Bounded concurrrent time-stamp systems are constructible

Abstract

Concurrent time stamping is at the heart of solutions to some of the most fundamental problems in distributed computing. Based on concurrent-time-stamp-systems, elegant and simple solutions to core problems such as ƒcƒs-mutual-exclusion, construction of a multi-reader-multi-writer atomic register, probabilistic consensus,… were developed. Unfortunately, the only known implementation of a concurrent time stamp system has been theoretically unsatisfying, since it requires unbounded size time-stamps, in other words, unbounded memory. Not knowing if bounded concurrent-time-stamp-systems are at all constructible, researchers were led to constructing complicated problem-specific solutions to replace the simple unbounded ones. In this work, for the first time, a bounded implementation of a concurrent-time-stamp-system is presented. It provides a modular unbounded-to-bounded transformation of the simple unbounded solutions to problems such as above. It allows solutions to two formerly open problems, the bounded-probabilistic-consensus problem of Abrahamson [A88] and the ƒiƒo-