sensory networks. The ZigBee Alliance was formed in November 2002 with the aim of exploiting the IEEE 802.15.4 radio, and the ZigBee 1.0 specification was finalised in March 2005. ZigBee delivers low data rate communications, up to 250 kbps, with ultra-low power consumption, and aims to provide a device control channel, rather than the high rate data flow channel targeted by technologies such as Wireless USB. Some of the specific steps that have been taken to achieve ultra-low power consumption are; reducing the amount of data that is transmitted including the frame overhead (addressing and other header information) reducing the transceiver's duty cycle including power management mechanisms for power-down and sleep modes targeting a limited operating range of around 30 metres. As a result, a ZigBee network will typically require only 1% of the power of an equivalent Bluetooth PAN, resulting in a battery life of months to years. Two device classes will be defined; full function devices which implement the full protocol stack and are capable of being co-ordinating nodes and connecting with any type of device in any topology, and reduced function devices which will implement a simplified protocol set and will be limited to acting as end-nodes in simple connection topologies (star or peer-to-peer). Every ZigBee network has a unique full function personal area network co-ordinator (similar to a Bluetooth Master device) which is responsible for network management tasks such as associating new devices and Chapter Ten beacon transmissions. In a star network all devices communicate with the PAN co-ordinator, while in a peer-to-peer network individual full function devices are able to communicate with each other. The very low target cost ($1-$5) will make ZigBee ideal for wireless monitoring and control applications such as residential and commercial building automation (smart home) and industrial process control. In the home ZigBee can enable the creation of a home area network (HAN), allowing the many devices currently c