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Re: In general should the 20/40 coexistance box be checked?

Ronoboogie
Aspirant

In general should the 20/40 coexistance box be checked?

New Nighthawk R7800, In general should the 20/40 coexistance box be checked?  I've seen some posts that say yes but others say no. I noticed that it was checked while reviewing the default setup configuration. Thanks    

Model: R6700|Nighthawk AC1750 Smart WiFi Router
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TheEther
Guru

Re: In general should the 20/40 coexistance box be checked?

In general, yes, it should be checked.  Wi-Fi standards require that routers support 20/40 coexistence, which is functionality to ensure that routers fall back to using 20 MHz wide channels either when devices request it or when neighboring Wi-Fi networks that overlap with the current channel are detected.  Disabling coexistence can interfere with these functions.

 

Note, that the 20/40 MHz coexistence mechanism only applies to the 2.4 GHz band.  Unless you live in a rural area with no other Wi-Fi networks present, there's no point trying to use 40 MHz channels at 2.4 GHz.  A 40 MHz channel uses 2/3rds of the frequency spectrum available at 2.4 GHz, which is very unneighborly.  You would be better off using the 5 GHz band, whenever possible, because 40 MHz channels are allowed, even 80 MHz.  You also can take advantage of 802.11ac Wi-Fi which uses superior modulation schemes for overall faster speeds.

 

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netwrks
Master

Re: In general should the 20/40 coexistance box be checked?

Yes, you should. It's called a "Good neighbour policy". You can clobber other 2.4ghz wifi user's in your neighbourhood, with interference. Here's an SNB discussion on the subject. In this instance, take the narrow band! (20mhz)..

Message 2 of 5
TheEther
Guru

Re: In general should the 20/40 coexistance box be checked?

In general, yes, it should be checked.  Wi-Fi standards require that routers support 20/40 coexistence, which is functionality to ensure that routers fall back to using 20 MHz wide channels either when devices request it or when neighboring Wi-Fi networks that overlap with the current channel are detected.  Disabling coexistence can interfere with these functions.

 

Note, that the 20/40 MHz coexistence mechanism only applies to the 2.4 GHz band.  Unless you live in a rural area with no other Wi-Fi networks present, there's no point trying to use 40 MHz channels at 2.4 GHz.  A 40 MHz channel uses 2/3rds of the frequency spectrum available at 2.4 GHz, which is very unneighborly.  You would be better off using the 5 GHz band, whenever possible, because 40 MHz channels are allowed, even 80 MHz.  You also can take advantage of 802.11ac Wi-Fi which uses superior modulation schemes for overall faster speeds.

 

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Ronoboogie
Aspirant

Re: In general should the 20/40 coexistance box be checked?

Thanks

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Ronoboogie
Aspirant

Re: In general should the 20/40 coexistance box be checked?

Thanks

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