Bounded Concurrent TimeStamp Systems Are Constructible

Danny Dolev Concurrent time stamping is at the heart of solu tions to some of the most fundamental problems in distributed computing. Based on concurrent time-stamp-systems, elegant and simple solu tions to core problems such as fcf,-mutual exclusion, construction of a multi-reader-multi writer atomic register. probabilistic consensus,.. were developed. Unfortunmely, the only known implementation of a concurrent time stamp sys tem has been theoretically unsatisfying since it requires unbounded size time-stamps, in other words, unbounded memory. Not knowing if bounded concurrent-time-stamp-sy stems are at all constructible, researchers were led to con structing complicated problem-specific solutions to replace the simple unbounded ones. In this work for the first time, a bounded iruplemen tation of a concurrent-time-stamp-sy stem is pre sented. It provides a modular unbounded-to-bounded transformation of the simple unbounded solutions to prob1err such as above-It al lows solutions to two formerly open problems, the bounded-probabilistic-co nsensus problem of AbrahamBon [A88] and the fifo-t-exclusion prob 1cm of IFLBB85J, and a more efficient construc tion of mrmw atomic registers.