Planned intervention: On Wednesday April 3rd 05:30 UTC Zenodo will be unavailable for up to 2-10 minutes to perform a storage cluster upgrade.
Published November 2, 2016 | Version v1
Conference paper Open

XFT: Practical Fault Tolerance Beyond Crashes

  • 1. NUDT
  • 2. EURECOM
  • 3. IBM Research - Zurich
  • 4. Grenoble INP

Description

Despite years of intensive research, Byzantine faulttolerant (BFT) systems have not yet been adopted in practice. This is due to additional cost of BFT in terms of resources, protocol complexity and performance, compared with crash fault-tolerance (CFT). This overhead of BFT comes from the assumption of a powerful adversary that can fully control not only the Byzantine faulty machines, but at the same time also the message delivery schedule across the entire network, effectively inducing communication asynchrony and partitioning otherwise correct machines at will. To many practitioners, however, such strong attacks appear irrelevant. In this paper, we introduce cross fault tolerance or XFT, a novel approach to building reliable and secure distributed systems and apply it to the classical state-machine replication (SMR) problem. In short, an XFT SMR protocol provides the reliability guarantees of widely used asynchronous CFT SMR protocols such as Paxos and Raft, but also tolerates Byzantine faults in combination with network asynchrony, as long as a majority of replicas are correct and communicate synchronously. This allows the development of XFT systems at the price of CFT (already paid for in practice), yet with strictly stronger resilience than CFT — sometimes even stronger than BFT itself. As a showcase for XFT, we present XPaxos, the first XFT SMR protocol. Although it offers much stronger resilience than CFT SMR at no extra resource cost, the performance of XPaxos matches that of the state-of-the art CFT protocols.

Files

XFT-Practical-Fault-Tolerance-Beyond-Crashes.pdf

Files (374.9 kB)

Name Size Download all
md5:e7d2719e3c74fd8855cc2b9c02ee7030
374.9 kB Preview Download

Additional details

Funding

SUPERCLOUD – USER-CENTRIC MANAGEMENT OF SECURITY AND DEPENDABILITY IN CLOUDS OF CLOUDS 643964
European Commission