PoVF: Empowering Decentralized Blockchain Systems with Verifiable Function Consensus
Chenxi Xiong, Ting Yang, Yu Wang, Bing Dong
TL;DR
PoVF tackles decentralization and efficiency in blockchain consensus by integrating Verifiable Delay Functions and Verifiable Random Functions to ensure fair, unpredictable participation. It introduces a dynamic epoch-based node selection, a VDF-based heartbeat to deter Sybil attacks, and a Delay Buffer to prevent forks, achieving high throughput and strong decentralization. Empirical results show throughput up to about 4000 TPS and a Gini coefficient of 0.39, with robust protection against Sybil, prophecy, and replay attacks. The work demonstrates PoVF as a scalable, secure, and decentralized approach for public blockchains, with clear directions for further refinement of the Delay Buffer, fairness metrics, and time synchronization.
Abstract
Consensus mechanism is the core technology for blockchain to ensure that transactions are executed in sequence. It also determines the decentralization, security, and efficiency of blockchain. Existing mechanisms all have certain centralization issues and fail to ensure the decentralization of blockchain networks. A decentralized and efficient mechanism is required to improve blockchain systems. This paper proposes a fair consensus mechanism called Proof of Verifiable Functions (PoVF), based on the verifiability and unpredictability of verifiable functions. PoVF provides a sufficiently fair mechanism, ensuring that all nodes in blockchain network have equal opportunity to participate in consensus. In addition, a structure called "Delay buffer" is proposed to ensure transactions are executed sequentially. It delay the selection of blocks to avoid blockchain forks caused by broadcasting and transaction execution confusion. According to our security analysis, PoVF is provably secure and has the ability to resist potential adversaries. According to the experiments, PoVF-based blockchain can process up to 4000 transactions per second with nodes configured with only 4-core CPUs. This paper uses the Gini coefficient to measure the decentralization of blockchains, and the PoVF-based blockchain achieves the lowest Gini coefficient of 0.39 among all sampled blockchains. PoVF has been shown to provide sufficient efficiency while ensuring decentralization and security through experiments.