[jdthomas]

Hmm, I have not read his paper, but based on the article's mention of "divided into 13 channels" this is clearly speaking of the 2.4Ghz spectrum. Rather than try to distribute that evenly, you are FAR better off upgrading your AP and switching to a 5Ghz channel. First, there are far more potential channels in 5Ghz. Second, they are wider bandwidth (40Mhz, 80Mhz if 80211ac). And third, 5Ghz does not propagate through walls as well (a _feature_ when you have neighbors also using the spectrum).

My other thoughts: if he is using 8 channels instead of the standard 3 (1,6,11) then there will be some overlap; 80211 devices tends to better handle in-channel interference. http://en.wikipedia.org/wiki/List_of_WLAN_channels

[hrzn]

You're right; but actually the mention of 13 channels was just for the example. The algorithm works exactly in the same way for the 5G band as well (where you have similar problems as soon as you have a few neighbors using recent Wi-Fi devices).

[jdthomas]

Interesting, glanced through your paper. How do you find real devices behave at constrained channel widths (<20Mhz in 2.4, <40Mhz in 5)? I have a feeling those are not well tested scenarios :)

[hrzn]

All 802.11n devices supporting the 5G band support at least a bandwidth 20 MHz (as well as 40 MHz). In addition, you can use 5 and 10 MHz as well on some Atheros devices with open source drivers.

[ar_turnbull]

I switched to 5g last year, but all of my neighbours have caught up. Worse still — we all have legacy networks on the 2.4ghz spectrum so that our older devices can access the Internet. There are probably two dozen networks accessible from my couch. It's crazy in apartment buildings.

I would suggest that it should become part of our condo fees / building management, but I have little confidence in our board.

[ajhodges]

Not to mention there are many devices that still don't support 5ghz (a notable/annoying example being Chromecasts). Switching to 5ghz is not a solution to the problem outlined in this paper, it's a bandaid.

[breakall]

I have this exact problem: a couple dozen 2.4 Ghz APs are visible to me. Actual throughput at a distance of 6 feet from a 2.4 Ghz router is 1 Mbps (tested with multiple APs). I switched to 5 Ghz and luckily no one else has! Unfortunately, this doesn't solve the problem for all devices -- for example, the Chromecast is 2.4 Ghz only. With the chromecast, I practically can't use the chromecast in a room other than the one that the AP is in. I was thrilled when the Amazon Fire TV Stick came out with 5 Ghz capability. This made it possible for me to stream Netflix, etc. to the tv in the other room.

[swinglock]

Unless he is using more channels than 1, 6 and 11 the article is dangerously poorly written. Unlike what the article suggests, all other channels overlap and will cause actual interference! Do not configure your AP using any other 2.4 GHz channel, even if they already have other APs in range.

[hrzn]

The algorithm takes into account the interference of partially overlapping channels. In fact, it is part of the optimization procedure to minimize this overlap (globally, over all WLANs, but in a decentralized way), while still using as much of the spectrum as possible. This is a general optimization that is relevant for both 2.4G and 5G bands (or pretty much any other band that provides a finite amount of spectrum).