A Hierarchical Program Structure for Concurrent Fault Tolerant Software

A new approach to software fault tolerance in concurrent programs modeled as reactive systems is proposed. It is based on a hierarchical structure and on the combined use of different fault tolerant schemes (e.g. transaction to protect data and conversation like scheme to protect processes). Among the merits of this new approach there is the possibility of an effective use of different programming languages to implement diverse software versions also in concurrent programs