Zigbee (TM) is a similar communication protocol to that used by WLAN systems or GPS communications. It is, however, commonly utilised to create personal area networks with smaller and lower powered digital radio technology. Using a protocol based on IEEE 802.15.4 , Zigbee (TM) tends to be suited to applications where low data rates are unproblematic, meaning Zigbee (TM) modules are ideal for situations which call for a long battery life in the field, as well as a very secure approach to network communications. Due to the low-power design, the system means that only relatively low transmission distances can be achieved, typically from ten to one hundred metres. A distinct advantage, though, is that the modules can be extremely small and manufactured to be impressively discreet, when installed. The data rates of these industrial communication devices vary from about 20 to 250 Kilobits per second. ZigBee (TM) device objects, or ZDOs, are also available which offer predefined applications. These can be customised to integrate into a number of device types and can then be put to work with specific tasks, such as tracking device roles and managing requests to join a network. Typical applications of the Zigbee (TM) communication system include home entertainment controls, medical data collection and industrial safety system monitoring.