Non-functional refinement of computer based systems architecture

Abstract

Architecture based refinement is an important technique for ensuring efficiency, effectiveness and correctness in the practical design of complex computer based systems. With a few exceptions, current methods of architectural refinement focus on functional behaviour and fail to address non-functional requirements throughout the refinement process. A best practices approach to refinement would address both functional and non-functional requirements such that the refinement of an abstract into a concrete (implementation) architecture ensures that both sets of requirements are met.We propose a method that focuses on the nonfunctional requirements while still addressing the functional requirements throughout refinement. The method has a formal underpinning in abstract data types (based on term rewriting) which are used to represent the architectures throughout the refinement process and to place pre and post conditions on the refinements. In addition to this, the method uses non-functional requirement calculators to check the non-functional qualities of the architecture as refinement proceeds.Reflection on the practice of the method suggests that it may be possible to extend the architectural style idea to provide reusable refinement schema for the design of certain non-functional qualities into architectural patterns.The example considers reliability and performance in the refinement of a client server architectural pattern.The method does not aim to replace or fully automate the work of the designer. It aims to augment the design process and aid the designer in performing their tasks. It seeks to provide certain guidance for the designer that will help them make the right design decisions, and correct certain classes of errors.

Pattern-Driven Support for Designing Component-Based Architectural Models

“…The authors capture heuristics in a structured and formal manner, such that the architectural transformations can be performed for optimizing the non-functional qualities of a system. Denford et al have proposed an architectural refinement method [20] that focuses on non-functional requirements e.g., reliability, performance, while still addressing the functional requirements. While these works focus on non-functional aspects such as performance, we address architectural designs through timing constraints of embedded systems.…”

Architecture-Based Refinements for Secure Computer Systems Design

“…As some researchers have pointed out [2], [3], [5], effective refinement must be technology-and domain-specific. Also, Garlan [11] points out that refinement patterns must be explicit about what kinds of properties they are preserving in the refined design.…”

“…The overall software architecture and NFRs are closely related and should be studied together during architectural development. In the literature, much of the research focuses on how to satisfy NFRs such as reliability and performance [1], [3], [4], [5], [6], [7], instead of security. There has been some work on security architecture modelling [8], [9], but not on providing security architecture design guidance for architects.…”

Predicting Change Impact in Architecture Design with Bayesian Belief Networks

“…Other approaches such as Architecture Frame [23], KAOS [8], non-functional requirement refinement process [9] and non-functional requirement framework [4] provide various ways to decompose or refine requirements to build designs. All these structured approaches have limited support for design rationale: (a) they do not record design rationale in their models; and (b) they do not provide a way to carry out trade-off analysis amongst alternative designs.…”