Z-Wave Network map: how to interpret

Hi,

My Z-Wave network looks like this:

Z-wave network

I am unsure how to interpret this.

Node 2, 4, 5 and 6 seem to have good connectivity.
Node 3 is not included in the network but it seems responsive enough not to mark it dead. Is that a correct interpretation? (It shows as online in the things list).
Node 1, the controller, here has no connection to the main network, does that mean the connection isn’t good or is this normal?

Johan, the lines between the nodes indicate mesh network routes. Not all nodes can act as repeaters. Battery powered device can not act as repeaters. In your screen shot all nodes are included in the network and the ones with lines between them represent the mesh routes

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Thank you, Andrew.

You’ll find some useful extra details in this discussion:

Actually the lines depict neighbors which may or may not correlate to routes.

The difference between a neighbor and a route is not clear to me. For example, in my map above, my controller (node 1) does not have any neighbours.

And that makes no sense. PErhaps there has not been a network heal done recently to compute neighbors and report them to the binding.

I know the old map showed nothing much until after a network heal.

There has been a network heal. I added a new device (node 6) yesterday, it is in the diagram and the connections are different today.

I am also not getting any information in my items from the 3 unpowered devices (CO Sensors).

There is about 5 meters and a wooden floor between the controller and the closest powered node (node 6). It is also in the back of a pc, so perhaps it really does have an unreliable connection.

Personally, I have not found a good use for the network map. Sorry.

Any given message sent by any node in the network may not take the same route from device to device through the mesh. So really it makes no sense to worry about routes at all except on a message by message basis.

So instead of showing routes, the map shows neighbors. And to be specific, it’s showing which nodes have heard from other nodes at some point recently.

The orange node is the controller.
The yellow nodes are routers. These nodes can forward messages from other nodes on their way toward their ultimate destination.

The solid green nodes are not routers. Battery powered devices typically won’t be routers.

A line from one node to the next indicates that at least one of those two nodes lists the other as a neighbor, at least one of those nodes has seen the other.

A solid line means both nodes list the other as a neighbor. A dashed line with arrow indicates that only one of the nodes sees the other as a neighbor. In the map above node 4 sees node 6 as a neighbor but node 6 does not see node 4 as a neighbor. Does that mean there isn’t a strong signal between node 6 and node 4? Probably not. All we can say is so far is that node 6 hasn’t seen node 4.

So the map can tell you a little about how strong your mesh is. But it doesn’t really tell you much about the routes that any given message will take to get from point a to point b. And it only really shows a little about the mesh’s health. Take the original network above. Nothing is showing node 1 as a neighbor and node 1 lists nothing as a neighbor. If that meant that there was no route between node 1 and the rest of the nodes it would mean nothing in your zwave network would work. Nodes 2-6 would be marked as dead and no messages would get through to openHAB. But clearly messages are getting through between node 1 and the rest of the nodes or else all the nodes would be marked as dead and there wouldn’t be any arrows at all.

If you are otherwise experiencing Zwave problems the map can help diagnose some things. For example when I started out I noticed certain switches took a long time to switch after being commanded, 10 seconds or more. I pulled up the network map (as it existed back then) and I noticed that only one of my ten devices (at the time) listed the controller as a neighbor and everything else listed that one device as a neighbor. That hinted to me that perhaps I had a bottleneck. That theory made some sense as all mains powered devices were on a different floor from the controller and the one device that saw the controller was directly under the controller.

So I did pretty much the only thing you can do when there is a problem with the mesh network; I bought another mains powered device. I put this one on the same floor but in a different room from the controller. Suddenly all the devices on the main floor started listing that new device as a neighbor and all switching would happen instantly.

So coupling the network map with your knowledge about how the devices are physically located can be used together to help you decide where to put another mains powered Zwave device to improve the mesh. But it doesn’t really tell you much more than that and it doesn’t tell you much on it’s own.

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Just to pile on: One way to examine actual routing and the radio strength (not just neighbors) is with a zniffer. Before I had one, I did waste money on devices that I thought would help routing, but found out they did not.
I don’t know your rules, but for me it’s important that as many nodes as possible have a direct connection with the controller. Mesh is a nice idea for flexibility, but speed increases with fewer hops. The network map in OH3 is almost a magical piece of programming (and provides the info noted in the above posts), but I use a spreadsheet for the routes. I have disabled the heal, so the routes do not change much over time.
zniffer.pdf (231.1 KB)

Bob

That’s not correct. The neighbours list is built up during the heal. There is a specific command that is issued for devices to query their neighbour. Neighbours are only listed if they are a certain signal strength, and if this command fails, then no neighbours will be listed.

The command in question is often difficult for battery devices, and can fail if there’s a lot going on on the network. It’s not just a case of “who heard who recently”.

If there are no neighbours listed for a node, then it is probably because there has been no heal, or, because this part of the heal failed. Of course it could also be because devices have no neighbours with the required signal strength.

OK, I was basing that off of a discussion in another thread so had incorrect information.

Can you please send a link to your sniffer?

It seems to me the only useful way to find out what is going wrong in a Z-Wave network. The network map is useless.

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