An Analytical Approach for Reliability Analysis of Pipeline Software Architecture

Architecture styles represent commonly occurring patterns of the structural organization of components and connectors of an application. A number of such styles have been identified and analyzed extensively for different non functional attributes including performance, maintainability, flexibility, and modifiability. The issue of reliability analysis of architecture styles, however, has been relatively less investigated. This paper presents a reliability analysis methodology for one such architecture style, namely, the pipe and filter style. Two variants of the topological organization of the pipes and filters, namely, linear topology without feedback and with feedback where the feedback loop is incorporated either to improve quality or to improve reliability are considered. The methodology derives analytical expressions for application reliability which incorporate the impact of (i) error propagation and downstream error correction, and (ii) deterministic number of iterations through the feedback loop, with filter reliabilities a function of the number of iterations. The potential of the methodology to obtain a reliability estimate and to facilitate sensitivity analysis is illustrated using an industrial case study of a Document Understanding and Analysis Application.