Is it possible to turn off the 2.4 radio on dual radio APs?

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Is it possible to turn off the 2.4 radio on dual radio APs?
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Bradley Chambers, Champ

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Posted 5 years ago

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Crowdie, Champ

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This is done in the WLAN Interface section of the access point's configuration (Monitor -> [AP To Adjust] -> Modify -> WLAN Interface).



Just set the 2.4 GHz radio's "Admin State" to "Down".
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Larry

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Brad - Why would you want to turn off one of the radios? Just wondering.
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Crowdie, Champ

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The 2.4 GHz signal propagation exceeds the 5 GHz signal propagation when the transmit power of both radios are equal. To counter this effect you commonly set the 2.4 GHz radio's maximum transmit power 3-5 dBm lower than the 5 GHz radio's maximum transmit power. However, sometimes this is not enough, particularly in high density deployments, and you have to install additional access points with only their 5 GHz radios enabled as having both radios enabled would cause large amounts of co-channel interference in the 2.4 GHz spectrum.
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Larry

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Interesting, thanks. So, we are moving APs into classrooms for the first times (used to be strategically placed in the hallways) due to the higher density. However, I think when you refer to "high density" you may be thinking of 50-100 clients and I'm thinking more like 20+. 20 desks in a classroom, all with laptops at any given point in time, etc.

So, do you think this is something that I should consider? Or more to the point, how will I know IF there is large amounts of co-channel interference in the 2.4 GHz spectrum
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Bradley Chambers, Champ

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Yes, crowdie is correct on why you might want to do this. It's all about density and CCI.

I working on an area that is 450+ users in a gym, so i am trying get as many APs in a room as possible. With more non overlapping channels, it's a bit easier to do with 5ghz (assuming client devices support it). As crowdie mentioned, lowering the power of the AP is also a method to limit CCI.

If your situation (depending on what's in the walls, etc), I would make sure you are using band steering and I'd probably do a 60/40 balance. 2.4 isn't bad in itself, it's just tougher to deal with in certain situations. One AP per classroom is my recommendation for edu.

You should be able to see interference charts in the HiveManager dashboard. If you find you are having CCI issues, you might look at lowering the power of the APs in the classrooms (assuming it's one AP per classroom)
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Bradley Chambers, Champ

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I don't suspect you'll have many problems with throughput with only 20 clients per AP, though. That is pretty much what I have on any given day in our classrooms
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Larry

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Okay, I think I get it now. So, in your classrooms you're not shutting off the 2.4 radio, just in this super-high density place (the gym)? I was planning on putting two radios on each separate end of our gym too. And from what you're saying it may seem like a good idea to shut off the 2.4 on each of those APs. Interesting stuff.
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Andrew MacTaggart, Champ

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would just like to add that I had do a reboot on my APs before the disabled radios were actually disabled.

http://community.aerohive.com/aerohiv...
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Andrew MacTaggart, Champ

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well worth a watch as well

http://blogs.aerohive.com/blog/wi-fi-...
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Bradley Chambers, Champ

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Larry,

Yes. It's just in the higher density areas that I don't want a ton of 2.4 radios (but I do want a few). It's important to note that ALL iPads are capable of 5 Ghz, but only the iPhone 5, 5c, and 5s are 5 Ghz.