New Smart Home Network Standard Debuts
- Next month, a host of new wireless gadgets designed to help make
buildings and homes "smart" will debut at the ZigBee Open House and
Exposition in Chicago. Among them will be a so-called domestic
awareness system that warns you if the stove is left on or if the
basement starts flooding. Another lets you network your home
entertainment system with environmental controls such as light dimmers
or a thermostat. The point of such a setup: to automatically set just
the right mood when you're watching DVDs or listening to music.
Underlying these systems is a new wireless-networking standard called
Developed by the ZigBee Alliance--which includes Honeywell, Samsung,
Mitsubishi Electric, Motorola, and some 160 other companies--the
standard allows household appliances, sensors, and other devices to
talk to each other without the need for connecting cables.
Of course, this is by no means the first attempt to boost the IQs of
buildings and homes by networking their components. So can ZigBee
finally deliver home and building automation? Yes, says Chris Ryan, an
analyst with U.K.-based Future Horizons who has been following the
"The problem in the past is that adding thermostats, lighting
controls, and environmental sensors to buildings has been expensive,"
Ryan says. ZigBee technology could cut installation costs dramatically
by letting you install a light switch, say, or a heat or moisture
sensor wherever you want in a building just by sticking it on a wall,
floor, or ceiling. The device's embedded ZigBee chip--which costs less
than five dollars--would then link up wirelessly with the appropriate
light fixture or alarm, saving the exorbitant cost of installing
cables or wires in the wall. This kind of cost savings can make a
significant difference both to the owners of large commercial
buildings (which is ZigBee's initial target market) and to homeowners.
Whereas many earlier smart systems used proprietary technology, ZigBee
is built on an Institute of Electrical and Electronics Engineers
(IEEE) global standard, 802.15.4, similar to the standards that govern
Bluetooth and Wi-Fi. Open standards encourage innovation and
competition, which bring down costs.
But unlike Bluetooth and Wi-Fi networks, which require central hubs
that distribute information to dispersed devices, ZigBee allows
devices to form mesh networks, where each unit can relay information
to its neighbors. Mesh networks are far more robust than their
hub-and-spoke counterparts; if a node breaks down, other nodes can
automatically reroute transmissions around it. That's a big advantage
in something like a building-wide lighting system: you wouldn't want
one bum switch to bring the whole thing down. What's more, mesh
networking could let ZigBee systems link as many as 64,000 devices;
Bluetooth networks, by contrast, are limited to just eight.
Homeowners' first taste of ZigBee is likely to come in the form of
adaptors into which lamps, stereos, and other appliances can be
plugged. The adaptors, which started shipping this summer,
are activated by wall-mounted wireless switches or even handheld
devices, which means you could soon have your whole house on one