【正文】 ecess light, for example, requires new wiring to a switch. If the recess light and the switch are equipped with ZigBee devices, no wired connection between the light and the switch is necessary. In this way, any switch in the house can be assigned to turn on and off a specific light. Figure is an example of wireless connections between wall switches and lights. In our example, the lights are located in a residential building entrance, living area, and hallway. The wall switch in the entrance can turn on and off any of the four lights. The living area wall switch, in contrast, municates only with the lights in the living area. Living area lights are in close proximity to each other, and therefore a single ZigBee device can be used for both lights. The concept of using binding tables (see Section ) is applicable in the example of Figure . Wall switch 1 is logically connected to all four lights. Wall switch 2 is bound only to the lights in the living area. One of the devices in the work has the task of storing and updating the binding table. A ZigBeeenabled recess light can be more expensive than a regular recess light, but the installation cost of a ZigBeeenabled light is lower because it requires no additional wiring to a wall switch. Using wireless remotes to control the lights is not a new concept. ZigBee provides the opportunity to implement this concept on a large scale by ensuring long battery life and interoperability of products from various vendors in a reliable and lowcost work. In addition to potential cost savings, ZigBeeenabled lights can have other benefits in a house. For example, the ZigBee devices embedded in the recess lights can act as routers to relay a message across the house, or the lights can be programmed to dim whenever the television set is turned on. The ZigBee light control mechanism has been used for street light controls as well. Multizone HVAC Systems The multizone control system allows a single heating, ventilation, and airconditioning (HVAC) unit to have separate temperature zones in the house. Zoning the HVAC system can help save energy by controlling the flow of air to each room and avoiding cooling or heating unnecessary areas. Figure is a simplified diagram that shows motors controlling air dampers and regulating the flow of air to different zones. ZigBee devices control these motors based on the mands they receive from the main HVAC zone control panel and temperature sensors. An alternative way of implementing a multizone control system is to connect the zone control panel, motors, and temperature sensors via wires instead of a wireless work. A wired syste m has less flexibility and additional labor cost for wiring, but the cost of the parts might be slightly lower. Total system cost and flexibility for future modifications should be the decision factors in selecting between these two implementation methods. Consumer Electronics: Remote Control In consumer electronics, ZigBee can be used in wireless remote controls, game controllers, a wireless mouse for a personal puter, and many other applications. In this section, we briefly review the application of ZigBee in wireless remotes. An infrared (IR) remote controller municates with televisions, DVDs, and other entertainment devices via infrared signals. The limitation of IR remotes is that they provide o