New Challenges and its Security, Privacy Aspects on Blockchain Systems

Decentralization, autonomy, integrity, immutability, verification, fault-tolerance, anonymity, auditability, and transparency are all desirable qualities in a technology, and all of them are present in blockchain. In this paper, we first conduct a more indepth survey of blockchain technology, focusing on its origins, the quantitative comparisons of consensus algorithms, the specifics of the cryptography employed by the blockchain (including public key cryptography, Zero-Knowledge Proofs, and hash functions), and exhaustive list of use cases for blockchain technology. In addition, this study concentrates on blockchain security issues. In this paper, we use a risk-based approach to evaluate blockchain security, classify the various threats to the network, dissect actual attacks and vulnerabilities, and round up the most recent blockchain security solutions. Finally, the difficulties and future directions of research to improve the scalability and security of blockchain systems for largescale deployments are discussed.