The consensus mechanism is the core secret of the blockchain network. However, the consensus mechanism of the classical blockchain is based on the classical cryptosystem, which is based on the problem of computational complexity. With the improvement of computing power, the security of this cryptosystem is being threatened. In addition, the consensus mechanism of classic blockchain also has the following disadvantages: serious waste of computing resources and energy; the inability to withstand a 51% attack; low system throughput and large delay. Based on quantum teleportation technology and the randomness of quantum measurement, a consensus mechanism for a quantum blockchain system is proposed. Based on the physical properties of quantum mechanics, this scheme has the unconditional security of quantum cryptography. This new consensus mechanism does not involve a great deal of computing resources and hence has a lower energy consumption, shorter time delay and higher throughput. Furthermore, the new consensus mechanism could withstand a 51% attack.
The consensus mechanism is the core secret of the blockchain network. However, the consensus mechanism of the classical blockchain is based on the classical cryptosystem, which is based on the problem of computational complexity. With the improvement of computing power, the security of this cryptosystem is being threatened. In addition, the consensus mechanism of classic blockchain also has the following disadvantages: serious waste of computing resources and energy; the inability to withstand a 51% attack; low system throughput and large delay. Based on quantum teleportation technology and the randomness of quantum measurement, a consensus mechanism for a quantum blockchain system is proposed. Based on the physical properties of quantum mechanics, this scheme has the unconditional security of quantum cryptography. This new consensus mechanism does not involve a great deal of computing resources and hence has a lower energy consumption, shorter time delay and higher throughput. Furthermore, the new consensus mechanism could withstand a 51% attack.
Blockchain technology represented by Bitcoin and Ethereum has been deeply developed and widely used due to its broad application prospects such as digital currency and IoT. However, the security of the existing blockchain technologies built on the classical cryptography depends on the computational complexity problem. With the enhancement of the attackers’ computing power, especially the upcoming quantum computers, this kind of security is seriously threatened. Based on quantum hash, quantum SWAP test and quantum teleportation, a quantum blockchain system is proposed with quantum secure communication. In classical cryptographic theory sense, the security of this system is unconditional since it has nothing to do with the attackers’ computing power and computing resources.
This paper investigates the integration of quantum error correction (QEC) techniques with blockchain consensus mechanisms to address inherent vulnerabilities and inefficiencies within traditional blockchain systems. The core claim centers around leveraging QEC's robust error detection and correction capabilities to bolster blockchain security, enhance consensus efficiency, and improve overall scalability. The proposed mechanism utilizes QEC to protect blockchain data from malicious attacks and environmental noise, thereby strengthening the consensus process. Furthermore, the application of QEC can accelerate the consensus algorithm, reducing latency and improving throughput. This work presents a novel approach to blockchain design, moving beyond classical cryptographic methods to incorporate the power of quantum mechanics for a more resilient and performant distributed ledger technology. The paper outlines the theoretical framework, proposes a specific QEC-enhanced consensus protocol, and discusses potential challenges and future research directions. The ultimate goal is to create a blockchain system that is inherently secure against attacks and capable of handling high transaction volumes with minimal delay. ---
Blockchain technology affords data integrity protection and building trust mechanisms in transactions for distributed networks, and, therefore, is seen as a promising revolutionary information technology. At the same time, the ongoing breakthrough in quantum computation technology contributes toward large-scale quantum computers, which might attack classic cryptography, seriously threatening the classic cryptography security currently employed in the blockchain. As a better alternative, a quantum blockchain has high expectations of being immune to quantum computing attacks perpetrated by quantum adversaries. Although several works have been presented, the problems of impracticality and inefficiency in quantum blockchain systems remain prominent and need to be addressed. First, this paper develops a quantum-secure blockchain (QSB) scheme by introducing a consensus mechanism-quantum proof of authority (QPoA) and an identity-based quantum signature (IQS)-wherein QPoA is used for new block generation and IQS is used for transaction signing and verification. Second, QPoA is developed by adopting a quantum voting protocol to achieve secure and efficient decentralization for the blockchain system, and a quantum random number generator (QRNG) is deployed for randomized leader node election to protect the blockchain system from centralized attacks like distributed denial of service (DDoS). Compared to previous work, our scheme is more practical and efficient without sacrificing security, greatly contributing to better addressing the challenges in the quantum era. Extensive security analysis demonstrates that our scheme provides better protection against quantum computing attacks than classic blockchains. Overall, our scheme presents a feasible solution for blockchain systems against quantum computing attacks through a quantum strategy, contributing toward quantum-secured blockchain in the quantum era.
In this era of technological change, metaverse has attracted extensive attention from all over the world as next-generation internet. Blockchain technology plays an indispensable role in realizing the independent digital identity and economic system which are the significant attributes of the metaverse. To achieve the cross-universe mechanism and reduce network resource consumption, this paper proposes a cross-chain protocol for the underlying architecture of metaverse that utilizes an identity information chain to guarantee the separate digital identity of users and decrease the data interaction between varied consortium blockchains. However, along with the rapid development of quantum computing, the classical cryptosystems which commonly count on mathematical complexity will not be reliable and secure. The current post-quantum cryptography technologies that increase the time complexity of algorithm will lead to quite low efficiency and high resource overhead while applying to blockchain structures. But quantum cryptography is capable of lifting both security and efficiency of blockchain. As a result, the scheme put forward in the article adopts quantum teleportation to implement secure communication. In addition, to assure the atomicity of cross-chain transactions that cross-chain asset exchanges succeed or fail simultaneously, a quantum time lock that improves the previous studies and combines quantum cryptography technology is proposed.
The emergence of quantum computing poses a significant threat to the security of traditional blockchain systems, which rely heavily on classical cryptographic algorithms. To safeguard the integrity and reliability of blockchain technology in the upcoming era, this work proposes a novel quantum-resistant blockchain architecture. This approach integrates a robust consensus mechanism, with advanced quantum cryptographic primitives, including quantum digital signatures based on a Quantum Hash Function (QHF). Incorporating a quantum hash function enhances the blockchain resistance, providing an additional layer of security against quantum attacks. By combining these elements, our method creates a blockchain system fortified against the potential vulnerabilities introduced by quantum computers. The proposed solution leverages the power of QHFs to safeguard transaction integrity, while the consensus mechanism ensures the reliability and decentralization of the network. This paper also delves into the theoretical underpinnings of quantum blockchains, exploring their design, feasibility, and potential applications, emphasizing their promising future, particularly in areas such as decentralized identity authentication. Finally, it contributes to the development of a secure and resilient blockchain ecosystem capable of thriving in the coming era.
Quantum blockchain is expected to offer an alternative to classical blockchain to resist malicious attacks laughed by future quantum computers. Although a few quantum blockchain schemes have been constructed, their efficiency is low and unable to meet application requirements due to the fact that they lack of a suitable consensus mechanism. To tackle this issue, a consensus mechanism called quantum delegated proof of stake (QDPoS) is constructed by using quantum voting to provide fast decentralization for the quantum blockchain scheme at first. Then an efficient scheme is proposed for quantum blockchain based on QDPoS, where the classical information is initialized as a part of each single quantum state and these quantum states are entangled to form the chain. Compared with previous methods, the designed quantum blockchain scheme is more complete and carried out with higher efficiency, which greatly contributes to better adapting to the challenges of the quantum era.