A Unified Analytical model for proof-of-X schemes. Issue 96 (September 2020)

• Record Type: Journal Article
• Authors: Yu, Guangsheng; Zha, Xuan; Wang, Xu; Ni, Wei; Yu, Kan; Zhang, J. Andrew; Liu, Ren Ping
• Is Part Of: Computers & security. Issue 96(2020)
• Publication Date: 2020-09
• Subjects: Blockchain -- Consensus -- Nakamoto protocol -- Proof-of-X schemes -- Markov chain; Computer security -- Periodicals; Electronic data processing departments -- Security measures -- Periodicals; 005.805
• DOI: 10.1016/j.cose.2020.101934
• Languages: English
• ISSNs: 0167-4048

Abstract

Abstract: Nakamoto protocol, practically solving the Byzantine Generals Problem, can support a variety of proof-based consensus engines, referred to as Proof-of-X (PoX) in permissionless Blockchains. However, there has been to date in lack of a general approach for each miner to evaluate its steady-state profit against the competitors. This paper presents a Markov model which captures explicitly the weighted resource distribution of PoX schemes in large-scale networks and unifies the analysis of different PoX schemes. The new model leads to the development of three new unified metrics for the evaluation, namely, Resource Sensitivity, System Convergence, and Resource Fairness, accounting for security, stability, and fairness, respectively. The generality and applicability of our model are validated by simulation results, revealing that among typically non-Fairness-oriented PoX schemes (such as Proof-of-Work (PoW) and Proof-of-Stake (PoS)), the strongly restricted coinage-based PoS with a Pareto-distributed resource can offer the best performance on Resource Sensitivity, while Proof-of-Publication (PoP) with normal-distributed resource performs the best on System Convergence . Our simulations also reveal the important role of carefully designed Resource Fairness parameter in balancing Resource Sensitivity and System Convergence and improving the performance compared with other non-Fairness-oriented PoX schemes.