Z-Wave Protocol Question - ACKs and Retries

So, I've been having "issues" and just got a Z-Wave Toolbox that lets me do some packet analysis (although, sadly, not too deeply).

Still, when I issue a "Group: All inside lights" ON command, which goes out so several dozen nodes--I'm seeing some behavior I think seems odd.

It looks like the ACK packets are possibly only going back to the "next hop"?

I also don't understand why some things are attempting "5 hops"??? Especially when they are close enough to go directly or with 1 hop--and they seem to be going in fewer hops around the same time.

Look at the hub talking to device 33 (decimal) here-it has all kinds of issues with 5 hops going from the hub's virt node 2; but gets there in 4 hops from node 1. And, in the Z-Wave details, it shows a direct connection.

Also, it appears the ACK from 33->1 at the bottom of the light colored area only goes back to 14 and not the hub (node 1)?? I see a lot of ACKs going to devices and seemingly not the hub.

And, I'm not sure why this is an error? It can have 2 hops (likewise, I don't understand why sometimes it looks like 5 hops are allowed, when I thought 4 was the max).



It seems to me that things get busy--then, rather than holding their breath for a moment, things start trying to route packets around all over the place. Even if there are direct routes.

I have a Toolbox also, purchased before SiLabs put their Zniffer code out there. I've since switched to Zniffer... so my memory of Toolbox is getting dimmer and dimmer.

First.. hops. You should see a max of 6 numbers in that Route column. That's 1 Source, 1 Destination and 4 hops. In that same column, notice the '>' or '<' because that character is telling you the direction of the packet flow. I see a lot of rows where the < is the same as the previous row. Those are retries.

In that last screen cap, you have:
Screen Shot 2021-02-13 at 9.21.49 AM

The first row is Device 34 sending to 2, with a single hop of 131. That worked in one. Then 131 tries 3 times to get the message to 2, probably failing because there's only one ACK and that for that first successful packet.

Remember, the Toolbox is a radio receiver, it may not be in range of all the devices. Clearly the hub isn't. The hub is using 131 to extend the radio range, but Toolbox does not have that luxury. Maybe Toolbox is close to you, and you're close to 131.

Your first screen shot shows the 6 numbers.. and is correct.
Screen Shot 2021-02-13 at 9.31.19 AM

But that first row without a > is odd. Additionally the 154 device is sending a route error indicating that 154 can't 'see' 33 -- it's not a known neighbor. So the hub or device is supposed to receive that and resend using another hop.

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