leviton vizia RF switches (Z-wave)

What is not clear to me is how Z-wave networks determine routing. Does each node only look for its immediate neighbors or all it can find? Also its not clear if the routing structure is node based or shared throughout the network. There are development kits and additional information out there, but I have not pursued any of it.

If I understand the HS addon correctly, it allows route editing to help reach more distant nodes. Again, I have not purchased it so I can supply anything definitive. If that is true, that is great for HS based installations where their Z-troller is the primary. It does not do much good for non-HS installations. Presuming Z-wave grows, there would look to be a market for tools, not unlike the Monterey or Elk X-10 analyzers.

The antennas for the Vizia are located under the paddle. Also they are mounted higher. For now I would assume its a push.

I see that Bass still doesn't understand even the most basic fundamentals of how Z-Wave works. It doesn't matter whether a device only needs to talk directly with a nearby node if the number of hops required to reach the distant device exceeds the max-hops limit. That's why Intermatic added 4 hops.

I also wonder how how it determines which of many possible routes is best. It might take a z-g-zag route and quickly run into the max hops limit. It's supposed to be self-organizing but, at least as far as I understand it, the routing tables are stored in the master controller (although they can now be transferred to secondary controllers). If a network analysis tool is required to fine-tune the network, it would appear that its not terribly efficient at self-organization. So how does a node that is not a controller determine how to address the next hop?

I think it will create a nice market for installers as well as sophisticated diagnostic tools. ;)

snipped-for-privacy@yahoogroups.com

Nor me as that is the normal practice and is the only figure that they can really stand behind.

Elk specifically says their interface has 100' range (in free air). Since all devices from all manufacturers are subject to the same power limits, that figure should hold for all, and my advice that 20-25' minimal indoor spacing is needed for _reliable_ operation stands.

snipped-for-privacy@yahoogroups.com

This from someone who not only has never seen anything Z-Wave, much less tested it, but has repeatedly made inaccurate and misleading statements about Z-Wave.

That is not what I said. Please don't further mislead the readers of this newsgroup. What I said is that a module at one edge of the mesh network does not need to talk to a module at the other edge.

They doubled the number of hops to enable their hardware to service even larger homes and businesses. Even with only 4 hops, Z-Wave has been successfully working in numerous, very large homes. This, despite repeated disinformation which Mr. Houston has posted.

The answer to your question lies in a Z-Wave White Paper a copy of which I have on my desktop (comes in handy actually learning instead of putting forth a question and then supposing the worst possible answer). But I digress.

From Zensys: "The mesh network also serves as the basis for the self-healing functionalities. RF communications links vary over time due to their strong correlation to the physical environment. For example, when a door open/closes, furniture is are moved, or there are simply many people moving about, RF links may fail because the environment is changing. In these situations the self-healing mechanisms in the technology will automatically reroute the message through other nodes until the message reaches the destination node."

How would it "appear" inefficient to this gentleman when he doesn't even know if it exists?

I suggest you read the Zensys white paper on the subject. There's a lot more detail there than I care to post and it will save you from having to "suppose" so many problems and weaknesses.

Hmm. That was rude. Pardon me. I'll post the answer below:

"The Z-Wave installation process is very flexible enabling both local and central installation."

"The local installation is ideal for small low cost systems (e.g. 5 light remotes + 30 lamp modules), which are installed by the homeowner or an installer. The basic philosophy of the Z-Wave local installation process is that the user activates both the node and the controller in order to install the new product. The activation can be simultaneous or skewed and it can be initiated once or for all new nodes depending on the installation scenario. The new product sends out a request to join the network, which is acknowledged by a controller by assigning an ID to the node. Finally the new node reports back its neighbour list (nodes within direct RF range) to the controller enabling it to have full network topology information."

"The central installation is ideal for complex home control Systems with many different products and applications, and which are installed by a professional. The basic philosophy of the Z-Wave Central Installation process is that the Z-Wave technology enables any controller in the system to include new products to the system in coordination with the Z-Wave SIS node. The SIS is typically implemented in a PC or equivalent intelligent device, allowing the installer to have full remote control and monitoring over all steps in the process."

"Zero management of the mesh network -- The central challenge in network management is the fact that the homeowner generally does not fully comprehend that the product he has installed is a part of mesh network. It is therefore important that there is no need for network management in the typical installation. The mesh network must be self-organizing and self-healing."

"Self-organizing -- In a self-organizing network, nodes are capable of discovering their neighbours and distributing this information to others automatically. In a self healing network, nodes are capable of redirecting traffic if parts of the mesh are down."

"In Z-Wave every node discovers its neighbours when they are included in the network or upon request. This information is automatically be forwarded to the Static Update Controller (SUC) in the system. The SUC is always ?listening?, allowing other nodes to receive/request topology information."

"In a self-organizing mesh network the user does not need to consider whether all nodes in the house can communicate directly with each other or whether they need a router along the way. The routing protocol in the mesh ensures that all destination nodes can be reached from any initiator node."

Mr. Houston might want to reread the preceeding paragraph again before declaring that another poster doesn't understand the way Z-Wave works. As I said, a module at one edge of the network does not need to talk to one at the other edge.

However, that advice is not based on experience with the products. Manufacturers disagree. Comments from people who have installed Z-Wave also contradict that advice.

Mr. Houston has repeatedly posted inaccurate information about the protocol, posed questions, supplied his own suppositions as answers and then argued that, based upon those "answers" the protocol is doomed to failure.

Could it possibly be that personal animus or (worse) competition against a product the gentleman hopes to market is involved here?

Note: I sell HA equipment online and I plan to add Z-Wave products from a number of manufacturers to my online offering. As such, I can't claim to be unbiased. However, I try to be forthright in posting information and opinions. Part of that effort includes saying so when I stand to gain from user acceptance of a product or technology such as Z-Wave.

I can email you a Zensys paper if you like. It describes much of this in layman's terms. While it doesn't give you an engineering plan it does answer a lot of these questions.

In article , no-sales-spam@bassburglaralarms (Robert L Bass) writes: | > What is not clear to me is how Z-wave | > networks determine routing. Does each node only look for its immediate neighbors | > or all it can find? | | I can email you a Zensys paper if you like.

I would also like a copy if possible. (Unless it's up on the web somewhere.)

Dan Lanciani ddl@danlan.*com

No problem. I just emailed it to you.

Not here where metal switch boxes are surrounded by wire lath.

snipped-for-privacy@yahoogroups.com

snipped-for-privacy@yahoogroups.com

That is not the page where the document to which I referred is found. I emailed it to Dan at his request.

| No problem. I just emailed it to you.

Got it; thanks! (Don't worry if you got back an error about spam; I retrieved the document and added you to the white list.)

Dan Lanciani ddl@danlan.*com

OK. Enjoy. The doc answers many of the Z-Wave questions that have come up in the newsgroup.

Good point. I live in the land of plastic boxes and textured drywall since they can't build walls straight anymore.

Welcome (back) Dan. Your experience-based comments and advice are always appreciated.

Both PLC- and RF-based lighting are aimed partly at the retrofit market. So the dimensions of the typical existing (eg) US home are of interest when discussing applications of technology that may be limited by geometry and size of homes.

Years of looking at topo maps tells me that the vast majority of existing US homes could work with a primary controller, adjacent nodes and at most one additional hop. In this configuration, each node can communicate directly with every other node (using even only 25 feet is used as the maximum distance). IOW, four-hop "limitation" really isn't.

nodenode+controllernode Outside wall Outside wall

100 x 100 x 1 floor = 10,000 square feet 100 x 100 x 2 floors = 20,000 square feet !

And a 75-foot-long home with a garage 75 feet away (using a conservative

75' free air range is also accommodated. A square one-acre lot is 209 x 209 feet, so a 50-foot-long home in the middle allows coverage of even an entire one-acre lot.

nodenode+controllernode Outside wall Outside wall Lot boundary Lot boundary

( IIRC, the U.S.Geological Survey (USGS) 7-1/2 minute 1:24,000 topographic maps show the actual dimensions of buildings once they reach 40 feet x 40 feet. This is the most common modern paper scale, and a common source of digital/ized maps. This spatial resolution is different than the accuracy of the _location_ of an object. So a square, one-story buildings greater than 1600 gross square feet and two-story homes greater than 3200 gross square feet are shown to scale. (Although in built-up urban areas, individual residences are typically not shown; a red/pink shading for the urban areas is typically used. )

According to the [fact-free, gratuitous bashing of guvmint bureaucrats and public servants typically included here in comp.home.automation] US Census Bureau, the median square footage of new one-family US homes has slowly, and not monotonically, risen from 1525 square feet of floor area (1973) to

2227 (2005). The regional differences are typically less than 10% although homes outside the Metropolitan Statistical Areas tend to be about 15% smaller than those in MSA's. The range for multifamily units is roughly 1/2 the sq footage of single family homes. A majority are =>2 stories.

In other words (allowing for a ~25% reduction from gross areas to net floor area (eg 20,000 --> 15,000sq ft) the median one-family US home is only ~

1/4 (single story) to ~1/8 (two-story) the area that can be handled by a simple configuration in which each node can communicate directly with every other node (using 25 feet as the maximum distance).

So Dan's experience would seem to be overwhelming the rule rather than the exception.

IMO, constant and unwarranted attention by some in this newsgroup to huge McMansions that are statistical outliers (and where Crestron and AMX rule anyway) distorts the discussion and advice given.

... Marc Marc_F_Hult

Deliberately so, it would seem.