Research On Lightweight Consensus Mechanism Of Blockchain For Internet Of Things

In recent years,with the development of mobile networks and intelligent devices,the Internet of things has developed rapidly.More and more intelligent applications based on the Internet of things are emerging.Highly interconnected intelligent devices and the large amount of transaction data generated by them have aroused the concern of security and privacy.As a new distributed computing framework,blockchain has the characteristics of decentralization,non tampering,traceability and so on.It is widely used in various fields such as finance,electronic forensics,commodity traceability and so on.The application of blockchain in the field of Internet of things has just begun.However,the existing blockchain platforms,including bitcoin,Ethereum and super ledger,have high computing overhead,which mainly comes from the consensus mechanism.For example,in the workload proof mechanism of bitcoin system,a lot of computing power is needed to maintain the bitcoin transaction ledger.In the Internet of things,the computing power and storage capacity of nodes are generally low,and the nodes are highly heterogeneous and dynamic.These problems make the existing blockchain system unable to be deployed in the Internet of things environment.Therefore,how to design a lightweight consensus algorithm so that blockchain technology can be applied to the Internet of things environment is a very important problem.Aiming at the above problems,this paper designs a consensus mechanism of lightweight blockchain for the Internet of things.On the basis of summarizing the relevant research at home and abroad,this paper first designs the application model of blockchain in the Internet of things,which includes three layers: low resource node layer,high resource node layer and cloud storage layer.In this three-tier model,the network is divided into multiple clusters,each cluster contains a high resource node and multiple low resource nodes.Low resource nodes generate transaction data,while high resource nodes participate in the consensus process of blockchain;The cloud storage layer is used to store the generated blockchain data,that is,distributed ledger.Secondly,this paper designs a lightweight blockchain consensus algorithm based on credit value.Based on node credit value and proof of rights and interests,the algorithm can quickly elect nodes qualified to pack blocks to produce new blocks,and realize the consensus algorithm of lightweight blockchain in the environment of Internet of things.Finally,this paper simulates and implements the blockchain in the Internet of things environment on Contiki / cooja platform,and evaluates the transactions generated by low resource nodes;High resource nodes participate in the simulation architecture of blockchain lightweight consensus algorithm based on credit value,and the energy consumption of two types of nodes is low.Compared with the CPU energy consumption of the standard IPv6 client / server simulation architecture on Contiki platform,the CPU energy consumption of high resource nodes is higher than that of IPv6 server nodes,but not much higher than that of IPv6 server nodes.The energy consumption of low resource node is slightly higher than that of IPv6 customer service node.The experimental results show that the model of IOT blockchain based on credit value lightweight consensus algorithm designed in this paper is superior to the existing classic blockchain with huge energy consumption in terms of energy consumption.