I have learnt avoiding using wifi smart home devices in the hard way

Hardware
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I have learnt avoiding using wifi smart home devices in the hard way. Just want to share my experience here to avoid using a lot wifi smart home devices unless you really know how to scale up the capacity of your wifi network.

And I am also wondering if anyone have any suggestion on solutions to connect 80+ IP devices without using ethernet as backhaul for APs.

I have to also mention that I don’t have background on the wifi network and I mainly learnt stuffs on WiFi network by making attempt to solve issues. So hopefully my attempts are not totally naive.

In my 1st part of period of using wifi smart devices, I mainly uses a few Yeelight wifi bulbs when I started my smart home journey with some Aqara ZigBee sensors. Later on, I started using HA and left the Aqara ecosystem to start buying cheap but good value wifi bulbs/plugs on amazon because I can integrate them into HA. Despite there are a lot of comments in the community forum talking about that wifi is the worst smart home protocol and it will slow down the internet, I was not taking that seriously because I was very happy with my wifi smart home devices connected by mesh routers at that time. One is connected to the modem and acts as a router and an AP. Another one is located upstairs and acts as an AP because I don’t have ethernet cables embedded in the wall for wired-backhaul. My setup at that time is below:

Modem

← Main Netgear Router+AP connected by Ethernet downstairs (wifi name: Home_2G, Home_5G, connecting ~20 devices)

---- Secondary Netgear AP connected by wireless backhaul upstairs (wifi name: Home_2G, Home_5G, connecting ~10 devices)

In my 2nd part of period of using wifi devices, I started to buy more wifi smart home devices until I had around 60+ IP devices. At that point, my wifi mesh router just kept restarting now and then. My smart home devices were not responding sometimes either. After some investigations and research, I realized there was huge latency if I ping the smart devices, and sometimes packet just got lost. This is because a home-use AP on each radio, 2.4Ghz in this case, can only takes about 30 devices comfortably. More than 30 devices, the channel get jammed and it reduce both throughput and latency even lost connection. At that time, I started to realize despite that smart home devices take very little bandwidth throughput, they can still jam your wifi network if you put too many in the same wifi channel. Lessons learnt! I had to use more APs to mitigate this problem. So I went on ebay and get two second-hand old TP-link routers as my dedicated smart home device APs. The DHCP and 5Ghz band are turned off and the wifi name of 2.4Ghz band is configured differently for each AP so that I can make sure no 2.4Ghz AP takes more than 30 devices. After connecting these 2 extra APs, all the issues mentioned before are gone. Yeah! I thought I finally found a cheap scalable solution for wifi smart devices. Just adding another cheap second-hand TP-link AP and I can connect 30+ more 2.4Ghz smart home devices. Apparently, I was too young and too naive. My setup at that time is below:

Modem

← Main Linnksys Router+AP connected by Ethernet downstairs (wifi name: Home_2G, Home_5G with channel 1, 44, connecting ~5 devices)

---- Secondary Linnksys AP connected by wireless backhaul upstairs (wifi name: Home_2G, Home_5G with channel 1, 44, connecting ~5 devices)

← 1st TP-link AP connected by Ethernet downstairs (different wifi name: IoT_1, channel 6, connecting 25+ devices)

← 2nd TP-link AP connected by Ethernet downstairs (different wifi name: IoT_2, channel 11, connecting 25+ devices)

In my 3rd part of period of using wifi devices, I started to buy more wifi smart home devices until I had around 80+ IP devices. I never had any issues with wifi smart home devices once I added 2 extra TP-link APs. But I started to have long buffering time occasionally when I streamed on my favorite Chinese streaming websites. Considering the web server is in China, I initially thought it was the web server problem, but it puzzled me that I did not hit this issue if I use mobile data. I ended up doing a lot of troubleshooting for a few months and eventually I found out the issue would be gone if I reduce the number of IP devices in the network. So this time the problem is not about how many devices each AP can connect but how many devices each router can connect within the same subnet. I have tested my main Linksys router’s limit. It can only take ~60 devices without dropping performance on video streaming tasks. My solution this time is to have 2 levels of routers in the network, i.e. double NAT for the second router. So the level 1 router, Linksys router, only saw ~25 devices including all streaming devices. And the level 2 router, google wifi router, saw about ~50 smart home devices. My HA instance is in level 2 subnet and it can access devices on level 1 subnet but devices on level 1 subnet cannot access devices in level 2 subnet unless worked around by port forwarding. My setup at that time is below:

Modem

← Main Linnksys Router+AP connected by Ethernet downstairs (wifi name: Home_2G, Home_5G, connecting 15+ devices, Gateway IP: 10.1.1.1)

---- Secondary Linnksys AP connected by wireless backhaul upstairs (wifi name: Home_2G, Home_5G, connecting 10+ devices)

← Google wifi router connected by Ethernet downstairs (wifi name: IoT, connecting 25+ devices, Level 1 IP: 10.1.1.20, Level 2 gateway IP: 192.168.1.1)

← Google wifi AP connected by wireless backhaul upstairs (wifi name: IoT, connecting 25+ devices)

This works perfectly in terms of video streaming performance and all other smart home activities. The only drawback is that some usecases cannot be easily solved by port forwarding. E.g. (1) ipad on level 2 subnet cannot airplay to TVs on level 1 subnet (2) if ipad was connecting level 1 subnet, it cannot be used as Homekit hub for level 2 HA instance (3) my sonos phone app on level 1 subnet cannot connect to sonos speakers on level 2 subnet. After some investigation for the last few month, my next experiment would be using an x86 machine running OpenWRT as a router to provide better performance in terms of routing capability. And I will try to put all 80+ devices under the same subnet again. So I am thinking something like solution 2 but using a dedicated router:

Modem

← x86 OpenWRT router+switch connected by Ethernet downstairs

← Main Linnksys AP connected by Ethernet downstairs (wifi name: Home_2G, Home_5G with channel 1, 44, connecting ~15 devices)

---- Secondary Linnksys AP connected by wireless backhaul upstairs (wifi name: Home_2G, Home_5G with channel 1, 44, connecting ~10 devices)

← 1st TP-link AP connected by Ethernet downstairs (different wifi name: IoT_1, channel 6, connecting 25+ devices)

← 2nd TP-link AP connected by Ethernet downstairs (different wifi name: IoT_2, channel 11, connecting 25+ devices)

That’s my journey so far on scaling up my wifi smart home devices network. I also got ~100 zigbee and Bluetooth devices. Zigbee/Bluetooth devices are annoying in the pairing process when migrating from an old hub to a new hub that you have to manually connect all of them. Unlike wifi devices, you just need to update new AP wifi name to the old wifi name. But once you have done the migration, you can expect Zigbee/Bluetooth hubs work stably most of time until you hit the limit of the number of devices supported by the hub. Even some devices become offline or unstable, it won’t affect your main wifi network for your daily work. Nevertheless, the reason why I choose wifi smart devices in the first place is that they are much cheaper, with more choices, with reasonably good quality e.g. I am using Lepro GU10 bulb with 100 degree beam and there is no Zigbee/Bluetooth replacement with that wide angle that I am aware of. Last but not least, despite that the new protocol Matter is on a higher level similar to Homekit, I am still hoping it would make the whole smart home ecosystem better and manufacturers can provide more unified hub to solve the smart home device scalability problem easier.

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I have about 120 wifi devices spread over 3 Unifi AP Lite access points with wired backhaul to a 48 port switch and Edgerouter. No VLANing (though my mobile devices connect via 5G and all the IoT is 2.4G). Works flawlessly.

If you were to stick with wifi, upgrading your access points and running some structured cabling for the access points and cameras would probably solve all your issues.

Having said that I am also experimenting with zigbee and have found it to be very, very good. Can’t be beat for battery powered devices. I got some good advice and started with an excellent zigbee adaptor from Tubes. I like messing with electronics and ESPHome and the vast array of custom devices this supports though so will continue to be using wifi for IoT for the foreseeable future (especially if ESPNow gets added to ESPHome).

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Ditto , plus about the same number of wired. I try and use wired where practical but still a lot on WiFi. In fact my definite preference is WiFi over Z-Wave or ZigBee.

Yes - you need capable AP’s to avoid this and defer to 5G where possible. If you must use a Mesh use one where the backhaul is wired - or on a different band if you can’t use cable. Not a 2.4Ghz backhaul.

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:rofl::rofl::rofl:

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It’s not really a competing standard to wifi tcp/ip. It’s a peer-to-peer mesh communication method for areas with poor coverage.

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Well, seems a pretty good definition of Matter, isn’t it? :wink:

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What I mean is that ESPNow is not trying to unite a heap of competing standards. It’s its own thing.

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Yeah, well, it might not try to unify anything, but that’s still an additional “standard” which, at first sight, is so similar to Matter that one could wonder why they created their own…

Makes even less sense considering Espressif is part of Matter, and that you can actually run it right now

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True.

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ESP-Now is nothing like Matter.
Matter tries to unify protocols from different vendors. It requires that the protocols have a common standard interface to bridge them.
ESP-Now is trying to remove layers in the TCP protocol to make less overhead. This will make it incompatible with TCP and also Matter, and therefore it will be requiring a gateway to bridge to TCP and Matter. ESP-Now is an attempt to get a communication that is more like to RF433.

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They are both built above WiFi, although not at the same OSI level, indeed.
Matter is a totally new protocol. It doesn’t “bridge” anything.

Strangely, Espressif states in the front page “without using Wi-Fi” but then in the user guide “ESP-NOW applies the IEEE802.11 Action Vendor frame technology”. 802.11 is basically WiFI at the physical layer :slight_smile:

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Matter is in its first release built on top of Wifi and Thread, which is built on top of IPv6. It also uses BLE for provisioning. They are using all the layers of the TCP/IP stack and should be compatible with network equipment running on these protocols.
And by bridging I meant that Matter built on top of standard network stacks to provide a common shared interface between many vendor protocols.

ESP-Now goes the other way. It removes layers from the TCP/IP network stack and thereby removes compatibility with the IP network stack. ESP-Now is an ESP-to-ESP-only protocol. It does not run on Wifi.
ESP-Now can make a fall-back to Wifi if ESP-Now fails, but that is then not ESP-Now anymore.

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Thanks Tom for the advice. I am surprised that 3 UAP-AP-Lite can connect 120 devices - averaging 40 devices per AP. I thought this was only practical only up to 30 devices per AP. I’d like to try this and get someone help me install the ethernet cables running outside of my house.

I probably don’t need the 48 port switch at this stage. But I am not sure about is how powerful the unify switch I need for 80 IP devices. Do you know if I need a powerful ethernet switch for switching many wifi devices and do you have any recomandations or references that I can look at?

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Unifi won’t be your bottleneck for that it’s prosumer but not quite enterprise quality gear. Hundreds of clients aren’t an issue - get Wifi6 aps if they’re available. Your issue will be availability of gear. Unifi stuff has been hard to source for most of 2021

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Thanks, Nathan. I did some research and managed to place order on a new UDM and a second hand UAP-AC-PRO to start with. (Just had a habit of sourcing second hand stuffs and upgrade later :slight_smile: )

The AC-PRO is still using a wirelessly backhaul for now so it’s not in its best performance at the moment. But the whole system is very stable and managed to connect all my 80+ IP devices under the same subnet conformably. Thanks Tom and Nathan for the advices.

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