicators of interference, such as increased retransmission and lower data rates, but they won’t help you determine the cause of the inference or tell you where it is located. Given that in order to get rid of interference you would hope to identify the source of the problem and then decide if you want to remove it, this is a major problem and renders packet sniffers slightly impotent.

So what next for your limping, interference addled network? Could you move it to run at 5GHz, as most devices run on 2.4GHz, thus removing most of the problem without having to actually remove the devices causing it? This might bring short-term gain and some improvement, but more and more devices, including some of those omnipresent cordless telephones, are operating at 5GHz, and many more devices will follow. Then you will be back to square one, still hamstrung by interference, and still trying to address the problem.