Active Replication in Delta-4

M. Chérèque, D. Powell, P. Reynier, J.-L. Richier and J. Voiron



Delta-4 is an open dependable distributed computing systems architecture, in which fault-tolerance is achieved by means of replication of run-time software components on host computers interconnected by a local area network. Several replication techniques have been designed and implemented; this paper concentrates on the coordination of active replicas executing either in a fail-silent host computer environment, or in a fail-uncontrolled one. This coordination is carried out by a specific protocol, the Inter Replica protocol.