Realization of sleep and reconnecting functions is developed for network systems which comprise a number of end devices, network path sharing devices and coordinators. End devices and, even, network path sharing devices can be enforced to enter a sleep state at the first preset times and wake up at the second preset times. The two preset times are either assigned offline or adjustable at run time, according to the actual traffic load in the network. When a node wakes up, it checks whether the corresponding parent node is in the active state or not. If the corresponding parent node is not in the active state, the node will find a new parent node to establish a new transmission path. |