Attested append-only memory: making adversaries stick to their word

Researchers have made great strides in improving the fault tolerance of both centralized and replicated systems against arbitrary (Byzantine) faults. However, there are hard limits to how much can be done with entirely untrusted components; for example, replicated state machines cannot tolerate more than a third of their replica population being Byzantine. In this paper, we investigate how minimal trusted abstractions can push through these hard limits in practical ways. We propose Attested Append-Only Memory (A2M), a trusted system facility that is small, easy to implement and easy to verify formally. A2M provides the programming abstraction of a trusted log, which leads to protocol designs immune to equivocation – the ability of a faulty host to lie in different ways to different clients or servers – which is a common source of Byzantine headaches. Using A2M, we improve upon the state of the art in Byzantine-fault tolerant replicated state machines, producing A2M-enabled protoco...

• Type: Conference
• Year: 2007
• Where: SOSP
• Authors: Byung-Gon Chun, Petros Maniatis, Scott Shenker, John Kubiatowicz
• Keywords: Minimal Trusted Abstractions, Operating System, Replicated Systems, SOSP 2007, Tolerant Replicated State