Implementation of design fault tolerance based on a standardization project for operating systems

Abstract

Many designers of high-reliability systems are now turning to design diversity as a technique of design fault tolerance. In this approach, parallel components in a system are not identical, but have different internal design and are developed by multiple teams working independently to a single external specification. Treating a standardization project involving multiple implementers as equivalent to design diversity, the authors have been investigating a multilevel design diversity architecture in which the design diversity approach is applied to application programs, the operating system, and hardware in accordance with the TRON standardization guidelines. This paper reports a backup error recovery mechanism for the operating system, focusing on a reconfiguration mechanism for modules that differ in their internal design. The mechanism was developed for modules developed independently by three suppliers under the ITRON2 operating system specification. The provision for reconfiguration required the rewriting of only 0.8% of the source code for the modules. © 1997 Scripta Technica, Inc. Syst Comp Jpn. 28 (1): 113–120, 1997