Byzantine Fault Tolerance for Nondeterministic Applications

All practical applications contain some degree of nondeterminism. When such applications are replicated to achieve Byzantine fault tolerance (BFT), their nondeterministic operations must be controlled to ensure replica consistency. To the best of our knowledge, only the most simplistic types of replica nondeterminism have been dealt with. Furthermore, there lacks a systematic approach to handling common types of nondeterminism. In this paper, we propose a classification of common types of replica nondeterminism with respect to the requirement of achieving Byzantine fault tolerance, and describe the design and implementation of the core mechanisms necessary to handle such nondeterminism within a Byzantine fault tolerance framework.Comment: To appear in the proceedings of the 3rd IEEE International Symposium on Dependable, Autonomic and Secure Computing, 200

Practical Byzantine Fault Tolerance, un algoritme de consens capaç de competir amb Proof-of-Work

Research of the Practical Byzantine Fault Tolerance consensus algorithm (PBFT) and Federated Byzantine Agreement (FBA) against the most used technologies in blockchain, Proof-of-Work (PoW) and Proof-of-Stake (PoS) It also includes the analysis of the Zookeper Atomic Broadcast algorithm (Zab)Investigación del algortimo de consenso Practical Byzantine Fault Tolerance (PBFT) y de su derivada Federated Byzantine Agreement (FBA) en contra de las tecnologias más utilizadas en el ámbito de las blockchain, Proof-of-Work (PoW) y Proof-of-Stake (PoS) También incluye el análisis del algoritmo Zookeper Atomic Broadcast (Zab)Investigació de l'algortime de consens Practical Byzantine Fault Tolerance (PBFT) i de la seva derivada Federated Byzantine Agreement (FBA) enfront de les tecnologies més utilitzades en làmbit de les blockchain, Proof-of-Work (PoW) i Proof-of-Stake (PoS) També inclou l'analisis de l'algortime Zookeper Atomic Broadcast (Zab

Byzantine Fault Tolerance for Nondeterministic Applications

The growing reliance on online services accessible on the Internet demands highly reliable system that would not be interrupted when encountering faults. A number of Byzantine fault tolerance (BFT) algorithms have been developed to mask the most complicated type of faults - Byzantine faults such as software bugs,operator mistakes, and malicious attacks, which are usually the major cause of service interruptions. However, it is often difficult to apply these algorithms to practical applications because such applications often exhibit sophisticated non-deterministic behaviors that the existing BFT algorithms could not cope with. In this thesis, we propose a classification of common types of replica nondeterminism with respect to the requirement of achieving Byzantine fault tolerance, and describe the design and implementation of the core mechanisms necessary to handle such replica nondeterminism within a Byzantine fault tolerance framework. In addition, we evaluated the performance of our BFT library, referred to as ND-BFT using both a micro-benchmark application and a more realistic online porker game application. The performance results show that the replicated online poker game performs approximately 13 slower than its nonreplicated counterpart in the presence of small number of player

Byzantine Fault Tolerance for Nondeterministic Applications

The growing reliance on online services accessible on the Internet demands highly reliable system that would not be interrupted when encountering faults. A number of Byzantine fault tolerance (BFT) algorithms have been developed to mask the most complicated type of faults - Byzantine faults such as software bugs,operator mistakes, and malicious attacks, which are usually the major cause of service interruptions. However, it is often difficult to apply these algorithms to practical applications because such applications often exhibit sophisticated non-deterministic behaviors that the existing BFT algorithms could not cope with. In this thesis, we propose a classification of common types of replica nondeterminism with respect to the requirement of achieving Byzantine fault tolerance, and describe the design and implementation of the core mechanisms necessary to handle such replica nondeterminism within a Byzantine fault tolerance framework. In addition, we evaluated the performance of our BFT library, referred to as ND-BFT using both a micro-benchmark application and a more realistic online porker game application. The performance results show that the replicated online poker game performs approximately 13 slower than its nonreplicated counterpart in the presence of small number of player

Byzantine Fault Tolerance for Nondeterministic Applications

The growing reliance on online services accessible on the Internet demands highly reliable system that would not be interrupted when encountering faults. A number of Byzantine fault tolerance (BFT) algorithms have been developed to mask the most complicated type of faults - Byzantine faults such as software bugs,operator mistakes, and malicious attacks, which are usually the major cause of service interruptions. However, it is often difficult to apply these algorithms to practical applications because such applications often exhibit sophisticated non-deterministic behaviors that the existing BFT algorithms could not cope with. In this thesis, we propose a classification of common types of replica nondeterminism with respect to the requirement of achieving Byzantine fault tolerance, and describe the design and implementation of the core mechanisms necessary to handle such replica nondeterminism within a Byzantine fault tolerance framework. In addition, we evaluated the performance of our BFT library, referred to as ND-BFT using both a micro-benchmark application and a more realistic online porker game application. The performance results show that the replicated online poker game performs approximately 13 slower than its nonreplicated counterpart in the presence of small number of player

Evaluating Byzantine-Based Blockchain Consensus Algorithms for Sarawak’s Digitalized Pepper Value Chain

A chosen network structure of Practical Byzantine Fault Tolerance (PBFT), a Byzantine-based consensus algorithm, is proposed to minimize some of the identified pain points faced by the pepper stakeholders. Byzantine-based consensus algorithms are used to achieve the same agreement on a single data value, including transactions and block state, and to maintain system continuity even when several nodes have failed to respond or transmit inconsistent messages in the blockchain network

Extending Byzantine Fault Tolerance to Replicated Clients

Byzantine agreement protocols for replicated deterministic state machines guarantee that externally requested operations continue to execute correctly even if a bounded number of replicas fail in arbitrary ways. The state machines are passive, with clients responsible for any active ongoing application behavior. However, the clients are unreplicated and outside the fault-tolerance boundary. Consequently, agreement protocols for replicated state machines do not guarantee continued correct execution of long-running client applications. Building on the Castro and Liskov Byzantine Fault Tolerance protocol for unreplicated clients (CLBFT), we present a practical algorithm for Byzantine fault-tolerant execution of long-running distributed applications in which replicated deterministic clients invoke operations on replicated deterministic servers. The algorithm scales well to large replica groups, with roughly double the latency and message count when compared to CLBFT, which supports only unreplicated clients. The algorithm supports both synchronous and asynchronous clients, provides fault isolation between client and server groups with respect to both correctness and performance, and uses a novel architecture that accommodates externally requested software upgrades for long-running evolvable client applications

ByzID: Byzantine Fault Tolerance from Intrusion Detection

Building robust network services that can withstand a wide range of failure types is a fundamental problem in distributed systems. The most general approach, called Byzantine fault tolerance, can mask arbitrary failures. Yet it is often considered too costly to deploy in practice, and many solutions are not resilient to performance attacks. To address this concern we leverage two key technologies already widely deployed in cloud computing infrastructures: replicated state machines and intrusiondetection systems.First, we have designed a general framework for constructing Byzantine failure detectors based on an intrusion detection system. Based on such a failure detector, we have designed and built a practical Byzantine fault-tolerant protocol, which has costs comparable to crash-resilient protocols like Paxos. More importantly, our protocol is particularly robust against several key attacks such as flooding attacks, timing attacks, and fairness attacks, that are typically not handled well by Byzantine fault masking procedures