Summary: A Recipe for Atomic Semantics for Byzantine Quorum Systems
Evelyn Pierce \Lambda Lorenzo Alvisi y
April 18, 2000
We present a formal proof that the problem of atomic semantics [Lam86] for Byzantine quo
rum systems with trustworthy clients can be reduced to that of regular semantics. Specifically,
any regular protocol for such systems can be combined with a writeback mechanism to produce
an atomic protocol. We then give a pseudoregular protocol for general masking quorum systems
[MR98a] and show that it can be used in this way to build a pseudoatomic protocol.
keywords: atomic variable semantics, byzantine fault tolerance, quorum systems,
largescale data services, calculational proofs
\Lambda Department of Computer Sciences, University of Texas, Austin, Texas; email@example.com.
y Department of Computer Sciences, University of Texas, Austin, Texas; firstname.lastname@example.org.
Byzantine quorum systems [MR98a] are a promising approach to the problem of efficiently im
plementing Byzantine faulttolerant data services. There are several variations on this approach
[Baz97, MRWr97, MRW97, MR98a] but the basic concept is the same: data are maintained si
multaneously at multiple sites, and each read or write operation is processed at a subset (called a