AbstractData security has become a growing concern for individuals, businesses, and governments because of increasing cyberattacks, data tampering, and unauthorized access in centralized systems. According to the National Institute of Standards and Technology, blockchain technology addresses these challenges by providing a tamper-evident and tamper-resistant distributed ledger that is implemented without a central authority and records transactions across multiple computers. Its decentralized structure eliminates reliance on a single authority, reducing the risk of system failures and targeted attacks. This Article reviews core blockchain security features, including cryptographic protection, decentralization, consensus mechanisms, immutability, transparency, and smart contract security. Cryptographic tools such as hashing and public-private key systems protect data confidentiality, ensure integrity, and verify user identities. Consensus models like Proof of Work, Proof of Stake, and Practical Byzantine Fault Tolerance enable secure transaction validation. The immutability of blockchain records makes unauthorized changes difficult, supporting trust and auditability. The study also examines threats such as 51% attacks, Sybil attacks, private key theft, and smart contract vulnerabilities, and recommends security practices to mitigate these risks. Finally, the Article explores blockchain applications in healthcare, banking, supply chains, voting, and digital identity. The findings indicate that, despite technical and operational challenges, blockchain offers a promising approach to securing digital transactions, protecting sensitive data, and building trust in the digital environment.
Amit Shrivastava (2026) studied this question.