I was lucky enough this past week to win 2 ski tickets. Unfortunately they had to be used before 4/14 so I went on Sunday and then again on Thursday. Sunday the conditions were great, the trails were completely covered in snow and I had a great day. Thursday though much of the snow had melted leaving bare spots and the snow that was left was starting to get slushy. Anyone that goes spring skiing knows that conditions can change, and quickly. This thought made me realized how the wireless networking landscape changes as quickly as the elements.
Anyone that runs a wireless network knows the same thing, conditions change. Many times you can have a perfectly laid out channel map, power can be tuned exactly and everything works great. Then something changes and problems occur. Lately we have seen this happen with smartphones acting as hotspots. For some reason many of them use the 2.4Ghz spectrum (bg). Typically in the US there are 3 channels that are used, 1,6,11. The reason is to avoid interference you need “5 channels of separation” and these 3 get you the most usage from the spectrum.
These hotspot devices though tend to do a quick scan and use the channel with the least amount of usage. At home this isn’t really a problem because most homes aren’t running more than one or two access points and in the local coffee shop the same is true, but in an enterprise with dozens or hundreds of access points it is a problem.
What can be done though? I think this is where a wireless management tool really is required. You need to be able to detect when this happens and react. By react I don’t mean take countermeasures and block people from connecting to it. That effectively just causes more interference and makes the problem worse, from a performance perspective, though from a security perspective it would help keep people from using unauthorized devices. You could search people and confiscate any electronic device as they come in, but that’s probably a bit heavy handed for most organizations. FBI, CIA, MI-5 or NSA that may be a perfectly acceptable action but for the rest of us trying to be friendly to customers, guests and partners. Full body cavity searches aren’t really good for increasing visitor traffic…
I think the best approach is monitor and respond. It is easy to create an alert that shows any non-sanctioned access point. Wireless devices are easy to locate with triangulation within a few feet, as long as you have enough detectors. You can even have this screen displayed where any person can see it to remind them to please turn off wireless access points. Most people don’t even give this a though and definitely do not want to impact others, they just don’t realize the impact.
Lastly you can always dispatch an IT administrator to ask them to please turn the device off. It’s possible they don’t know how to connect to the guest network or are having an issue and trying to work around it. If so, and you help them, you earn points for being proactive and instead of being seen as a “wireless cop” you become a friendly IT staff.