Abstract

This paper constructs a solvable specication and gives an algorithm for the Group Membership Problem in asynchronous systems with crash failures. Our specication requires processes to maintain a consistent history in their sequence of views. This allows to order failures and recoveries in time and simplies the programming of many high level applications. Previous work proved that the Group Membership Problem cannot be solved in asynchronous systems with crash failures. We identify the main assumptions required for this proof and show how to circumvent this impossibility result building a weaker, yet non trivial specication. We show that our solution is an improvement upon previous attempts to solve this problem using a weaker specication. We also relate our solution to other methods used to circumvent the impossibility result and give a classication of progress properties that can be achieved under dierent models. Keywords: distributed agreement algorithms, group memb...

Citations