Zigbee Wireless

ZigBee Wireless is a specification based on the IEEE 802.15.4 standard for wireless personal area networks (WPANs). ZigBee operates in the ISM radio bands and its focus is to define a general-purpose, inexpensive, self-organizing, mesh network that can be used for industrial control, embedded sensing, medical data collection, smoke and intruder warning, building automation, home automation, and domotics, etc. There are three different types of ZigBee devices in a ZigBee network

a c Coordinator (Master): Only one coordinator exists in each ZigBee network. Its function is to store information about the network and determine the optimum transmission path between each point.
a c Full function device (Router, Repeater): Routers act as an intermediate repeater that passes data from other devices.
a c Reduced Function Device (End Device): This device contains a minimal amount of functionality to enable it to talk to its parent node (either the coordinator or a router), it cannot relay data from other devices