Recent advances in the blockchain research have been made in two important directions. One is refined resilience analysis utilizing game theory to study the consequences of selfish behaviors of users (miners), and the other is the extension from a linear (chain) structure to a non-linear (graphical) structure for performance improvements, such as IOTA and Graphcoin. The first question that comes to people's minds is what improvements that a blockchain system would see by leveraging these new advances. In this paper, we consider three major metrics for a blockchain system: full verification, scalability, and finality-duration. We { establish a formal framework and} prove that no blockchain system can achieve full verification, high scalability, and low finality-duration simultaneously. We observe that classical blockchain systems like Bitcoin achieves full verification and low finality-duration, Harmony and Ethereum 2.0 achieve low finality-duration and high scalability. As a complementary, we design a non-linear blockchain system that achieves full verification and scalability. We also establish, for the first time, the trade-off between scalability and finality-duration.
翻译:块链研究的最近进展在两个重要方向上已经取得。一个是改进弹性分析,利用游戏理论来研究用户(采矿者)自私行为的后果。另一个是从线性(链)结构向非线性(线性)结构的延伸,以提高性能,如IOTA和Greapocoin。人们认为,第一个问题是块链系统通过利用这些新进展将看到哪些改进。在本文中,我们考虑对块链系统的三大指标:全面核查、可伸缩性和最终性。我们{建立一个正式框架和}证明,任何块链系统都不能同时实现充分核查、高度可伸缩性和低最终性。我们注意到,象Bitcoin这样的典型块链系统能够实现充分核查,而最后性能低、和谐和Eceenum 2.0能够实现低最终性、低最终性能和高度可伸缩性。我们作为补充,我们设计了一个非线性链性系统,以实现全面核查和可伸缩性。我们第一次还建立了贸易性与最终性之间的伸缩性。