Research And Implementation Of Key Technologies For 6LoWPAN Access To IPv4 Network Border Routing

With the development of society and the advancement of science and technology,the requirements for the integration of wireless sensor networks(WSNs)into the Internet are becoming more and more urgent.Driven by this requirement,the introduction of IPv6 technology planned in the network into the WSNs came into being.However,the dominant IPv4 network in the Internet is still unable to be shaken.IPv6 is only a plan,and the transition to it will be a slow process.IPv6-based WSNs cannot communicate with IPv4 networks directly at this stage,and the interconnection of heterogeneous networks must be resolved.In addition,due to the vulnerability of WSNs,it is easily affected by the non-deterministic factors in the application environment.For nodes that have already been deployed,the information collected after being interfered cannot reflect the environmental conditions at that time,and the nodes can be trusted.The degree will be greatly reduced.In order to improve the reliability of the sensor system,it is necessary to solve the problem of node data reliability.(1)For IPv6-based 6LoWPAN(6LoWPAN)and Internet(IPv4)networks cannot communicate with each other due to network layer protocol differences,this thesis designs a border gateway based on which IPv6 sensor network packets and IPv4 packets are used for information conversion.According to the 6LoWPAN standard communication protocol,the adapter layer defined in the 6LoWPAN protocol stack is omitted during the conversion process,so that the 6LoWPAN sensor network can efficiently communicate with the IPv4 network.(2)Aiming at the reliability of sensor node data in WSNs,this thesis proposes a measurement scheme based on BP neural network to judge the credibility of node data.The solution is deployed in gateways that interoperate between WSNs and IPv4 networks.It uses the different types of environmental data collected by the nodes as different attributes of the node's credibility.The credibility of these attributes is obtained by verifying the credibility of these attributes.The credibility value makes the corresponding operation.(3)Based on the design of this thesis,the 6LoWPAN access gateway,address and protocol conversion mechanism,gateway access to IPv4 network,and system performance are tested in the interworking of messages.The results show that the gateway system designed in this thesis can interconnect 6LoWPAN and IPv4 and provide real-time information monitoring data to the data center.In the node data credibility scheme,based on the environment data collected under real conditions,a simulation experiment was conducted on the credibility evaluation scheme designed in this thesis.Through experiments,we conclude that the scheme can effectively provide the degree of credibility of the system to the nodes when the WSNs are interfered by different degrees under different scales and perform corresponding operations according to the values.