Delays when WiFi is in use

I’ve noticed substantial delays in execution when WiFi is being heavily used (downloads, streaming video etc).

I have a combination modem/WiFi router with FiOS, so my ST hub is necessarily within 3 feet of my WiFi router. I’m using SmartApps and Hello Home actions in my setup, so my question is this:

From your own experiences with latency, is this likely due to

a) The internet connection itself being throttled, which results in spotty SmartApp execution or
b) The WiFi router significantly communicating with devices and conflicting with, for instance, Zigbee signals from the hub?

Obviously there’s some experimentation to be done to find the right answer for my setup, but I’m trying to decide which to tackle first - buy a length of ethernet cable to try to get the hub as far away from my router as possible OR futz with my account bandwidth/router set up to prevent latency during peak data consumption?

Could be either or both. If it was me personally the first thing I would do is move the SmartThings hub at least 3 m away from the Wi-Fi router. Strong wifi can definitely drown out Zigbee.

What’s your bandwidth? I had a similar problem with my HA when I was on a slower tier. As soon as I bumped my service tier up everything was drastically better.

That seems like a solid starting point, although 9ft of ethernet cable running across my floor is not going to meet WAF standards. Maybe if my router supports 5Ghz I could eliminate the signal conflict without extra cabling?

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I appear to be at 50 Mbps, so that’s a definite candidate. If the router frequency thing doesn’t work I’ll try bumping to a larger tier. Thanks for the benefit of your experience.

@jgpippin It actually looks like your router cannot cope with too much traffic. Sounds like you have an older router (based on not having 5GHz) You might want to look into a newer router.
Also, there was some work lately on smartthings backend.

Late to the party here, but my $0.02:

I’m on FiOS too (although I bought my own router, in part since the Verizon-issue was third-rate). When we were downloading large files or streaming video over 2.4 Ghz WiFi, it would routinely knock the Zigbee devices offline. For example, starting NetFlix on a tablet would result in all our proximity detectors “leaving.”

I was initially inclined to blame Verizon, but I isolated the problem by hooking up 2.4 devices via Ethernet instead and trying to recreate the failures. When I couldn’t do so while using Ethernet, I concluded it was interference.

No amount of tinkering with the 2.4 channel would solve it, however, so I’ve since moved most of our devices to 5GHz WiFi, and it solved most of these problems. (Alas, not all devices support 5).

My understanding is that Zigbee and 2.4 WiFi are close in the spectrum, but that this isn’t the case for Z-wave. (This was consistent with our experience.). So you’re having problems with Z-wave devices, it may not be interference.

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WiFi and Zigbee overlap. (Zwave doesn’t. Typically the only things that cause interference for Zwave are some baby monitors and some older cordless landline phones.) You can also try changing the Wi-Fi channel that your router is using.

Keep in mind that 2.4 GHz standard has a bandwith of 20 MHz so it’s easy to saturate it when having intense activity. Newer routers have the capability to increase it to 40 MHz.
5GHz standard has also 20 MHz bandwith. Newer routers have the capability to increase it to 40 or 80 MHz.
When you switched some of your devices to 5 GHz you freed some bandwith on 2.4 GHz.
The only issue is that 5 GHz band does not travel as far as 2.4 GHz. So moving devices to 5 GHz makes sense if they are closer to the router. Also move devices that require larger bandwith (like tv for Netflix or computers for online gaming).

Correct. They use 900MHz band. It is unlicensed so users can go without going through FCC aproval process to operate the device (obtain license).

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Easy thing to find out is create virtual switches and tie them to your routines and test them during heavy traffic if you think it’s a zigbee problem. If the delay is there then it’s your Internet and not zigbee interference. Also change the channel of you 2.4ghz in your router away from the ST hub channel also seem to help.

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