What to do when wireless channels are saturated?

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KapsZ28

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The office is about 200' x 100' and is located in a heavily populated city. Currently three Meraki MR26's are setup. Although they are dual band, almost all laptops in the office on have 2.4 Ghz. Below is an image of the wireless network on 2.4 Ghz. The blue star is our wireless of course. The three WAPs are setup on channel 1, 6, and 11 to avoid overlapping with each other. Meraki support tried to assist by enabling band steering and disabling legacy 11b bitrates, but the performance is still pretty bad. I can imagine many other companies in populated areas have to deal with this as well and I would think there would be some type of solution other than getting everyone on a less crowded frequency. Would a better WAP such as the Cisco Aironet 2702 make any difference? Is there anything else that can be tweaked or done to improve performance?



 
Your laptops are too old to support 5Ghz? That is really your only option here. That RF space is trashed.
 
Do the inevitable and move over to 5GHz. How old are the laptops? Even an old ~2007 era Thinkpad has dual band.
 
mi7chy said:
Do the inevitable and move over to 5GHz. How old are the laptops? Even an old ~2007 era Thinkpad has dual band.
Click to expand...


Sadly they are mostly 2-3 years old, but the person that ordered them went with the cheapest wireless card that is just single band.
 
Yeah, buy 5GHz cards for the laptops. Trying to do anything with 2.4GHz is going to a waste of time and an exercise in frustration.

You should be able to get them for like $20.
 
mi7chy said:
Do the inevitable and move over to 5GHz. How old are the laptops? Even an old ~2007 era Thinkpad has dual band.
Click to expand...

Not all newer laptops have 5Ghz. Lenovo is a big offender in this area. Y570? 2.4 only. Yoga 2 Pro? 2.4 only.
 
How about non-tech methods?

One off the top of my head is WiFi blocking paint on the perimeter walls.

http://www.lessemf.com/paint.html

Bad news is that it may also kill Cellular service depending on the frequency. But you can fix that with a cell repeater.

Eventually 5.0Ghz is going to fill up. I'm sure you are not the only one with this problem in the area.
 
Probably requires new equipment, but if both ends support MIMO it might help.
 
It doesn't help that you don't have a signal better than -50. My goal in situations like that are no less than -47 everywhere.

That's actually part of the reason I stay away from Meraki gear. Every sample equipment I've ever had can't manage above -45 even standing right next to it. If you can't beat the neighbors, drown them out.
 
200x100 ft office with walls, bathrooms, cubicles, doors, etc and you are covering it all with 3 aps?

We go a lot more dense than that with interior office environments. Access points are cheap.
 
bds1904 said:
It doesn't help that you don't have a signal better than -50. My goal in situations like that are no less than -47 everywhere.

That's actually part of the reason I stay away from Meraki gear. Every sample equipment I've ever had can't manage above -45 even standing right next to it. If you can't beat the neighbors, drown them out.
Click to expand...

That's pretty optimistic.. -65 is pretty much standard needed for voice applications, most professionals recommend up to a -70 on either 2.4 or 5ghz for full data rates.
 
As many others have mentioned, your only two options are to either 1) attenuate 2.4ghz outside of your service area, or the better plan 2) move to 5ghz. All APs are susceptible to CCC. 5ghz is pretty much the only solution available now to help.
 
green91 said:
That's pretty optimistic.. -65 is pretty much standard needed for voice applications, most professionals recommend up to a -70 on either 2.4 or 5ghz for full data rates.
Click to expand...

If an AIO router/modem combo from an ISP can hit -35 standing next to it, I would expect that a $600-$900 AP should be able to also.....:rolleyes:

Transmission of an analog signal isn't about your overall signal strength, it's about your signal-to-noise ratio.

If your noise floor is -95, sure -65 will work well with VoIP and surfing. You have plenty of power and sensitivity for the job. Right now his noise floor for that is -70, that doesn't leave much breathing room. Once the interference war starts anything less than -30 difference starts to yield high ping and packet loss. As we all know, that is devastating to VoIP and yields an inconsistent surfing experience.

I can't stress how important it is to have a high power WAP in high noise environments.

Either up the power with better WAP's (or more of them) or change to 5GHz. Either way you are going to be spending money.

2 of 5 work days a week of mine are spent fixing wifi problems, both commercial and residential. Dealing with this stuff every day with very large and demanding clients, I can tell you anything less than 30db signal to noise ratio is useless if you need reliable wifi. Optimal SnR for wifi is 35-40dB, that's just a fact.

Heck, Cafe's start to complain if their SnR is less than 25dB.
 
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bds1904 said:
Every sample equipment I've ever had can't manage above -45 even standing right next to it. If you can't beat the neighbors, drown them out.
Click to expand...

Amen to that. So many APS by me that WiFi mostly sucks.

2pg5yNd.jpg


@OP to a certain extent you are at the mercy of those around you. If you have a bunch of pricks using anything other than 1 6 11 for channels then good luck. I have so much crowding that until I got a good AP I onlygot 3-4 Mbps. Even with a unifi I still only get 35 Mbps.
 
bds1904 said:
If an AIO router/modem combo from an ISP can hit -35 standing next to it, I would expect that a $600-$900 AP should be able to also.....:rolleyes:

Transmission of an analog signal isn't about your overall signal strength, it's about your signal-to-noise ratio.

If your noise floor is -95, sure -65 will work well with VoIP and surfing. You have plenty of power and sensitivity for the job. Right now his noise floor for that is -70, that doesn't leave much breathing room. Once the interference war starts anything less than -30 difference starts to yield high ping and packet loss. As we all know, that is devastating to VoIP and yields an inconsistent surfing experience.

I can't stress how important it is to have a high power WAP in high noise environments.

Either up the power with better WAP's (or more of them) or change to 5GHz. Either way you are going to be spending money.

2 of 5 work days a week of mine are spent fixing wifi problems, both commercial and residential. Dealing with this stuff every day with very large and demanding clients, I can tell you anything less than 30db signal to noise ratio is useless if you need reliable wifi. Optimal SnR for wifi is 35-40dB, that's just a fact.

Heck, Cafe's start to complain if their SnR is less than 25dB.
Click to expand...

Sure, SNR is a huge component to having a good performing network. Without a strong SNR re-transmits and the like are going to be a common occurrence, especially in congested spectrum. If you have a 30+ dB SNR and a -65 or greater, you are typically going to have good performance. But, if you have neighboring WAPs in the same channel space with a -85 or better signal in your service area, you are fighting co channel interference. Having a -35 or a -65 doesn't change that. This is why the 2.4ghz spectrum is hosed unless you live in a rural area or have building materials that attenuate well.
 
Edit: Sorry, misinterpreted somebody else's picture as OP's (but why the fuck would even stuff like print servers be on wifi? WTF?)

Anyway, the solution is probably still to get as much as possible off of wifi. Sorry but a business environment should not be relying so heavily on wifi. Wifi is for use on the go or on the couch, not with people who have their laptop at their desk. Just because someone has a laptop doesn't change the fact that they should be using a wire when they are actually at their desk.
 
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