A software architecture for translucent replication

Abstract

This paper outlines the expected research contribution of my Ph.D. thesis in the area of middleware for dependability. Dependability is a long-standing desirable property for today's network-based service applications but requirements of dependable systems are often conflicting in many ways, especially when dealing with performance related aspects. I describe a novel approach called translucent replication to address the conflicts between dependability and performance. The proposed solution is a software architecture with two key aspects: (i) enhanced intra-layer and cross-layer interaction, for flexibility and extensibility of the application/middleware infrastructure; and (ii) a semantic knowledge repository that enables smart middleware behavior, providing adaptation by matching application dependability needs, specific to data being replicated, and the system working conditions. Exploiting translucent replication, application designers can explore operating regions (instead of single points) in the dependability design-space, and dynamically investigate sets of solutions for the conflicts between dependability and performance. After presenting the general model, a realization of translucent replication within the context of a JMS solution is evaluated, to demonstrate the validity of this approach.