Research On Platform Construction And Key Technologies Of Software Defined Wireless Sensor Network

In recent years,thanks to the growth of the market demand in the Internet of Things,Car Networking and Smart Home,wireless sensor network(WSN),as a typical kind of wireless multiple hops networks,plays an increasingly important role in our life.WSN can be rapidly deployed.Its flexibly self-organized networking and low cost are also its advantages.With the wide use of wireless sensor network,the traditional form of it has exposed some problems.Due to the limited node energy,the network can only afford to run one routing protocol in the same scene,cannot adjust the routing mechanism according to the changes of application requirements,so that the network topology may become unstable even collapse if some of the nodes run out of energy.This paper propose a kind of wireless sensor network system based on software defined network(SDN),introducing the idea of data and control’s separation and centralized control.The controller node is responsible for realizing the route planning and traffic control of the whole network.The research content of this paper mainly aims at the platform building of the system and the key technologies.Our work is as follows:1.We comprehensively analyze the features of the traditional wireless sensor network and related technology,study the key concept of software defined network and implement the design of wireless sensor network architecture based on the concept of centralized control.So we get a new architecture called software defined wireless sensor network(SDWSN).2.We set up a system of the wireless sensor network combined with SDN and realize that the nodes in the network can communicate with each other on multi-hops ways.We use Raspberry Pi as the foundation to design sensor nodes.Then we design SDWSN protocol stack and the network structure,determine the network process and put forward the key algorithm of topology discovery and route distribution.3.We test the algorithm in the actual scene,observe not only the time delay and packet loss rate,but also the survival time of a single node.We compare SDWSN system and the traditional wireless sensor network,verify the improvement of the communication performance.