Role-playing software architecture styles

[Abstract]: Software Architecture, from definition to maintenance and evolution, is a complex aspect of software development and, consequently, a challenging subject when it comes to teaching it, and learning it.Many research efforts have been devoted to designing teaching approaches, strategies and tools. Most of them, however, focus on the knowledge itself and the ways to convey it to students, rather than on the different learning styles of students themselves.Teaching methods which predominantly rely on verbal and written communication, are very well aligned with some learning styles. However, students with learning styles that benefit more from physical activity or first-hand experience, need to defer to cognitive processes that are less natural to them.In this work, we propose an innovative use of role-playing as teaching strategy for architecture models of reference (i.e. layered, pipe & filter, client-server, etc.). This role-playing of different software architectures, in which students play the part of specific components in the system, intends to complement other classical teaching materials, such as in-person or recorded lectures, lab assignments, or development projects.Addressing all learning styles within a classroom is key to ensure that we favour and foster the students' different learning processes, and give everyone an even playfield in which to best develop their capabilities as Software Architects.Supported by the Centro de Investigación de Galicia “CITIC”, funded by Xunta de Galicia and the European Regional Development Fund (grant ED431G 2019/01).Xunta de Galicia; ED431G 2019/0

Software architecture: styles and representational schemes

Software architecture is being widely used today to describe a very high-level design methodology of large software systems. Software architecture represents the overall structure of a system in an abstract, structured manner. A good architectural representation scheme holds the key to the effectiveness of a software architecture description and usage. In this work we look at architectural styles and architectural representation schemes. We propound the idea that the layered architectural model is a suitable candidate for a generalized architectural style and that it can cater to many different problem domains, other than the message-passing systems it has traditionally been used to model. We propose some rules by which the layered architectural style can be improved and modified in order to be able to model a wider problem domain. Then we evaluate different methods of architectural representations that have been used to model software architecture and analyze their strengths and shortcomings. We propose the use of a modified data flow diagram architecture representation scheme. This scheme is called AND-OR DFD method and is introduced and developed in this thesis. The main concept introduced here is a combination of components to form action groups to support multiple workflows and the relationships among them, without significant increase in the architectural complexity. Finally, we look at UML as a prospect for a generalized architecture description language and discuss its merits and demerits with examples

Modelling Architecture Styles

Software systems tend to increase over time in size and complexity. Their development usually spans a long period of time and often results in systems that are hard to understand, debug and maintain. Architectures are common means for organising coordination between components in order to build complex systems and make them manageable. They allow thinking on a higher plane and avoiding low-level mistakes. Grouping architectures that share common characteristics into architecture styles assists component re-use and thus, the cost-effective development of systems. Additionally, architecture styles provide means for ensuring correctness-by-construction by enforcing global properties. The main goal of this thesis is to propose and study formalisms for modelling architectures and architecture styles. For the specification of architectures, we study interaction logics, which are Boolean algebras on a set of component actions. We study a modelling methodology based on first-order interaction logic for writing architecture constraints. To validate the applicability of the approach, we developed the JavaBIP framework that integrates architectures into mainstream software development. JavaBIP receives as input architecture specifications, which it then uses to coordinate software components without requiring access to their source code. JavaBIP implements the principles of the BIP component framework. For the specification of architecture styles, we propose configuration logics, which are powerset extensions of interaction logic. Propositional configuration logic formulas are generated from formulas of interaction logic by using the operators union, intersection and complementation, as well as a coalescing operator. We provide a complete axiomatisation of the propositional configuration logic and a decision procedure for checking that an architecture satisfies given logical specifications. To allow genericity of specifications, we study higher-order extensions of the propositional configuration logic. We provide several examples illustrating the application of configuration logics to the characterisation of architecture styles. For the specification of architecture styles, we also propose architecture diagrams, which is a graphical language rooted in rigorous semantics. We provide methods to assist software developers to specify consistent architecture diagrams, generate the conforming architectures of a style and check whether an architecture model meets given style requirements. We present a full encoding of architecture diagrams into configuration logics. Finally, we report on applications of architecture diagrams to modelling architecture styles identified in realistic case studies of on-board satellite software

Architecture Diagrams: A Graphical Language for Architecture Style Specification

Architecture styles characterise families of architectures sharing common characteristics. We have recently proposed configuration logics for architecture style specification. In this paper, we study a graphical notation to enhance readability and easiness of expression. We study simple architecture diagrams and a more expressive extension, interval architecture diagrams. For each type of diagrams, we present its semantics, a set of necessary and sufficient consistency conditions and a method that allows to characterise compositionally the specified architectures. We provide several examples illustrating the application of the results. We also present a polynomial-time algorithm for checking that a given architecture conforms to the architecture style specified by a diagram.Comment: In Proceedings ICE 2016, arXiv:1608.0313

Inclusive Educational Review of Software Architectural Styles and Patterns for the Students of the College of Information and Computing Sciences of Cagayan State University

A good architectural design has a high contribution to the success of a system. In addition, this architectural design is useful for the Information Technology (IT) students as their basis of their software development of their capstone project. The utilization of inappropriate architecture can lead to disastrous consequences for IT student researchers. A detailed understanding of software architecture styles is very useful to analyze distributed and complex systems which is the trend of capstone projects. This paper explores the quality attributes of three architecture styles namely shared-nothing, broker, and representational state transfer, which are perceived as beneficial to distributed system architecture that serve as guide to student researchers. This is to provide a picture of the said three key software architecture styles which could be helpful not only for student researchers but also for the software developers by adding references to minimize the uncertainty while selecting the appropriate architectural style for their specific needs. An architectural style must be chosen correctly to obtain all its benefits in the system. In this paper, the three architectural styles are compared on the foundation of various quality attributes derived from ISO 9126-1 standard such as functionality, reliability, usability, efficiency, maintainability, and portability. The results of the study are useful to guide the student researchers in their capstone project and to reduce the number of unsuccessful attempts of software development component of their capstone project

Configuration logics: Modeling architecture styles

We study a framework for the specification of architecture styles as families of architectures involving a common set of types of components and coordination mechanisms. The framework combines two logics: 1) interaction logics for the specification of architectures as generic coordination schemes involving a configuration of interactions between typed components; and 2) configuration logics for the specification of architecture styles as sets of interaction configurations. The presented results build on previous work on architecture modeling in BIP. We show how propositional interaction logic can be extended into a corresponding configuration logic by adding new operators on sets of interaction configurations. In addition to the usual set-theoretic operators, configuration logic is equipped with a coalescing operator + to express combination of configuration sets. We provide a complete axiomatization of propositional configuration logic as well as decision procedures for checking that an architecture satisfies given logical specifications. To allow genericity of specifications, we study first-order and second-order extensions of the propositional configuration logic. First-order logic formulas involve quantification over component variables. Second-order logic formulas involve additional quantification over sets of components. We provide several examples illustrating the application of the results to the characterization of various architecture styles. We also provide an experimental evaluation using the Maude rewriting system to implement the decision procedure for the propositional flavor of the logic

Configuration Logics - Modelling Architecture Styles

We study a framework for the specification of architecture styles as families of architectures involving a common set of types of components and coordination mechanisms. The framework combines two logics: 1)~interaction logics for the specification of architectures as generic coordination schemes involving a configuration of interactions between typed components; and 2)~configuration logics for the specification of architecture styles as sets of interaction configurations. Configuration logics can be considered as a power-set extension of interaction logics. The relation between the two logics is similar to the relation between programs and their specifications. As program specifications can be expressed, \eg in temporal logics, architecture styles can be specified in configuration logics. The presented results build on previous work on architecture modelling in BIP. We show how propositional interaction logic can be extended into a corresponding configuration logic by adding new operators on sets of interaction configurations. In addition to the usual set-theoretic operators, configuration logic is equipped with a coalescing operator + to express combination of configuration sets. This operator proves to be particularly useful for the specification of architecture styles including a given class of configurations. We provide a complete axiomatization of propositional configuration logic as well as decision procedures for checking that an architecture satisfies given logical specifications. To allow genericity of specifications, we study first-order and second-order extensions of the propositional configuration logic. First-order logic formulas involve quantification over component variables. Second-order logic formulas involve additional quantification over sets of components. We provide several examples illustrating the application of the results to the characterisation of various architecture styles. We also provide an experimental evaluation using the Maude rewriting system to implement the decision procedure for the propositional flavour of the logic. We conclude with a discussion of the related work and of future directions dealing with the application of the results through the development of specific methods and tools