Do z-wave repeaters have to talk directly to hub?

Hi All,

I have several z-wave repeaters (Aeotec RE6's and 7's) in my house, and have switched to using the super informative Iris driver for them.

There's a nice "test communication" thing in there. And I've noticed the repeaters that are closer to the hub pass this test easily (30 out of 30 received), but the ones that likely have to use an intermediate device to talk to hub do not.

Do repeaters, by definition, have to talk directly to the hub? They all say they're on Lifeline with hub. And I've repaired the mesh multiple times over weeks/months.

Basically, are these repeaters even working?

I have many other z-wave devices in the house, but none of them have this test ability.

Thanks!

I can't address your post in any technical way. But I know that z-wave repeaters do not have to communicate directly with the z-wave controller.

Edit: They are still working if they are not. I have a sensor that connects to my Hubitat via an Aeotec Range Extender 6, which in turn connects to the Hubitat via a Zooz dimmer.

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That's what I thought... just odd they're failing the communication test. I worry they're not functioning as intended...

The ZWave specification limits the number of hops to 4. Therefore Routers are not required to be direct.

Hop limit of 4 means the 3rd and 4th hops are not direct. If they were able to be direct, then that path wouldn't need the extra hop. :smiley:

I just wrote this in another post, but it bears repeating. My apologies if you have already read it:

The following is from a much quoted document on making up a good zwave mesh:

3. Place the hub in a central location

Putting the hub in a corner of the basement might be convenient, but its a terrible idea for Z-Wave. The hub is the most important node in the network and should have the best location possible. While Z-Wave is a mesh network and can route or hop thru other nodes in the mesh, each hop is a significant delay and chokes up the network with more traffic. Ideally the hub should reach 90% of the nodes in your Smart Home without relying on routing. If the hub has Wifi then putting it in a central location is easy, you just need a wall outlet to plug it in. I have my hub hung off the back of a TV cabinet in roughly the middle of the first floor of my home.
(bolding - mine)

Totally. But, situations be situations. I can't currently put hub central. I hope to soon. I need to run more cat5 to the closet I want to put hub in.

I don't see any way any of my stuff is more than 2 hops from hub... my house isn't that big.

Two points:

  1. A key word above is "ideal". Not everyone can make that happen.
  2. I suspect, that the new hub, the c7, will obviate this question due to its increased range (for zwave). Of course, at present, this is just pure speculation.

Yup. But I do want to move the hub, I've just been procrastinating about running more cable.

per the c7, and the zwave 700 chip in general, they're kinda nebulous about range extension from 500 to 700. Everything reads a bit like "we're being purposefully vague". Like, with with 300 to 500, they said 250% better range or whatever. With the 700, it's unclear on each point if they're talking about improvement over 500 or over 300 or both. =/ But yeah, I'm hoping the C7 will be better. But I'm also hoping in the next few weeks I'll be able to run some cable and get my C5 into the center of my house.

I would also assume that after repositioning the hub, you would have to run a zwave repair for the new routes to take effect.

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oh, absolutely.

I'm not sure about how the test comm works for the iris driver... I wonder if there's a flag that can be set on zwave frames to say don't relay... or the fact they're in the lifeline group. just weird.

If you want to know how many and what hops your z-wave devices take you can build a zniffer or buy a z-wave Toolbox. I have the later, but with some use/learning/testing/tweaking either can tell you a lot about the "health" of your wave mesh.

I do have a zniffer. I never saw hop count as something visible. Only the rather useless checkerboard showing what can see what.

have you tried repairing your zwave network?

yes, many times, as indicated in original post. =)

Oh I don't have that, so not sure what it does. With Z toolbox I can run the packet analyzer and it will show a log of where each device routes. I have seen a couple "4 hoppers", but I try to eliminate that when I do.

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yeah. zniffer, fwiw, is monitoring zwave traffic. I have another zwave stick that I can use with Zwave PC Controller, but it only shows a checkerboard thing. I suppose there might be a way to use either/or to see how stuff routed. All my stuff at this point is zwave plus, so it SHOULD detect optimal routes automatically...

Just have a feeling this is a device issue rather than a zwave issue (the device is only wanting to talk direct to hub or something). Or for some reason it's not updating properly on a repair. Could try an exclude and rejoin...

Zniffer has a column labeled "Data" and for routed traffic, that column contains the route info.

ZWave predefines the route and includes ahead of the payload.

ZWave Frames

Routed packets have the Hop Count and 2 slots for sequential repeaters.

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So here's a zniffer output from running the test against one of the failing repeaters. Interestingly, the src and dst are reversed.

8	15.07.20	16:52:05.999	9.6Kbit/s	54	1	34	29	1	E08EA596	Singlecast	NOP Power	E08EA5961D410B0E010118F00013
9	15.07.20	16:52:06.211	9.6Kbit/s	53	1	213	29	1	E08EA596	Singlecast	NOP Power	E08EA5961D410B0E010118F00013
10	15.07.20	16:52:06.483	9.6Kbit/s	52	1	272	29	1	E08EA596	Singlecast	NOP Power	E08EA5961D410B0E010118F00013
11	15.07.20	16:52:06.618	9.6Kbit/s	52	1	134	29	1	E08EA596	Singlecast	NOP Power	E08EA5961D410C0E010118F00014

zniffer just crashed on me, so can't look deeper yet.

so, seeing occasional successes randomly, but definitely being routed weird. Odd that path discovery would do what it's doing. And ending up at 3 hops because of that weird routing. Kitchen repeater->Outdoor Outlet->Garage Repeater->Hub. That's the ACK.

Now just watching it, it looks like it might have removed the outdoor outlet from that path... am seeing Explorer packets...

Yeah, think the only way I'm going to "fix" this is to move the hub central. sigh guess I know what I'm doing this weekend. lol.

Wish you could manually correct bad routes... lol.

Maybe it's the vintage, but I'm seeing more 'decode' than you're showing.

Singlecast <- those are 'directly connected' no routers. The packets can be smaller by the 'routing table'.

Routed <-- those are packets to destinations that are not directly connected. :slight_smile: And the packet is increased by Hop Count and the 2 'slots' for routing. You can see in the decode I've pasted, that:

Source = 42 and Destination is 1 (the hub.) It's a unsolicited message from a MultiSensor 6.

The Data column shows:
Routed:(42)-> 10 - 34 - (1)
And the next line is the same, Except the -> is moved one to the right... same with the 3rd packet.

Took 3 packet intervals to get the message from the MultiSensor to the Hub and then the Hub ack'd the message with another three packets. 9600 baud, and 200ms to make the entire round trip (497-295 = 202ms) Therefore, a) 100kbit speed or b) a direct connection would reduce 200ms, which is as slow as it can get, to something less, maybe 4ms.. given the singlecast at the top is 40k and completes the round trip in 9ms.

You can... just move the hub manually.. :smiley: or Manually install more repeaters. LOL

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