Information Security and Cryptography Fault Tolerant Distributed Consensus in Synchronous Networks

Traditionally, the consensus protocols are studied either in the synchronous or in the asynchronous communication setting and very often the protocols in the former category serve as the basis for the protocols in the latter category. Since its inception, fault-tolerant distributed consensus has been a widely studied topic in secure distributed computing. Thanks to the advent of blockchain technology, the topic has received renewed interest from the community. Consensus protocols are designed either in the synchronous or asynchronous communication model. The literature in each model is vast and vital enough to demand a separate monograph. Protocols and the techniques for the synchronous communication model often serve as the basis for protocols in the asynchronous model. Therefore, this work specifically focuses only on the synchronous communication model and presents all the seminal possibility and feasibility results in this model since the inception of distributed consensus protocols. Topics and features: Presents protocols both against computationally bounded and computationally unbounded adversaries Provides detailed security proofs for the seminal protocols Offers freely available companion-video lectures for some of the topics Includes pictorial illustrations for a better understanding of the underlying concepts Presents state-of-the-art efficiency improvement techniques for synchronous consensus protocols Assumes no background in cryptography or distributed computing This monograph sets out to provide a comprehensive explanation of all the essential concepts and techniques in the domain of synchronous consensus protocols and to unfold the evolution of this topic from its inception to the present. The monograph is self-contained and can be read by those familiar with discrete mathematics and algorithms. Arpita Patra is an associate professor at the Indian Institute of Science, Bangalore. Ashish Choudhury is an associate professor at the International Institute of Information Technology, Bangalore.