A pattern language for the evolution of component-based software architectures

In order to solve the problem of the complexity of software system and the efficiency of large-scale collaboration, software architecture design methods have gradually developed. In the process of software architecture evolution, users and concurrency are increasing day by day, and software technology is constantly evolving and improving accordingly. Although there are many researches and technical discussions on software architecture methodology, there are few papers that fully discuss the development of technology in terms of the evolution of the architecture. This paper takes the evolution of software architecture as the research object, discusses problems, solutions and related technologies involved in the evolution of software architecture, and comprehensively explains how the system gradually evolves from a single architecture to a complex high-concurrency architecture. KeywordsArchitecture designArchitecture evolutionHigh concurrency

Virtually all software systems of significant size and longevity eventually undergo changes to their basic architectural structure. Such changes may be prompted by new feature requests, new quality attribute requirements, changing technology, or other reasons. Whatever the cause, software architecture evolution is commonplace in real-world software projects. However, research in this area has suffered from problems of validation; previous work has tended to make heavy use of toy examples and hypothetical scenarios and has not been well supported by real-world examples. To help address this problem, this paper presents a case study of an ongoing effort at the Jet Propulsion Laboratory to rearchitect the Advanced Multimission Operations System used to operate NASA's deep-space and astrophysics missions. Based on examination of project documents and interviews with project personnel, I describe the goals and approach of this evolution effort, then demonstrate how approaches and formal methods from previous research in architecture evolution may be applied to this evolution while using languages and tools already in place at the Jet Propulsion Laboratory.

Welcome you to the Fifth Edition of the track Software Architecture: Theory, Technology, and Applications (SA-TTA 2017) as part of the 32th ACM/SIGAPP Symposium on Applied Computing (SAC).

The software industry increasingly needs to consider architecture evolution in the context of industrial ecosystem platforms. These environments feature a large number third-party offerings with a high variety and complexity of design and technology options. The software architects working on platform migration and in-platform evolution scenarios in such environments require support to find and utilize optimal offerings, ensure design compatibility with various technical and non-technical constraints, and optimize architectures. Based on a multi-case study of three industrial cases, we have derived an architecture knowledge model that provides a basis for supporting software architects in platform migration and in-platform evolution scenarios.

Modern computing and network environments demand ahigh degree of adaptability from applications. At run time, an application may have to face many changes: in configuration, in protocols used, in terms of the available resources, etc. Many such changes can only be adequately addressed through dynamic evolution of the software architecture of the application. In this paper, we propose a novel approach to dynamically evolve a software architecture based on run-time aspect oriented programming. In our framework, a system designer/administrator can control the architecture of an application by dynamically inserting and removing code extensions. It is even possible to replace a significant part of the underlying middleware infrastructure without stopping the application. The novelty of this work is that it allows for a much more flexible development strategy as it delegates issues like middleware choice and adherence to an architectural specification to a framework enhanced by dynamic code extensions.

Change is an intrinsic property of software.A software system, during its lifetime, may require several updates, improvements, or new features.If these change requirements are not addressed, the risk of becoming a useless system increases.In fact, this is a challenging issue of safety-and mission-critical software systems, which cannot be stopped to perform maintenance or evolution operations due to their continuous operation.To reduce the aging of these critical systems, they must be provided with mechanisms enabling their dynamic evolution, i.e. the support of changes on their structure and behaviour while they remain in operation.This thesis is concerned with the design of a framework to build architecturebased, dynamically evolvable, software systems.The fact that this framework is a software architecture based approach provides the following advantages: (i) it offers a high-level of abstraction for describing dynamic changes; (ii) it allows varying the level of system description; and (iii) it advantages from the existing support for system modelling, code-generation, and formal analysis provided by architecture description languages.The framework presented in this thesis, called Dynamic PRISMA, is characterized by the combination of two levels of dynamism: Dynamic Reconfiguration, which addresses changes at the configuration level (i.e. the architectural configuration), and Dynamic Type Evolution, which addresses changes at the type-level (i.e. the specification of architectural types and instances).This combination is one of the major contributions of this thesis: thus a system is not only able to reconfigure at runtime the building blocks it is composed of (i.e.architectural types), but also to redefine these building blocks (or introduce new ones) at runtime.Another contribution of the thesis is the identification of the concerns related to dynamic evolution and their integration in the framework through aspects.This improves the separation of concerns and allows us to change reconfiguration specifications, evolution mechanisms, or the business logic independently of each other.A third contribution of this thesis is how this dynamism is supported: reconfiguration through autonomic capabilities, which provides proactivity according to either internal or external stimuli; and type evolution through asynchronous reflection, which enables the modification of a type specification and the transformation of their instances at different rates (i.e. when they are ready for evolution).Specifically, the asynchronous evolution vi semantics is precisely described by means of graph transformations.This formalism has been chosen because it naturally models both the system architecture and its asynchronous evolution.The work presented in this thesis is illustrated through a case study from the robotics domain; an area which could potentially benefit from the results of this thesis.

Managing evolution of complex software architecture is a continuous challenge in industry. Systems such as mobile handsets undergo a continuous increase in complexity, while the fast market evolution imposes quick integration of new features. Being able to easily manage software architecture evolution is the basis for shorter time-to-market and faster product release. The term “viewpoint” has become familiar with the publication of the IEEE standard 1471–2000 on recommended practices for architectural modelling. Based on the classical 4+1 view model, we have elaborated our own set of viewpoints in order to support our domain-specific architectural modelling needs. We hereby justify the introduction of the architectonic viewpoint, which models the evolutionary aspects of software architecture. The term, as well as the rationale behind it, is inspired from architecture as in buildings. We describe the viewpoint and the way it links to the others we use. Additionally, we briefly elaborate on the other viewpoints that we use for architectural modelling of mobile telephone software architecture. We provide basis for discussion and further research into the matter.

The work of architect Christopher Alexander in articulating the field of pattern languages for architecture has been extended to several other fields, notably object oriented software development, project management and technology management. Alexander calls for the identification of patterns in areas of creativity (e.g. architecture, programming) and human activity (e.g. project management) which when taken together form a comprehensive and interrelated set of entities comprising a language that defines best practices in that area. Alexander has a well defined process to identify patterns and criteria for selecting and creating patterns beneficial for action by the practitioner. Most often the discovery of patterns and development of a language for a field of practice is done by a community of practitioners. This paper presents the application of Alexander's pattern language approach to innovation management practice. Specifically it proposes the development of a community of practice composed of technology managers, both practitioners and academics, to discover and publish patterns and form a pattern language for the practice of innovation management. Examples of patterns in innovation management are presented as a starting point in the discussion.

With increasing demands and changing environment on software systems, a major challenge for those systems is to evolve themselves to adapt to these variations, especially during their running, where dynamic evolution of software architectures has been a key issue of software dynamic evolution research. Most current research in this direction focuses on describing dynamic evolution process of software architectures, and lack consistency analysis of dynamic evolution of software architectures. In this paper, we propose to represent software architectures with constraint hypergraphs, model dynamic evolution of software architectures with constraint hypergraph grammars, and discuss the consistency condition and corresponding consistency decision method of dynamic evolution of software architectures. Our approach provides a formal theoretical basis and a user-friendly graphical representation for consistency analysis of dynamic evolution of software architectures.

This paper aims to focus on database configuration of process control systems during project engineering phase and the impact of initial configuration on their performances and lifetime. We will start by highlighting operation principle of such systems, taking as example DCS systems (Distributed Control Systems) where we discussed their hardware and software architecture evolution and then identify the most common problems encountered on these systems. Through a case study, we will focus on the optimization of database configuration and see how could bad configuration practices reduce the control system performances and then may affect industrial process operation. The case study discussed is about a DCS system installed to control oilfield processing facilities where hardware and software description on this control system is given. We will emphasize on system deficiencies which the most important of them is the problem of database memory saturation which causes significant system performances and lifetime decreases.KeywordsProcess control system (PCS)Distributed control system (DCS)Database configurationMemory saturationSystem performance and lifetime

Migration from monolithic software systems to modern microservice architecture is a critical process for enhancing software systems' scalability, maintainability, and performance. This study conducted a systematic literature review to explore the various methodologies, techniques, and algorithms used in the migration of monolithic systems to modern microservice architectures. Furthermore, this study underscored the role of artificial intelligence in enhancing the efficiency and effectiveness of the migration process by examining recent literature to identify significant patterns, challenges, and optimal solutions. In addition, it emphasizes the importance of migrating monolithic systems into microservices by synthesizing various research studies that enable greater flexibility, fault tolerance, and independent scalability. The findings offer valuable insights for both researchers and practitioners in the software industry. In addition, it provides practical guidance on implementing AI-driven methodologies in software architecture evolution. Finally, we highlight future research directions in providing an automation technique for the software architecture migration.

Cloud computing made a big impact on software architecture evolution. The demand to serve multiple tenants, to include continuous delivery practice into the development process as well as increased system load influenced the style of cloud based software architecture. Microservice architecture is preferred architecture despite its complexity when scalability is an essential attribute of quality of service. Microservices should be managed, i.e., hardware resources should be adjusted based on application load, as well as resiliency should be ensured. Popular IaaS and PaaS providers such as Amazon, Azure or OpenStack ensure auto-scaling and elasticity at the infrastructure level. This approach has the following limitations: (1) Scaling and resiliency is a part of the infrastructure and not emerging from application nature; (2) The software is locked in with a specific vendor; (3) It might be difficult to run and ensure smooth scalability by running software on different vendors at the same time. We are creating auto-scaling module for microservice-based applications. Collecting metrics both at infrastructure and application levels is one important task for auto-scaling. We’ve chosen to investigate ELK stack and build appropriate architecture around it.

This paper deals with the change in architecture and urban culture, before the reference to Western models had yet become explicit and dominant. One noteworthy factor for urban history in the second half of the seventeenth century was the preference of many sultans for Edirne. The people of Istanbul noted and resented the frequent absence of the sultans from the city. Commercial growth, the closer link of monumental architecture with the active parts of the city, and the role of court ladies as patrons, were fundamental factors of Istanbul's physical and architectural evolution in that period. The commercial areas of the city expanded in apparent contrast with the gradual fall in the town's economical role in the Mediterranean. Pomp and magnificence of retinues was a constant of Imperial Istanbul. Tombs and mausoleums were an important psychological and politically effective component of Ottoman mentality. Keywords: Edirne; Istanbul; mausoleums; Mediterranean; Ottoman; seventeenth century; Tombs

Recently, network operators around the world have encountered a paradox. On the one hand, they have made enormous investments to handle the tremendous growth of Internet media services triggered by the ubiquitous penetration of high-speed wireless networks and the increasing popularity of mobile devices. On the other hand, these investments have not delivered the expected revenue, leading to declining profitability. In response to this paradox, network function virtualization (NFV) has been proposed as a revolutionary technology to transform network architecture and operations. This emerging technology opens up significant opportunities to reduce the cost of operating media services. In this article, the authors present a survey on this emerging topic. Specifically, they analyze the forces driving the evolution of the network architecture, then describe a novel NFV-enabled media cloud system from two alternative perspectives: an end-to-end view and a layered view. They then illustrate the architectural changes' technical challenges, which range from optimal resource provision and request routing to automated optimization. Finally, they substantiate the NFV-enabled media cloud platform with proof-of-concept case studies. By demonstrating NFV's flexibility and effectiveness, they show that the cost of providing Internet media services by NFV-enabled systems could be substantially reduced in practice.

Computer vision is becoming an increasingly trendy word in the area of image processing. With the emergence of computer vision applications, there is a significant demand to recognize objects automatically. Deep CNN (convolution neural network) has benefited the computer vision community by producing excellent results in video processing, object recognition, picture classification and segmentation, natural language processing, speech recognition, and many other fields. Furthermore, the introduction of large amounts of data and readily available hardware has opened new avenues for CNN study. Several inspirational concepts for the progress of CNN have been investigated, including alternative activation functions, regularization, parameter optimization, and architectural advances. Furthermore, achieving innovations in architecture results in a tremendous enhancement in the capacity of the deep CNN. Significant emphasis has been given to leveraging channel and spatial information, with a depth of architecture and information processing via multi-path. This survey paper focuses mainly on the primary taxonomy and newly released deep CNN architectures, and it divides numerous recent developments in CNN architectures into eight groups. Spatial exploitation, multi-path, depth, breadth, dimension, channel boosting, feature-map exploitation, and attention-based CNN are the eight categories. The main contribution of this manuscript is in comparing various architectural evolutions in CNN by its architectural change, strengths, and weaknesses. Besides, it also includes an explanation of the CNN’s components, the strengths and weaknesses of various CNN variants, research gap or open challenges, CNN applications, and the future research direction.