Why? To sell more APs, of course! When in doubt, slap up another AP at 100mW.

At home, channels 1, 6 & 11 are usually crowded...so I use the in between channels as a compromise to minimize the interference...now, business locations may have similar problem as they exist among residential areas so using in between channels is a valid work around! does this count as a good reason?

The problem even using them at home is that you are stil causing interference even on those other channels. Simply because of the way the spectrum works if you have neighbors with radios set on 6 and 11 and you set yours to channel 9 then you just overlapped both of their radios and where ever your coverage meets theirs there will be a dead zone. The absolute only safe way to not have overlap is to stick to your primaries...1, 6, and 11. And I believe any other professional out there will agree with me.

Brett - I'd guess the answer is "Because its there". I have seen a difference in SOHO vs. Enterprise auto-channel algorithms though. SOHO APs seem to pick *any* channel (mine really like 7 for some awful reason), and the Enterprise guys generally stick to 1/6/11 exclusively.

Kamal - That's not a good reason. You're doing yourself and your neighbors a disservice by not using 1/6/11. You will get better real-world throughput if you and a neighbor are both on channel 6 instead of him on 6 and you on 9. You're actually in a much worse position than either of them for performance since they are both going to interfere with you.

For a while there was a belief you could get 4 channels with 1,4,8, and 11. I have seen these floating around in the wild. My current employer had a "professional" company a few years ago come in and that was their method. When I started I was blown away by this but there are some documents out there that argue you can do it. I quickly moved away from this as we were having performance issues. I am not sure if the people you are seeing doing it are "educated" that they have researched and still believe the 4 channel method is valid but if I were a betting man the enterprise wireless deployments are using auto channel. Wireless has the issue of "I can do it at home so how hard can it be?" syndrom. People dont get that at home they have 1 or 2 users not counting their neighbor who is stealing their service. Where in enterprise especially where I am at you have hundreds of users per day. So there is a big difference. So you get an admin that is told to install an AP because their boss has it at home and that admin isnt familiar with channel interference or even how to control the power level of their signal.

About 15 minutes of throughput testing shows that any combination of channels other than 1,6,11 is sub par. How's this for a fact?

It is worse to put two AP's on overlapping channels (i.e. 1 and 3) than it is to have two AP's on the same channel.

Keep preaching it brother... I do every week. :)

Hi Brett,

I'm with you amigo. Right here in my home town, we just opened a new school. NICE place it is. New Macbooks and iMacs everywhere for teachers and staff, new HP wired routers and switches, new computer lab with iMacs - the works...then there's the wireless network. oy. Now don't miss the fact that I love Ben (network admin) - great guy - but he oversees the whole shooting match practically by himself. Is he a Wi-Fi expert, uh, no. Can we expect him to be?...that depends on his time and passion to learn it I guess.

The HP guy says something like, 'hey, we sell Wi-Fi gear too, and 'all you have to do is...' put a few of these APs up here and there and then plug in this controller and voila - instant wireless.' Everything is on auto channel and power selection of course. Now, that wouldn't be "so" bad if he didn't have Apple carts roaming around the place with Apple Airports on them. Every time one of those fire up anywhere in the building, it makes the entire corporate (HP) wireless network go bananas changing channels and power settings. Brilliant. He now has a network in a state of business-hour flux, and no real way to measure statistics (throughput, etc) so as to optimize the network.

This is yet ANOTHER example of a lack of education causing such a problem. I know there has to be a thousand such horror stories out there. I'd love to hear other people's stories right here on the blog.

I agree with you, however, reality is that most wireless APs and Routers today are designed to automatically search for the channels with the least interference within their range of operation. I used to worry about this a lot, but no longer. The methods being implemented into most devices appear to work quite well nowadays.

I would agree that the auto adjusting APs can work well - at least the enterprise gear. Of the few thousand APs we have deployed, with auto channel adjustment turned on, 0 are on a channel other than 1, 6 or 11. I can't say the same for the home stuff... I suspect they do whatever.. but the cause of the APs being on "off" channels I suspect is by deliberate (mis)configuration by an Admin.