Adding Fault-Tolerance Using Pre-synthesized Components

Abstract

We present a hybrid synthesis method for automatic addition of fault-tolerance to distributed programs. In particular, we automatically specify and add pre-synthesized fault-tolerance components to programs in the cases where existing heuristics fail to add fault-tolerance. Such addition of pre-synthesized components has the advantage of reusing pre-synthesized fault-tolerance components in the synthesis of different programs, and as a result, reusing the effort put in the synthesis of one program for the synthesis of another program. Our synthesis method is sound in that the synthesized fault-tolerant program satisfies its specification in the absence of faults, and provides desired level of fault-tolerance in the presence of faults. We illustrate our synthesis method by adding pre-synthesized components with linear topology to a token ring program that tolerates the corruption of all processes. Also, we have reused the same component in the synthesis of a fault-tolerant alternating bit protocol. Elsewhere, we have applied this method for adding presynthesized components with hierarchical topology.

This work was partially sponsored by NSF CAREER CCR-0092724, DARPA Grant OSURS01-C-1901, ONR Grant N00014-01-1-0744, NSF grant EIA-0130724, and a grant from Michigan State University.