Research On Consensus Mechanism For Blockchain Integrated Iot

With the continuous development and maturity of microchip,communication technology and computer network technology,the Internet of things(IoT)technology has gradually developed from the initial concept into an important part of the new generation of information technology,and the Internet of things industry has developed rapidly all over the world.Meanwhile,since blockchain technology can provide an immutable and traceable form of data that would be used across a peer-to-peer network,blockchain is proposed to provide security protection for IoT,to ensure the security of information storage,transactions and communication,which has become a research hotspot in the field of IoT and blockchain technology.Nonetheless,due to some aspects of IoT,such as resource-constrained devices,heterogeneous mass devices,and real-time transactions,the traditional blockchain consensus algorithm is not suitable for the scene of blockchain-IoT integration.Two classic consensus mechanisms are considered:1)the proof-of-work(PoW)consensus needs resource-intensive devices,has low transaction throughputs and low access security,which does not meet the resource limitation of IoT devices,large volume of transaction data and high real-time requirements,and high access security requirements;2)the Practical Byzantine Fault Tolerance(PBFT)is not suitable for the fair and transparent application scenarios of IoT,and cannot achieve high performance on a large scale since the control of the blockchain is concentrated on a few nodes,and the performance of PBFT would degrade dramatically as the number of nodes participating in the consensus increases.Regarding those problems above,this thesis proposes a role based framework design(BlockloT)for the blockchain integrated with IoT,as well as a dual vote confirmation based consensus(DVCC)mechanism for BlockIoT.In BlockIoT,we adopt a role division approach to solve the problem of limited resources of devices in IoT.Devices in different layers of IoT are assigned to play different roles in the blockchain according to their different capacities and needs.In DVCC,multi-dimensional credit score,dual confirmation mechanism,classified random selection mechanism,and credit score based incentivization are designed to improve the security and fairness of the consensus.In addition,a voting mechanism is proposed to improve the delay performance and avoid energy waste.Finally,this thesis makes a simulation analysis on the security,consensus latency and throughput performance of DVCC,and the simulation results show that the proposed DVCC can be effectively applied to the the scene of blockchain-IoT integration.Compared with PoW mechanism,DVCC has the advantages of low energy consumption and high efficiency.Compared with PBFT mechanism,DVCC can realize low delay and high throughput of multi-node participation while guaranteeing the security and fairness of the consensus..