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462 results · page 13 of 20
Sweta Gupta, Aparna Gupta, Ishan Y. Pandya, Abhishek Bhatt · 5 authors
No abstract is available for this record.
Te-Yuan Lin, Chiou‐Shann Fuh
Quantum computing is no longer a thing of the future. Shor’s algorithm proved that a quantum computer couldtraverse key of factoring problems in polynomial time. Because the time-complexity of the exhaustive keysearch for quantum computing has not reliably exceeded the reasonable expiry of crypto key validity, it is believedthat current cryptography systems built on top of computational security are not quantum-safe. Quantumkey distribution fundamentally solves the problem of eavesdropping; nevertheless, it requires quantumpreparatory work and quantum-network infrastructure, and these remain unrealistic with classical computers.In transitioning to a mature quantum world, developing a quantum-resistant mechanism becomes a stringentproblem. In this research, we innovatively tackled this challenge using a non-computational difficulty schemewith zero-knowledge proof in order to achieve repellency against quantum computing cryptanalysis attacks foruniversal classical clients.
Marcos Allende, Diego López León, Sergio Cerón, Adrián Pareja · 14 authors
The advent of quantum computing threatens blockchain protocols and networks because they utilize non-quantum resistant cryptographic algorithms. When quantum computers become robust enough to run Shor's algorithm on a large scale, the most used asymmetric algorithms, utilized for digital signatures and message encryption, such as RSA, (EC)DSA, and (EC)DH, will be no longer secure. Quantum computers will be able to break them within a short period of time. Similarly, Grover's algorithm concedes a quadratic advantage for mining blocks in certain consensus protocols such as proof of work. Today, there are hundreds of billions of dollars denominated in cryptocurrencies and other digital assets that rely on blockchain ledgers as well as thousands of blockchain-based applications storing value in blockchain networks. Cryptocurrencies and blockchain-based applications require solutions that guarantee quantum resistance in order to preserve the integrity of data and assets in these public and immutable ledgers. The quantum threat and some potential solutions are well understood and presented in the literature. However, most proposals are theoretical, require large QKD networks, or propose new quantum-resistant blockchain networks to be built from scratch. Our work, which is presented in this paper, is pioneer in proposing an end-to-end framework for post-quantum blockchain networks that can be applied to existing blockchain to achieve quantum-resistance. We have developed an open-source implementation in an Ethereum-based (i.e., EVM compatible) network that can be extended to other existing blockchains. For the implementation we have (i) used quantum entropy to generate post-quantum key pairs, (ii) established post-quantum TLS connections and X.509 certificates to secure the exchange of information between blockchain nodes over the internet without needing a large QKD network, (iii) introduced a post-quantum second signature in transactions using Falcon-512 post-quantum keys, and (iv) developed the first on-chain verification of post-quantum signatures using three different mechanisms that are compared and analyzed: Solidity smart-contracts run by the validators for each transaction, modified EVM Opcode, and precompiled smart contracts.
Xiaojun Wen, Yongzhi Chen, Xincan Fan, Zhengzhong Yi · 6 authors
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.
Dan A. Bard, Joseph J. Kearney, Carlos A. Pérez-Delgado
Proof-of-Work (PoW) is a fundamental underlying technology behind most major blockchain cryptocurrencies. It has been previously pointed out that quantum devices provide a computational advantage in performing PoW in the context of Bitcoin. Here we make the case that this quantum advantage extends not only to all existing PoW mechanisms, but to any possible PoW as well. This has strong consequences regarding both quantum-based attacks on the integrity of the entirety of the blockchain, as well as more legitimate uses of quantum computation for the purpose of mining Bitcoin and other cryptocurrencies. For the first case, we estimate when these quantum attacks will become feasible, for various cryptocurrencies, and discuss the impact of such attacks. For the latter, we derive a precise formula to calculate the economic incentive for switching to quantum-based cryptocurrency miners. Using this formula, we analyze several test scenarios, and conclude that investing in quantum hardware for cryptocurrency mining has the potential to pay off immensely.
V Vignesh, S. Harihara Gopalan, M.S. Kiran Mohan, R S Ramya · 5 authors
Abstract Protection measures are essential to present day blockchain innovation ever, since they can exist short of empowered outsider, which implies that there may not be a disclosed trustworthy individual or group responsible for frameworks. Security of the present frameworks depends on estimating the firmness assumptions and large numbers of the benchmark cryptographic functions proven to be powerless for crucial monetary and a variety of applications against the approach of undeniable quantum machines. Upgrading blockchain innovation with the future of quantum states in a shared manner will enhance the degree of protection and security by-laws of physical science, which is never feasible from non-quantum data hypothetical perspectives. In this article, we propose a quantum-built way to deal with harness of security for a democratic application with the execution, utilizing Hyperledger Sawtooth.
Xiang-lin Gou, Runhua Shi, Wei Gao, Mingxia Wu
No abstract is available for this record.
Saeed Banaeian Far, Maryam Rajabzadeh Asaar
No abstract is available for this record.
Hussein Abulkasim, Atefeh Mashatan, Shohini Ghose
No abstract is available for this record.
Gerardo Iovane
In this work, we propose a new protocol for data transmission, using both the potential of quantum encryption expressed by the BB84 protocol and the possibilities offered by distributed ledgers and blockchain. As we shall see, this approach allows the transmission of keys in maximum security whether it is owned in quantum communication channel, or by using traditional channel and emulating on it a quantum functionalization thanks to the use of network nodes as new virtual quantum components, called i) Quantum Spin Generator (QSG), ii) Base Generator (BG), iii) Quantum Photon Polarizer (QPP), iv) Quantum Photon Meter (QPM), v) Quantum Photon Collider (QPC). The end result will be the security of one time pad encryption and quantum encryption, an intrinsic crypto agility linked to the dynamic allocation and functionalization of nodes, a growing security proportional to the growth of the number of network nodes used to encrypt and transmit the information.
Bengang Li, Faguo Wu
Blockchain is a very important technology and financial innovation since the birth of the Internet. It is an innovative and integrated application of many technologies, with the characteristics of open and transparent data, not easy to tamper with, easy to trace and so on. Its cryptographic security relies on asymmetric cryptography, such as ECC, RSA. However, with the surprising development of quantum technology, asymmetric cryptography schemes mentioned above would become vulnerable. Recently, some lattice-based blockchain systems have been proposed to be secure against attacks in the quantum era. Although these schemes have theoretical significance, it is unpractical in actual situation due to handling capacity. In this paper, aiming at tackling the critical issue of throughput, we proposed post quantum blockchain with segregation witness which can effectively the proportion of signatures in block size. Based on the hardness assumption of Short Integer Solution (SIS), we demonstrate that the proposed post quantum blockchain with segregation witness existential unforgeability against adaptive chosen-message attacks in the random oracle. As compared to the existing scheme, our scheme has better performance in handling capacity. As the underlying lattice problem is intractable even for quantum computers, our scheme would work well in the quantum age.
Joseph J. Kearney, Carlos A. Perez-Delgado
Quantum computation represents a threat to many cryptographic protocols in operation today. It has been estimated that by 2035, there will exist a quantum computer capable of breaking the vital cryptographic scheme RSA2048. Blockchain technologies rely on cryptographic protocols for many of their essential sub-routines. Some of these protocols, but not all, are open to quantum attacks. Here we analyze the major blockchain-based cryptocurrencies deployed today -- including Bitcoin, Ethereum, Litecoin and ZCash, and determine their risk exposure to quantum attacks. We finish with a comparative analysis of the studied cryptocurrencies and their underlying blockchain technologies and their relative levels of vulnerability to quantum attacks.
Léo Colisson, Frédéric Grosshans, Elham Kashefi
We propose the first generalization of the famous Non-Interactive Zero-Knowledge (NIZK) proofs to quantum languages (NIZKoQS) and we provide a protocol to prove advanced properties on a received quantum state non-destructively and non-interactively (a single message being sent from the prover to the verifier). In our second orthogonal contribution, we improve the costly Remote State Preparation protocols [Cojocaru et al. 2019 ; Gheorghiu and Vidick 2019 ] that can classically fake a quantum channel (this is at the heart of our NIZKoQS protocol) by showing how to create a multi-qubit state from a single superposition. Finally, we generalize these results to a multi-party setting and prove that multiple parties can anonymously distribute a GHZ state in such a way that only participants knowing a secret credential can share this state, which could have applications to quantum anonymous transmission, quantum secret sharing, quantum onion routing and more.
Léo Colisson, Frédéric Grosshans, Elham Kashefi
We propose the first generalization of the famous Non-Interactive\nZero-Knowledge (NIZK) proofs to quantum languages (NIZKoQS) and we provide a\nprotocol to prove advanced properties on a received quantum state\nnon-destructively and non-interactively (a single message being sent from the\nprover to the verifier).\n In our second orthogonal contribution, we improve the costly Remote State\nPreparation protocols [CCKW18,CCKW19,GV19] that can classically fake a quantum\nchannel (this is at the heart of our NIZKoQS protocol) by showing how to create\na multi-qubits state from a single superposition.\n Finally, we generalize these results to a multi-party setting and prove that\nmultiple parties can anonymously distribute a GHZ state in such a way that only\nparticipants knowing a secret credential can share this state, which could have\napplications to quantum anonymous transmission, quantum secret sharing, quantum\nonion routing and more.\n
S. Banupriya, Kottilingam Kottursamy, Ali Kashif Bashir
No abstract is available for this record.
Zhwan Mohammed Khalid, Shavan Askar
Due to the need to maintain confidentiality, redundancy, and openness, the usage of Blockchain and other DLTs has dramatically advanced in recent years, and is being recommended for various applications. In blockchain, these capabilities are supplied by means of hash functions and public-key encryption. However, the rapid development of quantum computation in the near future has opened the door to the Grover and Shor algorithms. These algorithms challenge both public and hash encryption, causing blockchains to redesign and use quantum attack-tolerant cryptosystems; this produces cryptosystems which are considered post-quantum cryptosystems, which are quantum-resistant. This paper reviews current scientists on quantum blockchain for such purposes. In addition, the major challenges are studied with the most important post-quantum blockchain systems. In addition, the most promising post quantum signature encryption and digital blockchain signature schemes are detailed in terms of the functionality and durability of the most promising public signatures. In this article, researchers and developers in blockchain have an extensive perspective and practical advice on post-quantum blockchain protection.
Hyoungsung Kim, Jaehyuk Jang, Sangjun Park, Heung-No Lee
The error-correction code based proof-of-work (ECCPoW) algorithm is based on a low-density parity-check (LDPC) code. The ECCPoW is possible to impair ASIC with its time-varying capability of the parameters of LDPC code. Previous researches on the ECCPoW algorithm have presented its theory and implementation on Bitcoin. But they do not discuss how stable the block generation time is. A finite mean block generation time (BGT) and none heavy-tail BGT distribution are the ones of the focus in this study. In the ECCPoW algorithm, BGT may show a long-tailed distribution due to time-varying cryptographic puzzles. Thus, it is of interest to see if the BGT distribution is not heavy-tailed and if it shows a finite mean. If the distribution is heavy-tailed, then confirmation of a transaction cannot be guaranteed. We present implementation, simulation, and validation of ECCPoW Ethereum. In implementation, we explain how the ECCPoW algorithm is integrated into Ethereum 1.0 as a new consensus algorithm. In the simulation, we perform a multinode simulation to show that the ECCPoW Ethereum works well with automatic difficulty change. In the validation, we present the statistical results of the two-sample Anderson-Darling test to show that the distribution of BGT satisfies the necessary condition of the exponential distribution. Our implementation is downloadable at https://github.com/cryptoecc/ETH-ECC.
Raj Badhwar
No abstract is available for this record.
Masashi Sato
No abstract is available for this record.
Gerardo Iovane
In this paper, we introduce a new approach to fix the validation of a block and the assignment of a new block in a blockchain infrastructure by using a novel negotiation procedure. The block validation and assignment are reached thanks to negotiation procedures based on an extended probability environment. Also, by using a multiscale approach (typical of Complexity Theory) and Quantum and Relativistic Mechanics, the result appears to solve some of the most relevant questions in the Blockchain context, which are the democracy and the randomness of the validator of a block and the assignment of the new one. The selection of actors to mine is invariant concerning the number of addresses, i.e., the coins of owners, which have more chance to be selected generally. This work is the companion of CQKD (Computational Quantum Key Distribution), as we will see in the introduction, where we considered the infrastructural question of the key distribution; also, it is a very effective application of the decision and reasoning in incompleteness or uncertainty conditions as described in the previous and prodromic paper as described in the introduction too.
Nir Bitansky, Zvika Brakerski
No abstract is available for this record.
Teik Guan Tan, Jianying Zhou
No abstract is available for this record.
Brian Haney, Archie Chaudhury
This White Paper introduces and contributes the first implementation of the Decentralized Voting Algorithm. First, Part I provides an overview for the software structures relevant to this work. Second, Part II introduces a decentralized voting algorithm for transferring value on blockchain networks. Third, Part III explains the voting algorithm’s implementation in reach, including the backend architecture, web deployment, and quantum integration. Perhaps most significantly, this paper solves the Decentralized Voting Problem with a new quantum consensus system.
Stephen Holmes, Liqun Chen
No abstract is available for this record.