Research On Reliable Transmission Of Data Based On Wireless Sensor Network

The wireless sensor network consists of a myriad of sensor nodes with limited storage capacity and limited power. Because of its main application in environmental monitoring, transportation maintenance, medical care and other important areas, so the reliable transmission of data becomes a key security factor.Around the reliable transmission of data, this paper mainly carried out two aspects of studies. Namely, how to construct one network with low cost, low power consumption and excellent performance; how to transmit data safely after the construction.For the construction of network, the deployment of relay nodes based on greedy criterion is easy to implement and easy to expand. But under this algorithm,each node independently generates a communication path to the gateway without observing the node distribution of existing network. Based on this, one criterion that gives priority to the existing relay node and other two kinds of new greedy criteria were presented in this paper, and with the combination of these three new criteria and the recent greedy criterion, a relay node deployment algorithm based on cooperative mechanism is finally obtained. At the same time, the threshold method and the average value method are proposed for the load of the relay nodes. Based on this, the routing method, fault tolerance scheme and the deployment method of nodes were also proposed here.After the construction of network, the data encryption operation is often performed to achieve the purpose of secure transmission. Meanwhile, encryption key stream directly affects the security of the encryption algorithm, and one good quantitative method is the main factor of obtaining the high security key stream.Therefore, for the secure transmission of data, this paper focuses on the quantitative method and random performance of key stream sequence. Finally, one L bit quantification method that can automatically intercept the random bits was put forward. At the same time, the judging standards of the randomness of key stream sequence were summed up in this paper, and two methods to measure the linear complexity of sequence was presented as well.Theoretical analysis and experimental results show that, in the construction of the network, the relay node deployment algorithm based on the cooperative mechanism presented in this paper can reduce the total energy consumption and the construction cost of the network. Two load balancing methods proposed here, such as the threshold method, can clearly balance the load of each node and save energy of each node. In the secure transmission of data, the L bit quantification method put forward here can avoid the link of human interference, and can make the key streamsequence more random. However, the quantification method will take extra time, so it is recommended to be used in the encryption application that only moderate amount of data need to be encrypted.