Zigbee Router or ZR is an optional network element whose major function is to contribute in mesh routing of network communication. It keeps a routing table and controls local address allocation / de-allocation for its allocated Zigbee End Devices. When a request is given by a router who is not present in the routing table the router will give a route request, which is transmitted all over the network. When the target gets the route request it will then give with the path that has the minimum “cost” or how many nodes it took to reach the target.