Among various systems developed for parallel and distributed computing, network of workstations (NOW) based on message passing interface (MPI) have been recognized as an efficient platform. In this paper we implement and compare two important message logging protocols, pessimistic and optimistic, for a NOW employing the MPI. The experiment reveals that the total execution time is not significantly affected by the number of failures, while the performance of optimistic protocol is more influenced by the number of failures than pessimistic protocol. Also the former is more efficient than the latter for reasonable number of failure points.