Let's talk zwave encryption :)

So I’ve added around 20 red dimmers to my Home Assistant setup and added them all as S2 encryption.

Now I’m not at all concerned about someone hacking my switches from my driveway but was under the impression that S2 was the way to go.

What if any performance hit would I expect to see between no encryption and S2? Looking at range and speed.

I am noticing that the range is fairly disappointing and am curious if this might be a factor.

I am also interested to hear. I have been getting pretty unreliable communication between two of my red dimmers – the two which happen to be S2. I am going to re-add them without security and see how that works. I think I might just go no security on everything except my fireplace, locks, and garage door opener if this actually is causing my issues.

Also multicast is not well supported on S2 nodes, which is also annoying.

I had initially setup all my dimmers and switches to S2 and was having issues. Things have been much better since I re-paired them without security. I’ll be curious to see if anyone knows what could be the cause of this.

I have been searching around today with no luck. Figured there would be some documentation that lists performance benchmarks between no encryption , S0, S2, etc.

I would do none or s2. S0 has a ton of overhead that was addressed in s2. Personally I only do s2 on locks or points of entry.


I suppose going from S2 to no encryption requires an exclusion and association again?

I’m not terribly upset with the speed at which the dimmers respond via zwave commands issued from Home Assistant. More frustrated with the range performance. Anything on Hop 4 is nearly impossible to update firmware on. I should note that the devices on hop 4 are less than 100 feet from the controller with multiple red dimmers in between.

Could this be a symptom of the added overhead from S2?

Hoping to get some good feedback before I go an exclude 20 switches and re add them.

Are you using home assistant with a zwave USB stick? If so something to try is to put your USB stick on a USB extension cable and keep it 3+ feet away from the USB port, and to make sure it’s not in the USB3 (blue) slots.

Electrical noise on that bus is in the frequency range of zwave (~900mhz) so adding some physical distance makes a big difference.

Then do a network heal and reboot after you change that. If that doesn’t help then yeah, I would exclude and reinclude without security.

I have it on an extension cable already. Currently sits about 5’ from my server. Devices closer to the stick update reasonably fast. Switches that are on the 3rd & 4th hop tend to fail firmware upgrades multiple times.

Maybe you need more devices or extenders? I don’t have any devices with more than two hops. I’m running HA with my server in the basement with a 10 ft USB extension hanging from the joist.

I’ve been having some network issues with my z-stick hanging right off of my pi, I had never heard of the interference issue and using an extension cable before so definitely going to give that a try. What is the reasoning for avoiding the USB3 port? Is it because older z-sticks had issues due to the internal wiring or something else?

The power supply driving the USB3 bus radiates noise
centered in the 900Mhz region. The usb2 bus also has electrical noise but less so in that region.

The best performance is on an extension cable in the usb2 ports.

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Interesting. I hadn’t heard that before but an easy fix to try. Thanks for the info!

Is this specifically an issue with USB 3.0 on a Pi or is this for all USB 3.0 setups?

I’m running mine on a home built server connected to a 3 port with a 10’ extension cable.