A Performance Study of Consensus Algorithms in Omission and Crash-Recovery Scenarios

We investigate the performance of the ChandraToueg and Paxos consensus algorithms, using as case study TrustedPals, a smartcard-based framework which allows to implement security policies in distributed systems. The current architecture of TrustedPals uses the Chandra-Toueg consensus algorithm adapted to the omission failure model. In this work, we propose to alternatively use the Paxos consensus algorithm, in order to extend the applicability of the framework to the crash-recovery failure model as well. We have performed simulations to compare these two consensus algorithms under different failure scenarios. Our results show that Paxos is more efficient than Chandra-Toueg if the first process which coordinates or leads a round suffers a failure, while both algorithms perform similarly when there are no failures.