
THE FUTURE 221
IEEE 802.15.4 (ZigBee)
ZigBee is an emerging standard for a network layer based on the Institute of Electrical and
Electronics Engineers (IEEE) standard 802.15.4. It is a low-power, always-on, physical and
media access control protocol designed specifically for low-power, low-latency communi-
cation with sensors and control devices. This simple protocol can be implemented on inex-
pensive hardware, requires very little power, and can support a large number of sensors
and controllers with very little latency. Expect to see ZigBee compatibility in many devices
around the home and in RFID readers in the near future. In addition, active RFID tags
may themselves be ZigBee-enabled, allowing them to interoperate with generic manage-
ment systems designed for other building automation, home automation, and manufac-
turing purposes.
Jini
Jini is a technology developed by Sun Microsystems that allows devices to dynamically
discover each other and work together on a network. A simple example is probably more
suited to our purpose here than a long discussion of remote invocation and Java spaces.
The classic example is a Jini-enabled car and cell phone. The phone, upon entering the
car, searches for devices that describe themselves as having speakers. The phone then
downloads interface software from a speaker that allows the phone to use that speaker
when a call comes in. When the phone is removed ...