Design And Implementation Of Routing Mechanism For SDWSN

As the technologies of information processing such as 'big data,cloud computing are becoming more and more mature,people's desire of access to information becomes more urgent.Sensor data is just an important kind of the source of information.In recent years,several home appliance manufacturers fight for the market of home wireless sensor network with the concept of "smart home",which brings great changes to people's lives.Wireless sensor network,with its simple layout and flexible networking,has great potential in the wave of data technology development.However,problems such as poor scalability and lack of collaborative perception also gradually exposed.For this reason,academics propose the concept of Software Defined Wireless Sensor Network(SDWSN),combining centralized control and traditional wireless sensor network,to realize the network programmability,adapt to the various application requirements.First,this paper summarizes the existing research results.Then,a centralized control routing mechanism for Software Defined Wireless Sensor Networks is proposed,combined with load balancing algorithms.Through the centralized network topology discovery mechanism,the entire network topology is collected at the controller.The routing rules are calculated based on the topology information and delivered to each sensor node.So that the entire network routing can be established and the load balancing routing planning can be achieved.In order to improve this mechanism,topology maintenance mechanism is designed to make sure that the controller can detect network topology changes in time and adjust routing strategies.Besides,the design of link quality assessment method can not only tolerate a certain degree of fluctuation,but also track the change as soon as possible.In this way,the control messages in the network can be simplified.On the one hand to reduce the risk of loss of control messages,on the other hand to reduce control overhead and optimize system performance.This mechanism can simplify the computing requirements of sensing nodes and reduce energy consumption and cost.The controller centrally controls all nodes,can flexibly configure routing policies and node status.Collaborative perception and overall layout enhance system's robustness and scalability.The feasibility of this mechanism is verified by simulation.The mechanism can realize the expected function on the SDWSN system we implemented.At last,we test the mechanism.By analysis of test results,the routing mechanism is verified the ability of centralized management of the network topology and routing optimization selection and automatic repair.Adding load-balancing algorithms makes this mechanism perform well in packet loss rate and maximum bandwidth test.A link with 8 hops gets 10%packet loss rate and its maximum bandwidth is 8Mbits/s.