Inherent fault tolerance in decentralized process-control systems

It is desirable to use redundant components to minimize the time required to accomplish a mission while at the same time ensuring that the mission will be completed in spite of failures. This characteristic is a fundamental requirement of the inherent fault tolerance approach. The authors first define inherently fault tolerant (IFT) programs and then review some theoretical aspects, namely, the correctness proof and existence conditions for IFT programs. They present two general classes of decentralized process-control systems that are amenable to IFT solutions