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by blindriver 37 days ago
One thing that wasn't mentioned is that the more APs you have, the worst off your life gets. That's because the way clients connect to a particular AP is done client-side and you have no control over it or visibility. So, no matter how you fiddle with it, your client may connect to the AP that is 40 feet away and on another floor rather than the one that is 10 feet away with a perfect line of sight. And you won't know why. This is the problem I had with my house and had to decrease the number of APs to get over better reliability and performance.
3 comments

There's band steering. You absolutely do have control, if you opt to do so.

On openwrt, DAWN or usteer can both help your APs to get sounding maps from clients and to tell them which AP to join. Looking at the sounding maps is very fun data to see: highly tecommend! The settings aren't the world's greatest but they are pretty good starts! https://github.com/berlin-open-wireless-lab/DAWN https://openwrt.org/docs/guide-user/network/wifi/dawn

Multiple APs are really nice because you can turn down the AP power, ideally, as you add more stations. Unfortunately I don't think you can tell a client to be quieter though; someone's laptop can be at 200mW tearing the hell out of the spectrum when everyone else is nicely conversing at 10-20mW.

Band steering doesn't work great. Neither does minimum RSSI. It's completely client-dependent and it's a headache. The best solution is to always minimize the number of APs you have with as little overlap as possible because of how unpredictable client behavior is. Like I said I have a very bad problem with line of sight APs are ignored for further away APs, and no amount of fiddling is helping.
This runs contrary imo to a lot of people's experience with for example Google Mesh, which is a product that I dare say works quite well for most people & most devices.

Agreed that signals like RSSI are device dependent. And open source software like DAWN is not the best at adjusting to this automatically. But in principle, most devices will give your AP a sounding map on request, and most clients will obey instruction to move to a different AP. Even really bad devices have generally worked ok for me at this.

The counter advice if use the minimum number of APs leaves pretty large zones of bad reception, and still already accepts the problem of roaming for many people. It's my hope that open source et al get better, get more competitive with what is clearly possible, especially given that we seem so well positioned to have control that could make good decisions here. To give up, when we have so much rich data & options, does not tempt me.

My experience with DAWN wasn't great. Some of my clients don't like the extensions you need, so I had to go back to no roaming extensions and just hoping clients make good decisions and tuning ap power levels to help.

Might try it again though, I'd love for it to work. And I was also dealing with some baseline wifi instability that I think firmware updates has resolved.

From what I hear, Macs are stickier and Windows clients more promiscuous. So a Mac will stick with an AP further out when you have one near, on the other hand a Windows client can go back and forth between APs -which can sometimes be a problem too.
If a device can still hear a farther away AP at say -62 dBm it’s not going to start searching. Searching has a cost in lower speeds and higher latency due time spent tuning to other channels. It’s only done if the current signal weakens. Decrease AP transmit power until each room only has one AP signal at -67dBm or louder. https://support.apple.com/guide/deployment/wi-fi-roaming-sup... Intel Wi-Fi cards have a roaming aggressiveness setting.