A TIME-FREE ASSUMPTION TO IMPLEMENT EVENTUAL LEADERSHIP
Abstract
Leader-based protocols rest on a primitive able to provide the processes with the same unique leader. Such protocols are very common in distributed computing to solve synchronization or coordination problems. Unfortunately, providing such a primitive is far from being trivial in asynchronous distributed systems prone to process crashes. (It is even impossible in fault-prone purely asynchronous systems.) To circumvent this difficulty, several protocols have been proposed that build a leader facility on top of an asynchronous distributed system enriched with synchrony assumptions. This paper introduces a novel approach to implement an eventual leader protocol, namely a time-free behavioral assumption on the flow of messages that are exchanged. It presents a very simple leader protocol based on this assumption. It then presents a second leader protocol combining this timeless assumption with eventually timely channels. As it considers several assumptions, the resulting hybrid protocol has the noteworthy feature to provide an increased overall assumption coverage. A probabilistic analysis shows that the time-free assumption is practically always satisfied.
References
M. K. Aguilera , On Implementing Omega with Weak Reliability and Synchrony Assumptions, Proc. 22th ACM Symposium on Principles of Distributed Computing (PODC'03) (ACM Press, 2003) pp. 306–314. Google ScholarM. K. Aguilera , Communication-Efficient Leader Election and Consensus with Limited Link Synchrony, Proc. 23th ACM Symposium on Principles of Distributed Computing (PODC'04) (ACM Press, 2004) pp. 328–337. Google Scholar- Journal of Computer and System Sciences 68, 123 (2004). Crossref, ISI, Google Scholar
- Journal of the ACM 43(2), 225 (1996). Crossref, ISI, Google Scholar
- Journal of the ACM 43(4), 685 (1996). Crossref, ISI, Google Scholar
- Journal of the ACM 35(2), 288 (1988). Crossref, ISI, Google Scholar
C. Fetzer , M. Raynal and F. Tronel , An Adaptive Failure Detection Protocol, Proc. 8th IEEE Pacific Rim Int'l Symposium on Dependable Computing (PRDC'01) (IEEE Computer Society Press, 2001) pp. 146–153. Google Scholar- Journal of the ACM 32(2), 374 (1985). Crossref, ISI, Google Scholar
R. Guerraoui , Indulgent Algorithms, Proc. 19th ACM Symposium on Principles of Distributed Computing, (PODC'00) (ACM Press, 2000) pp. 289–298. Google Scholar- IEEE Transactions on computers 53(4), 453 (2004). Crossref, ISI, Google Scholar
N. Hayashibara , The ϕ Accrual Failure Detector, Proc. 23th IEEE Symposium on Reliable Distributed Systems (SRDS'04) (IEEE Computer Society Press, 2004) pp. 66–78. Google Scholar- ACM Transactions on Computer Systems 16(2), 133 (1998). Crossref, ISI, Google Scholar
M. Larrea , A. Fernandez and S. Arevalo , Optimal Implementation of the Weakest Failure Detector for Solving Consensus, Proc. 19th Symposium on Reliable Distributed Systems (SRDS'00) (IEEE Computer Society Press, 2000) pp. 52–60. Google Scholar- Future Generation Computer Systems 18(6), 757 (2002). Crossref, ISI, Google Scholar
A. Mostefaoui , E. Mourgaya and M. Raynal , Asynchronous Implementation of Failure Detectors, Proc. Int. IEEE Conference on Dependable Systems and Networks (DSN'03) (IEEE Computer Society Press, 2003) pp. 351–360. Google ScholarA. Mostefaoui , D. Powell and M. Raynal , A Hybrid Approach for Building Eventually Accurate Failure Detectors, Proc. 10th IEEE Int. Pacific Rim Dependable Computing Symposium (PRDC'04) (IEEE Computer Society Press) pp. 57–65. Google ScholarA. Mostefaoui and M. Raynal , Low-Cost Consensus-Based Atomic Broadcast, 7th IEEE Pacific Rim Int. Symposium on Dependable Computing (PRDC'2000) (IEEE Computer Society Press, 2000) pp. 45–52. Google Scholar- Parallel Processing Letters 11(1), 95 (2001). Link, Google Scholar
A. Mostefaoui , M. Raynal and C. Travers , Crash-Resilient Time-free Eventual Leader-ship, Proc. 23th IEEE Symposium on Reliable Distributed Systems (SRDS'04) (IEEE Computer Society Press, 2004) pp. 208–217. Google ScholarD. Powell , Failure Mode Assumptions and Assumption Coverage, Proc. of the 22nd Int. Symp. on Fault-Tolerant Computing (FTCS-22) (1992) pp. 386–395. Google Scholar


