{"title":"Expected linear round synchronization: the missing link for linear Byzantine SMR","authors":"Oded Naor, Idit Keidar","doi":"10.1007/s00446-023-00459-9","DOIUrl":null,"url":null,"abstract":"<p>State Machine Replication (SMR) solutions often divide time into rounds, with a designated leader driving decisions in each round. Progress is guaranteed once all correct processes <i>synchronize</i> to the same round, and the leader of that round is correct. Recently suggested Byzantine SMR solutions such as HotStuff, and LibraBFT achieve progress with a linear message complexity and a constant time complexity once such round synchronization occurs. But round synchronization itself incurs an additional cost. By Dolev and Reischuk’s lower bound, any deterministic solution must have <span>\\(\\Omega (n^2)\\)</span> communication complexity. Yet the question of randomized round synchronization with an expected linear message complexity remained open. We present an algorithm that, for the first time, achieves round synchronization with expected linear message complexity and expected constant latency. Existing protocols can use our round synchronization algorithm to solve Byzantine SMR with the same asymptotic performance.\n</p>","PeriodicalId":50569,"journal":{"name":"Distributed Computing","volume":"256 1","pages":""},"PeriodicalIF":1.3000,"publicationDate":"2024-01-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Distributed Computing","FirstCategoryId":"94","ListUrlMain":"https://doi.org/10.1007/s00446-023-00459-9","RegionNum":4,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"COMPUTER SCIENCE, THEORY & METHODS","Score":null,"Total":0}
引用次数: 0
Abstract
State Machine Replication (SMR) solutions often divide time into rounds, with a designated leader driving decisions in each round. Progress is guaranteed once all correct processes synchronize to the same round, and the leader of that round is correct. Recently suggested Byzantine SMR solutions such as HotStuff, and LibraBFT achieve progress with a linear message complexity and a constant time complexity once such round synchronization occurs. But round synchronization itself incurs an additional cost. By Dolev and Reischuk’s lower bound, any deterministic solution must have \(\Omega (n^2)\) communication complexity. Yet the question of randomized round synchronization with an expected linear message complexity remained open. We present an algorithm that, for the first time, achieves round synchronization with expected linear message complexity and expected constant latency. Existing protocols can use our round synchronization algorithm to solve Byzantine SMR with the same asymptotic performance.
期刊介绍:
The international journal Distributed Computing provides a forum for original and significant contributions to the theory, design, specification and implementation of distributed systems.
Topics covered by the journal include but are not limited to:
design and analysis of distributed algorithms;
multiprocessor and multi-core architectures and algorithms;
synchronization protocols and concurrent programming;
distributed operating systems and middleware;
fault-tolerance, reliability and availability;
architectures and protocols for communication networks and peer-to-peer systems;
security in distributed computing, cryptographic protocols;
mobile, sensor, and ad hoc networks;
internet applications;
concurrency theory;
specification, semantics, verification, and testing of distributed systems.
In general, only original papers will be considered. By virtue of submitting a manuscript to the journal, the authors attest that it has not been published or submitted simultaneously for publication elsewhere. However, papers previously presented in conference proceedings may be submitted in enhanced form. If a paper has appeared previously, in any form, the authors must clearly indicate this and provide an account of the differences between the previously appeared form and the submission.