Component Replication Based on Failover Units

Although component middleware is increasingly used to develop distributed, real-time and embedded (DRE) systems, it poses new fault tolerance challenges, such as the need for efficient synchronization of internal component state, failure correlation across groups of components, and configuration of fault-tolerance properties at the component granularity level. This paper makes two contributions to R&D on component-based fault-tolerance. First, we present the structure and functionality of our component replication based on failover units (CORFU) middleware, which provides fail-stop behavior and fault correlation across groups of components in DRE systems. Second, we empirically evaluate CORFU and compare/contrast it with existing object-oriented fault-tolerance methods. Our results show that component middleware (1) has acceptable fault-tolerance performance for DRE systems and (2) eases the burden of application development by providing middleware support for fault-tolerance at the component level.