A Study of New Micropayment Scheme for Blockchain

Cryptocurrencies based on blockchain infrastructures have shown their advantages such as double-spending resistance and decentralization. Each transaction of cryptocurrency requires a certain amount of computation and attracts transaction fees. Often, in practice, many transactions are small; therefore, they add computation and transmission overheads to the system. In this paper, we introduce a cost-saving approach, which significantly reduces transaction time and storage for small amount of payment, i.e. micropayment. Micropayment means the value of transaction is small, i.e., payment worths a few pennies. To achieve instant micropayments, Hearn and Spilman introduced a notion of payment channel. In this paper, we formally discuss the robustness requirements of a scheme that is suitable for micropayments, consider the explicit value of penalty and user privacy leakage. More precisely, we propose a micropayments scheme for decentralized blockchain-based payment system based on the notion of payment channel, which enables a payee to receive funds at several unsynchronized points of sale and penalize the double-spenders, with instant confirmation. In our approach, with the notion of ‘transaction commitment’, the computation of each transaction is much more efficient. Therefore, our approach has advantages in comparison of other cryptocurrency systems such as the bitcoin system. Our approach can be applied to other existing cryptocurrency systems.