Depot: from Byzantine Fault Tolerance to Eventual Consistency in a Single System

Speaker(s) : Allen Clement (MPI-SWS, Saarbrücken, Allemagne)
Cloud services such as S3, EC2 and Azure are increasingly used by companies large and small as replacements for local compute and storage infrastructure. While this can offer significant savings, it is not without risk as data stored with a third party could be lost or corrupted thanks to misconfigurations, operator error, or simply going out of business. Byzantine fault tolerant replication promises to solve these problems, but the 3f+1 replication requirements are both prohibitive and untenable.
In this talk I will present Depot, a system for replicating data across multiple potentially Byzantine third party service providers with substantially fewer than 3f+1 replicas. The key to achieving this reduction in replication requirements is recognizing a fundamental symmetry between Byzantine behavior and concurrent executions; enabling us to leverage eventual consistency to tolerate Byzantine faults.

Marc.Shapiro (at)