An approach of change impact analysis in web systems

University of Technology, Sydney. Faculty of Engineering and Information Technology.There are currently a high number of Web systems being developed; therefore, any consideration towards improving Web systems development practices will be worthy of research effort. Web systems are intricately interwoven into business processes so as to be supported by those systems. In other words, there are a multitude of fined-grained interconnections between business processes and the supporting architecture. Keeping in view the fine-grained interconnections, any change made in business processes can typically lead to more pervasive changes at the architecture (as compared to traditional software systems). Consequently, there is a much more fine-grained evolution at the architecture level in order to address the intricately interwoven characteristic. Partly as a consequence of the intricately interwoven characteristic, the connection between business processes and the architecture solution are also much tighter than for traditional software systems. Given this tight-connection, any change in business processes often leads to fundamental changes at the supporting architecture. Additionally, while addressing changes in business processes, a single change in architecture may have substantial impacts on other parts of the architecture and result in the ripple effects of the change being made to architecture. The intricately interwoven characteristics, underpinning fine-grained evolution and the tight connection between business processes and the architecture design tend to differentiate Web systems from traditional software systems. To support the evolution and tight connection between business processes and architecture design, it would be beneficial to identify what needs to be modified in architecture to address business processes changes. Failure in attempts to identify change impacts on the architecture resulting from business processes changes leads to the problem where implementation (detailed design) begins before the impacts (on architecture) are adequately identified. As a consequence, many of the change impacts caused by business processes changes may go undetected or are identified very late and often lead to unnecessary re-work during the later stages of system development. We will refer to the identification of change impact on architecture before detailed design actually begins as “early identification of change impacts” in Web systems. As presented in this thesis, the investigation from current state of the practices form a set of high level features/needs that a change impact analysis approach should support for Web systems. Keeping in view both the industrial perspectives and the issue where implementation (detailed design) actually begins before the change impacts (on architecture) are adequately identified, we proposed a systematic, structured and rigorous approach termed as the process model of CIA (PMCIA). We have captured various elements and necessary components derived both from the state of the art and state of the practice for the development of the process model of CIA. We have validated it with an industrial case study. The case study findings indicate that with the use of process model of CIA, practitioners indeed get support for early identification of change impacts in Web systems project and acquire an increased understanding of employing design information during change impact analysis

Sustainability evaluation of software architectures

Long-living software systems are sustainable if they can be cost-efficiently maintained and evolved over their entire life-cycle. The quality of software architectures determines sus-tainability to a large extent. Scenario-based software archi-tecture evaluation methods can support sustainability anal-ysis, but they are still reluctantly used in practice. They are also not integrated with architecture-level metrics when evaluating implemented systems, which limits their capabil-ities. Existing literature reviews for architecture evaluation focus on scenario-based methods, but do not provide a criti-cal reflection of the applicability of such methods for sustain-ability evaluation. Our goal is to measure the sustainabil-ity of a software architecture both during early design us-ing scenarios and during evolution using scenarios and met-rics, which is highly relevant in practice. We thus provide a systematic literature review assessing scenario-based meth-ods for sustainability support and categorize more than 40 architecture-level metrics according to several design prin-ciples. Our review identifies a need for further empirical research, for the integration of existing methods, and for the more efficient use of formal architectural models. 1

Focus Issue on Legacy Information Systems and Business Process Change: Migrating Large-Scale Legacy Systems to Component-Based and Object Technology: The Evolution of a Pattern Language

The process of developing large-scale business critical software systems must boost the productivity both of the users and the developers of software, while at the same time responding flexibly to changing business requirements in the face of sharpening competition. Historically, these two forces were viewed as mutually hostile. Component-based software development using object technology promises a way of mediating the apparent contradiction. This paper presents a successful new approach which focuses primarily on the architecture of the software system to migrate an existing system to a new form. Best practice is captured by software patterns that address not only the design, but also the process and organizational issues. The approach was developed through four completed, successful live projects in different business and technical areas. It resulted in a still-evolving pattern language called ADAPTOR (Architecture-Driven and Pattern-based Techniques for Object Re-engineering). This article outlines the approach that underlies ADAPTOR. It challenges popular notions of legacy systems by emphasizing business requirements. Architectural approaches to migration are then contrasted with traditional reverse engineering approaches, including the weakness of reverse engineering in the face of paradigm shifts. The evolution of the ADAPTOR pattern language is outlined with a brief history of the projects from which the patterns were abstracted

L'open source come modello di sviluppo dell'abitare contemporaneo

In the last years Open source has emerged due to its success in the production of reliable and robust software. Its paradigm about software production, collectively-created programs in a process where users are also developers (to different degrees), has underlined the effectiveness of open and community-based systems compared to proprietary and closed standards, highlighting the cheapness and the flexibility in the adaptation to different situations. This paper aims to investigate the introduction of the open source development methodology in the field of architecture (mainly in the field of living) through the collection and analysis of some recent projects and initiatives, in order to give a first possible definition of open source architecture and trying to identify some of the main directions of action for the design, creation and management of platforms that host trans-scalar community of users focused on transforming the built environment in a sustainable, adaptable and low-cost way. Each case study (including Architecture for Humanity, Wikihouse, Shanghai Air Tree and others) tried to develop, in different forms and methods, some architectural tools based on communities of users that can design and build architectural objects able to respond and adapt to needs of local communities that want to increase spontaneously the quality of public spaces and dwelling. Based primarily on the use of digital information and its ease of transmission, reading and manipulation, and by exploiting also the spread of digital fabrication, the proliferation of electronic devices and accessible design software (eg. Sketchup) and the use of licenses suitable for sharing, the examined cases deepen the theme of open source applied to architecture underlining a complex and dynamic landscape in continuous evolution. The analytical work has led to the categorization and organization of case studies and their subsequent comparison, in an attempt to provide a snapshot view of the phenomenon of open source architecture, in order to assess the possible impacts and consequences for the practice of architecture, the sustainable transformation of the built environment and the ability to deal nimbly new phenomena that affect and change contemporary livin

Continuous Experimentation for Automotive Software on the Example of a Heavy Commercial Vehicle in Daily Operation

As the automotive industry focuses its attention more and more towards the software functionality of vehicles, techniques to deliver new software value at a fast pace are needed. Continuous Experimentation, a practice coming from the web-based systems world, is one of such techniques. It enables researchers and developers to use real-world data to verify their hypothesis and steer the software evolution based on performances and user preferences, reducing the reliance on simulations and guesswork. Several challenges prevent the verbatim adoption of this practice on automotive cyber-physical systems, e.g., safety concerns and limitations from computational resources; nonetheless, the automotive field is starting to take interest in this technique. This work aims at demonstrating and evaluating a prototypical Continuous Experimentation infrastructure, implemented on a distributed computational system housed in a commercial truck tractor that is used in daily operations by a logistic company on public roads. The system comprises computing units and sensors, and software deployment and data retrieval are only possible remotely via a mobile data connection due to the commercial interests of the logistics company. This study shows that the proposed experimentation process resulted in the development team being able to base software development choices on the real-world data collected during the experimental procedure. Additionally, a set of previously identified design criteria to enable Continuous Experimentation on automotive systems was discussed and their validity confirmed in the light of the presented work.Comment: Paper accepted to the 14th European Conference on Software Architecture (ECSA 2020). 16 pages, 5 figure

Assessing architectural evolution: A case study

This is the post-print version of the Article. The official published can be accessed from the link below - Copyright @ 2011 SpringerThis paper proposes to use a historical perspective on generic laws, principles, and guidelines, like Lehman’s software evolution laws and Martin’s design principles, in order to achieve a multi-faceted process and structural assessment of a system’s architectural evolution. We present a simple structural model with associated historical metrics and visualizations that could form part of an architect’s dashboard. We perform such an assessment for the Eclipse SDK, as a case study of a large, complex, and long-lived system for which sustained effective architectural evolution is paramount. The twofold aim of checking generic principles on a well-know system is, on the one hand, to see whether there are certain lessons that could be learned for best practice of architectural evolution, and on the other hand to get more insights about the applicability of such principles. We find that while the Eclipse SDK does follow several of the laws and principles, there are some deviations, and we discuss areas of architectural improvement and limitations of the assessment approach

Evaluating Software Architectures: Development Stability and Evolution

We survey seminal work on software architecture evaluationmethods. We then look at an emerging class of methodsthat explicates evaluating software architectures forstability and evolution. We define architectural stabilityand formulate the problem of evaluating software architecturesfor stability and evolution. We draw the attention onthe use of Architectures Description Languages (ADLs) forsupporting the evaluation of software architectures in generaland for architectural stability in specific

Software, architecture, and participatory design

Much work in software architecture has been inspired by work in physical architecture, in particular Alexander's work on `design patterns'. By contrast, Alexander's work is little-used in town planning and architecture. In this paper, we examine some of the reasons that this is so, describe some parallels and differences between the fields of physical and software architecture, and identify areas in which future collaboration may be fruitful. The notion of `participatory design' is important in software engineering and in urban regeneration, but the participatory mechanisms in each field are quite different