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Updated February 26, 2007 07:00 PST
What kind of security is on the Z-Wave system? How
do I prevent an external source from turning on or off lights
or systems?
Each Z-Wave Primary Controller ships from the factory with
its own unique house code, no two are alike - unlike legacy
systems that reused house codes from a small pool of 256
possible codes.
All devices that are installed in your home will get their
own device addresses and unique house codes from that Primary
Controller. This process is called Inclusion. In order to
include a device into your home system you must have physical
possession of the Primary Controller and you must have physical
possession of the device you wish to include.
During the inclusion step the two devices need to be in
close proximity to each other, no more than 10 feet apart,
and you must press a button on each device to establish
the connection and transfer the unique house code from the
Primary Controller to the device. Once this inclusion step
is performed the device will only respond to other devices
that share the same home code. There is no way for your
next-door neighbor to control or modify your system.
Can you buy Z-Wave chips to create your own hardware
for items that don't exist yet or is the Z-Wave more of
a protocol and not a hardware solution?
Z-Wave is both a protocol and a hardware solution. To create
Z-Wave products you purchase a System on a Chip or SoC from
Zensys. This SoC contains the physical radio, a microcontroller,
and the Z-Wave protocol stack or software.
Unless you are an OEM hardware manufacture, you would most
likely start with a complete Z-Wave transceiver from a Z-Wave
OEM such as an Intermatic USB stick and build out your application
from there. There are software developers' kits (SDK's)
available for PC and for .NET devices.
Is there open source code for Z-Wave?
Absolutely. Some of our vendors have embraced the open source
and hobbyist communities extensively. For example, many
free projects have cropped up using the Intermatic/Microsoft
HA102 starter kit (with the ControlThink Z-Wave PC SDK).
The xPL project also provides open source support for Z-Wave
products.
Z-Wave is a multi-vector broadcast system. How does
it prevent flooding?
Z-Wave is not a multi-vector broadcast system. Instead,
it is designed based on a highly efficient source routing
algorithm. Therefore, typical problems associated with flooding
are irrelevant for Z-Wave. In this regard it is very different
from technologies such as ZigBee, AODV, Insteon, and KNX
RF that are using flooding-based algorithms for all route
resolution or even for the transmission of every single
command.
The ZWaveWorld.com expert panel includes Mark Walters,
vice president, Z-Wave Alliance; Chris Walker, president
and chief software architect of ControlThink, and ZWW contributing
editor, David Powell.
