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.
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.
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.
As a popular decentralized and distributed database exhibiting transparency and unforgeability, blockchain has received widespread attention. At the time of writing, its security hinges on classical cryptography, which maintains a high grade of security by exploiting the potentially excessive computational complexity of mathematical problems to be solved by state-of-the-art computers. However, as computational technology develops, this encryption philosophy is likely to be challenged and there is a risk of ’store now and decrypt later’ attacks. A compelling solution to this security threat is to intrinsically integrate blockchain with quantum technology. Against this background, we propose a quantum blockchain scheme relying on quantum secure direct communication (QSDC). Specifically, we conceive QSDC-based blockchain for identity verification, message encryption, and consensus. We also propose an optical network based realization of the proposed QSDC-aided blockchain using present-day technology. Our simulations quantify the benefits of the scheme, especially in terms of its resource utilization. This work provides a new prospect for the intrinsic fusion of quantum information technology and blockchain technology, paving the way for its rapid commercialization.
Rapid growth in IoT devices creates major security difficulties because they present potential weakening of systems to cyberattacks and open data breaches in addition to unauthorized system access. Traditional security methods relying on centralized authentication together with classical cryptographic techniques prove inadequate because they have single points of failure and exist under the threat of quantum computing advancement. A new system integrates blockchain technology and quantum cryptography according to this paper to resolve security issues. Data security through blockchain systems gives access to decentralized trust features together with tamper-proof records and ensures data integrity while quantum cryptographic methods especially Quantum Key Distribution (QKD) enable unconditional cryptographic key transfers and communications. A proposed security framework protects IoT networks through the integration of blockchain's unalterable system and QKD's quantum-resistant capabilities which create a strong defence system against classical and quantum-based threats. The approach includes three primary achievements: a system design that scales and performs security analyses together with performance tests that prove practicality. The presented research enables the development of next-generation IoT security measures suited for modern quantum technology advancements.
Quantum computing's development poses a significant threat to the cryptographic security of current blockchain technologies, potentially undermining the integrity of digital transactions. Quantum computers can break the complex mathematical problems that algorithms like RSA and ECC rely on, which could lead to vulnerabilities such as double-spending and fraud. To address these risks, the blockchain community is exploring quantum-resistant protocols that employ post-quantum cryptographic algorithms, which are designed to withstand quantum computing attacks. Quantum-secure blockchain protocols integrate quantum key distribution (QKD) and post-quantum cryptography (PQC) to enhance security. QKD uses quantum mechanics principles to secure communication channels, ensuring that any attempt to intercept the key introduces detectable anomalies. PQC involves algorithms like lattice-based, hash-based, or multivariate polynomial-based algorithms that are believed to be secure against quantum attacks. These protocols aim to maintain the confidentiality, integrity, and security of data transmitted over the blockchain, ensuring the longevity and reliability of blockchain systems in the face of evolving computational advancements. A quantum-secure blockchain scheme (QSB) utilizes a consensus mechanism, QPoA, and IQS. The QPoA is leveraged for block generation while the IQS is deployed in transaction verification1. Furthermore, the integration of quantum computing with blockchain can address current limitations, such as slow transaction speeds and lack of scalability, by optimizing calculations and enabling smarter, more sophisticated smart contracts. The development and implementation of quantum-resistant blockchains are essential for future-proofing digital transactions and maintaining trust in decentralized systems
Abstract Blockchain technology is a highly developed database system that shares information within a business web. It stores details in blocks connected chronologically, ensuring information integrity through consensus mechanisms that prevent unauthorised alterations. This decentralised system removes the need for a believable mediator, mitigating vulnerabilities and enhancing transaction security. Blockchain’s application spans the energy, finance, media, entertainment, and retail sectors. However, classical blockchain faces threats from quantum computing advancements, necessitating the development of quantum blockchain technology. Quantum blockchain, leveraging quantum computation and information theory, offers enhanced security and immutability. In this paper, different mathematical foundations, practical implementations and effectiveness of lattice‐based cryptography in securing blockchain applications are discussed. Analysis of how the cryptographic techniques can protect blockchain systems against quantum attacks is being done by using mathematical formulations and examples. Quantum computing strengthens blockchain security with advanced encryption and authentication, which is critical for safeguarding diverse sectors from evolving cyber threats. Further study on quantum‐resistant design is necessary if blockchain networks are to be robust and intact in the face of future technological developments.
Blockchain (BC) as a distributed ledger technology is getting more and more recognition in modern network technologies that are moving away from centralized toward decentralized management. However, the blockchain’s security is built on the computational complexity of certain mathematical problems that cannot be solved on existing “classical” computers in an acceptable time. Nevertheless, quantum computers have the capability to effortlessly solve such problems with a significant reduction in time. The current blockchain technology relies on two main computational constructions; digital signatures and cryptographic hash functions. Both of them are threatened by the quantum computers. In this work, we report on the quantum threats to “classical” blockchain technology. The main directions to produce quantum-resistant blockchain (QB) platforms are reviewed with an emphasis on approaches based on Quantum Key Distribution (QKD). Then, some notable challenges in implementing QBs are discussed. Indeed, the future research directions in this field are identified.