Wireless networks have come a long way in the past couple of decades. And if you’ve ever messed around with your Wi-Fi router’s settings, you’ve probably seen the word “channel.” Most routers have the channel set to Auto. But many of us have looked through that list of a dozen or so channels and wondered what they are, and more importantly, which of the channels are faster than the others. Well, some channels are indeed much faster — but that doesn’t mean you should go ahead and change them just yet.
Channels 1, 6, and 11
First of all, let’s talk about 2.4GHz, because even in 2017, the majority of Wi-Fi installations still use the 2.4GHz band in some way. 802.11ac, which debuted in 2013, is driving adoption of 5GHz — but thanks to backwards compatibility, dual-radio routers and devices, and lower-cost peripherals with less expensive chipsets, 2.4GHz will continue to reign for a while.
Fortunately, channels 1, 6, and 11 are spaced far enough apart that they don’t overlap. On a non-MIMO setup (i.e. 802.11 a, b, or g) you should always try to use channel 1, 6, or 11. If you use 802.11n with 20MHz channels, stick to channels 1, 6, and 11 — if you want to use 40MHz channels, be aware that the airwaves might be congested, unless you live in a detached house in the middle of nowhere.
What channel should you use in a crowded area?
If you want maximum throughput and minimal interference, channels 1, 6, and 11 are your best choices. But depending on other wireless networks in your vicinity, one of those channels might be a better option than the others.
For example, if you’re using channel 1, but someone next door is annoyingly using channel 2, then your throughput will plummet. In that situation, you would have to change to channel 11 to completely avoid the interference (though 6 would be pretty good as well). It might be tempting to use a channel other than 1, 6, or 11 — but remember that you will then be the cause of interference (and everyone on 1, 6, and 11 will stomp on your throughput, anyway).
In an ideal world, you would talk to your neighbors and get every router to use channels 1, 6, or 11. Bear in mind that interior walls do a pretty good job of attenuating (weakening) a signal. If there’s a brick wall between you and a neighbor, you could probably both use channel 1 without interfering with each other. But if it’s a thin wall (or there’s lots of windows), you should use different channels.