Z-Wave improvement

Intermatic announced their InTouch(tm) Z-Wave based system a year ago (March

2006) but it is just now starting to ship. It addresses two Z-Wave weaknesses which I have been pointing out for the past 3 years or so.

First, it increases the maximum number of hops a message can take from 4 to

1. Given that Z-Wave devices need to be within 20-25 feet of each other to assure coverage, 4 hops severely restricted the size of any Z-Wave network and I considered it a fatal flaw in the Z-Wave system. 8 hops is a much more realistic figure.

Second, it employs what Intermatic calls a "server" which is in the base/charger for the handheld remote. It periodically polls all of the devices (including legacy Z-Wave devices) in the network and maintains a status table which can be accessed by other controls.

I still have some questions and haven't been able to find in-depth technical details to answer them.

1. How often is the network polled? The polling frequency will determine how up-to-date the status table is but frequent polling may hamper operations by causing collisions with user generated signals.

1a. Can legacy controllers access the "server"?

1. It's not clear how legacy devices will deal with the increased number of allowable hops. The remaining hops are embedded in the message and it's not clear how legacy devices will deal with numbers greater than 4. Perhaps the original protocol anticipated larger numbers.

Intermatic says they've applied for patents so their approach may or may not show up in other Z-Wave systems.

Prices for InTouch(tm) devices are approximately 3x those of comparable devices in Intermatic's HomeSettings(tm) line of legacy Z-Wave products.

Intermatic has started a forum where those interested can get answers to their questions.

Finally, I don't know how microwavable it is - it uses the 900MHz band in North America.

snipped-for-privacy@yahoogroups.com

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Posted 5 years ago by Dave Houston in General Home Automation

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