Research On The Application Of Quantum Information Technology In Blockchains

Blockchain is a tamper-evident,open and transparent distributed ledger maintained by all nodes in a peer-to-peer network.It is an integration of multiple technologies,including distributed technologies,cryptography,and consensus mechanisms.Since blockchain supports peer-to-peer transaction systems that eliminate trusted third parties,it has been widely used in many fields.However,quantum computing has caused a huge impact on classical cryptography with its advantage of having arithmetic power unmatched by classical computing,which means that the security of blockchain is facing a serious challenge.Because the data structure of blockchain and the transactions in it need to be secured by the hash functions and digital signatures in classical cryptography.How to ensure that the blockchain can adapt to the quantum era has become an important research topic.The quantum information technology such as quantum communication and quantum cryptography based on the principle of quantum mechanics can be used to protect the security of information.Combining quantum information technology and blockchain to realize a secure blockchain solution has broad prospects.The purpose of this paper is to apply quantum information technology to blockchain to improve the security of blockchain.To address the problem of quantum attacks on blockchain,the research on the application of quantum information technology in blockchain is mainly carried out in two aspects.1.In response to the problem that quantum computers make the consensus mechanism unfair due to the imbalance of nodes’ arithmetic power in blockchain,the quantum delegated proof-of-stake(Q-DPo S)consensus mechanism is designed based on the quantum voting protocol to provide an efficient and secure consensus method for blockchain.In a blockchain using Q-DPo S,nodes do not rely on hashrate to compete for the bookkeeping rights of blocks,but instead perform quantum voting through shared quantum entanglement states to elect representative nodes to be responsible for block generation.As well as the security of the quantum voting protocol in Q-DPo S is based on quantum mechanics principles rather than mathematical hard problems,which can ensure that Q-DPo S is well protected against the impact of quantum computers in the voting phase.As well as the security of the quantum voting protocol in Q-DPo S is based on quantum mechanics principles rather than mathematical hard problems,which can ensure that Q-DPo S is well protected against the impact of quantum computers in the voting phase.Meanwhile,problems such as the proof-of-work consensus mechanism’s principle relying on computational hash functions leading to the possibility of some groups monopolizing the blockchain’s bookkeeping rights with the augmentation of quantum computers are solved.The Q-DPo S consensus mechanism combines quantum information technology and classical consensus mechanism to provide secure consensus function for blockchain.2.A new quantum blockchain scheme is proposed by combining quantum digital signature with the designed Q-DPo S consensus mechanism.In this scheme,the quantum blockchain data structure is constructed by designing quantum blocks with a single quantum bit,and the quantum blocks are linked with each other by quantum entanglement to form a chain.After the transaction information is verified by quantum digital signature,it is loaded onto the quantum block by quantum rotation operation in the form of phase.The bookkeeping right of the quantum block is determined by the Q-DPo S consensus mechanism.The scheme replaces classical digital signatures and hash functions with quantum digital signatures and quantum entanglement principles,and provides efficient decentralization using the Q-DPo S consensus mechanism.The security analysis of the scheme shows that the scheme is resistant to attacks on the blockchain by quantum computers.And it is more efficient compared to other quantum blockchain schemes,which can better cope with the challenges to blockchain in the quantum era.