A Review on Double Spending Problem in Blockchain

The double-spending problem in blockchain technology is a significant challenge that threatens the integrity and trustworthiness of decentralized systems. This problem occurs when a user attempts to spend the same cryptocurrency unit twice, leading to a situation where the blockchain network must decide which transaction to accept and which to reject. One of the most urgent problems with blockchain technology is the issue of double spending, as it undermines the fundamental principles of trust and transparency that underlie decentralized systems. Various factors can contribute to the double-spending problem, including network latency, malicious actors, and the consensus mechanism used to validate transactions. This study investigates the many approaches put out to solve the double-spending issue in blockchain technology. The proof-of-work consensus mechanism, which necessitates network users to carry out difficult calculations in order to validate transactions, is one of the most popular alternatives. The proof-of-stake consensus technique is an additional remedy, which relies on participants staking their cryptocurrency units to validate transactions. While both mechanisms have their advantages and disadvantages, they are not foolproof and can be vulnerable to attacks. Emerging technologies, like multi-party computation and zero-knowledge proofs, are being investigated in addition to current solutions to the double-spending issue. Overall, this paper highlights the critical nature of the double-spending problem in blockchain technology and evaluates the existing and emerging solutions to the issue.