What would you recommend I do about a congested network segment?

ttabbal

Active Member
Mar 10, 2016
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If they are going to insist on those ridiculous wifi cams, I don't know that you can really fix it. You're running up against physics. Particularly when they are so junky that they are 2.4Ghz only. Even worse if they keep adding new ones. A few with better placement are better by far.

Since you're trying to separate things and want to do one thing at a time, generally a good idea, try something like this..

Disable 2.4Ghz on the AC APs. Swap the APs around so that the 3 2.4Ghz only devices are spread out. Adjust the power on them to minimize overlap using the heatmap tool or even just plotting signal strength. Change the SSID so it's just the cams connecting to them. It's probably best to do this at a slow time so that you can even turn off all the other stuff to minimize interference. And yes, it's going to suck re-connecting all those cams. Yet another reason not to use them. You might also give each AP an independent SSID so you can balance which cameras connect to which AP. Ensure they are on non-overlapping channels. Use the smallest channel width you can. 40Mhz channels on 2.4Ghz is just asking for pain.

From here, ideally, you would then create a VLAN and break them out. You can do that later though. The wired bandwidth is not an issue here, and security won't be any less crap than it is now, so whatever.

Now you can bring up the 5.8Ghz APs. 2.4Ghz disabled. Probably one at a time so you can adjust power levels to get coverage without interference. Every AP needs to be on a non-overlapping channel from any other AP it can hear. So you might be able to use the same channel on opposite sides of the building, but not next to each other. Enable the guest network in the unifi controller for guests. Business stuff can be on the normal network. I think you need VLAN support for the guest network. The switches need to support tagging, at least without mangling the tags, and the firewall needs to be able to separate the networks for routing. Most modern switches can handle this, even unmanged ones. Sure, managed switches are better, for a lot of reasons, but trying to use what you have.

One possible issue is the card terminals might be 2.4Ghz only. You might need to enable 2.4 on a couple of APs for them. This will cause some interference and latency, but card devices don't usually need much bandwidth, so you might get away with it. But with that many devices it might not work well. Do not connect them to the cam APs or channels. You might be able to run 2 of the channels for cameras, leaving one for card readers. The card reader channel will be underutilitzed, but it's more about latency and reliability for those than anything else.

One thing to be sure of and 100% clear on here. If they keep adding these stupid cameras, they will have more and more problems. There is no way around it and no way to fix it. Even if you manage to make things work better with some of the things in this thread, you WILL run into problems eventually. On each channel, only one device can transmit at a time. Otherwise they interfere and have to re-transmit. So right now, you have a minimum 40 devices trying to transmit, just for cameras. Each one needs some amount of time to send their data, and at the very best case, with very careful setup, 3 can send at a time as there are 3 channels for 2.4Ghz wifi. Then you need some time between packets, so that devices can tell they might be able to send, and hope that 2 don't decide to try at the same time, or you start over. To make things worse, the servers those cams are talking to have to send data back to them, even if only ACKs. With wired devices, all devices can both send and receive simultaneously, and can do so significantly faster.

I understand that you are dealing with someone who doesn't want to understand this. But part of a tech's job is selling users the truth. Because the sales people lie.
 
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gregsachs

Active Member
Aug 14, 2018
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Do you have access to the Unifi controller/App?
Look at the utillization on the access points, this will show you the 2.4g congestion. That might be your best shot and convincing your owner that the cameras are a significant part of the issue.
 

Evan

Well-Known Member
Jan 6, 2016
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I am also assuming you have neighbors that also have WiFi competing.
as a general rule in your own building you want the power low so that devices will jump the best AP, but a lot of devices hang on to a poor connection way too long.

you would be amazed how busy the 2.4ghz is also because of its reach, the 5ghz is much better.

not cheap but quality WiFi will have surveillance radios to also survey and pick the best channels and power.

absolutely exhoing everybody else as well, get cables to the cameras if possible.

when you have different SSID going to different VLAN just keep in mind each SSID has its own beacons etc so has overhead, best to keep to 3 or 4 at most.