Abstract: Provided is a terminal node device including: a communication module communicating with an external sink node device and another terminal node device; sensor modules; and a control unit allowing the terminal node device to be operated while allowing the terminal node device to transition into one of the initial, synchronous, and leave states. In the initial state, the control unit scans a received message; if a beacon message is received from a sink node device, the control unit transitions into the synchronous state; and if not for a predetermined time, the control unit transitions into the leave state. Accordingly, if a beacon message is received from the sink node device, the terminal node device transitions into the synchronous state to constitute a server-based wireless sensor network; and if not, the terminal node device transitions into the leave state to constitute an independent sensor network.

Abstract: The present invention is to provide a method and apparatus for multiplexing a sync node and a gateway of a wireless sensor network, which is capable of allowing communication of the wireless sensor network to be normally performed by multiplexing paths of the sync node and the gateway of the wireless sensor network even in the case where any one of the sync node and the gateway abnormally operates and by transmitting upstream data and downstream data through a path selected among the duplexed paths according to characteristics of the wireless sensor network.

Abstract: Provided is a terminal node device including: a communication module communicating with an external sink node device and another terminal node device; sensor modules; and a control unit allowing the terminal node device to be operated while allowing the terminal node device to transition into one of the initial, synchronous, and leave states. In the initial state, the control unit scans a received message; if a beacon message is received from a sink node device, the control unit transitions into the synchronous state; and if not for a predetermined time, the control unit transitions into the leave state. Accordingly, if a beacon message is received from the sink node device, the terminal node device transitions into the synchronous state to constitute a server-based wireless sensor network; and if not, the terminal node device transitions into the leave state to constitute an independent sensor network.

Abstract: The present invention is to provide a method and apparatus for multiplexing a sync node and a gateway of a wireless sensor network, which is capable of allowing communication of the wireless sensor network to be normally performed by multiplexing paths of the sync node and the gateway of the wireless sensor network even in the case where any one of the sync node and the gateway abnormally operates and by transmitting upstream data and downstream data through a path selected among the duplexed paths according to characteristics of the wireless sensor network.

Abstract: A method of transmitting and receiving data for a wireless sensor network system is disclosed. Transmission and reception intervals for a small amount of data and for a large amount of data are set. A sensor node checks data requested to be transmitted. If the data is a small amount of data, the sensor node transmits the data to a higher or lower communication node during the transmission interval for a small amount of data. If the data is a large amount of data, the sensor node divides the large amount of data and then transmitting resulting data to the higher or lower communication node during the transmission interval for a large amount of data. The sensor node receives the small amount of data during the reception interval for a small amount of data and the large amount of data during the reception interval for a large amount of data.

Abstract: A data transmitting and receiving method and a communication system using the method are provided. A transmitting node generates a plurality of data packets by dividing a large-sized data and transmits the data packets to a receiving node at one time, and after that, re-transmits only the non-received data packet(s) which is not received by the receiving node. Accordingly, the number of response packets which the receiving node is to transmit can be reduced, so that it is possible to increase transmission rate.