Colloquium Computer Science, Dr. Panagiotis Katsaros

Title: Correctness-by-Construction and Tradeoff Analysis in Software Architectures

Abstract:

Software architecture defines the structure of a system, which comprises software components, the properties of those components, and the relationships among them. Software architecture is fundamental for fulfilling trustworthiness and optimization requirements for the software system. Trustworthiness requirements capture qualitative correctness, while optimization requirements are constraints on the resources used for the implementation of the software system. Architecture designers seek trustworthiness and try to optimize resources at the same time. We present two recent approaches to address the aforementioned concerns.

A. Correctness-by-Construction aims at a design approach with measures that make it difficult to introduce defects and means to detect and remove any defects as early as possible. Formally defined architectures are used to enforce characteristic properties such as atomicity and fault tolerance. These architectures are treated as reusable design artifacts that can be composed, such that they do not interfere with each other and their properties are preserved. This perspective was first introduced in [1], where the author presents the principles of the BIP component framework for model-driven design based on formal operational semantics. We present the first results on a design flow using BIP for correct-by-construction Web Service architectures [2].

B. For optimization requirements, we present a quantitative method for discovering architecture-specific metric correlations, due to latent quality features which cannot be measured directly, but they can assist in managing potentially complex architecture tradeoffs [3]. An appropriate statistical analysis groups correlated metrics into uncorrelated components. New synthesized quality metrics are then defined that capture optimization properties in a concise and easy to interpret manner [4]. We provide experimental results based on a simulation-based evaluation of a transactional architecture that complies with the Process Coordinator pattern.

[1] J. Sifakis: Rigorous System Design. Foundations and Trends in Electronic Design Automation 6 (4): 293-362 (2013)

[2] E. Stachtiari, N. Vesyropoulos, G. Kourouleas, C.K. Georgiadis, P. Katsaros: Correct-by-Construction Web Service Architecture. SOSE 2014 (to appear)

[3] A. Mentis, P. Katsaros, L. Angelis, G. Kakarontzas: Quantification of interacting runtime qualities in software architectures: Insights from transaction processing in client-server architectures. Information & Software Technology 52(12): 1331-1345 (2010)

[4] A. Mentis, P. Katsaros, L. Angelis: Synthetic Metrics for Evaluating Runtime Quality of Software Architectures with Complex Tradeoffs. EUROMICRO-SEAA 2009: 237-242    

Colloquium coordinators are Prof.dr. M. Aiello (e-mail : M.Aiello rug.nl ) and
Prof.dr. M. Biehl (e-mail: M.Biehl rug.nl )

http://www.rug.nl/research/jbi/news/colloquia/computerscience