An architecture for modular hardware and software fault tolerance in critical real time applications

A modular approach to providing software fault tolerance has been developed by layering this capability onto the C.S. Draper Laboratory (CSDL) Fault Tolerant Processor (FTP) architecture and its Ada RTS to create the Fault Tolerant Processor with Multi-Version Software (FTP-MVS). The FTP-MVS is designed to maintain and extend the high-reliability, low-redundancy management overhead, transparency of redundancy management, and adaptability of the FTP architecture to encompass both hardware and software fault tolerance. FTPs are also used as processing sites within a highly reliable distributed system designed to meet the computational needs of advanced aerospace applications. The FTP-MVS maintains this capability and can provide software fault tolerance Within the distributed processing framework. Such a system addresses both the computational demands of an application and its reliability