A software architecture centric self-adaptation approach for Internetware

Being one of the basic features of Internetware, self-adaptation means that the software system can monitor its runtime state and behavior and adjust them when necessary according to pre-defined policies. Focusing on the three fundamental issues of self-adaptation, including the scope, operability and trustworthiness, a software architecture （SA） centric approach for Internetware＇s self-adaptation is presented in this paper. All of the self-adaptive actions, i.e. monitoring, analyzing, planning and executing, are performed based on SA. In detail, runtime state and behavior of Internetware are represented and changed in the form of runtime soft- ware architecture. The knowledge for self-adaptation is captured, organized and reasoned in the form of SA so that automatic analysis and decision-making are achieved.     

A software architecture centric engineering approach for Internetware

As a new software paradigm evolved by the Internet, Internetware brings many challenges for the traditional software development methods and techniques. Though architecture-based component composition (ABC) approach is originated in the traditional software paradigm, it supports the engineering of Internetware effectively due to its philosophy, rationales and mechanisms. ABC has three major contributions to the en- gineering of Internetware in detail. First, the feature oriented domain modeling method can structure the “disordered”“software entities” to “ordered Internetware” bottom-up in the problem space. Second, the architecture centric design and analysis method can support the development of self-adaptive Internetware. Third, the component operating platform is a reflective and self-adaptive middleware that not only provides Internetware with a pow- erful and flexible runtime infrastructure but also enables the self-adaptation of the structure and individual entities of Internetware.     

网构软件数据语用的一种动态支撑方法

网构软件不确定的数据需求导致了其数据语用(data pragmatics,简称DP)的不确定性,进而要求数据语用的支撑机制具备动态适应能力,即应用的对象属性与数据表之间的对应关系可以按需动态地创建、更新、删除.针对当前持久化技术缺乏数据语用的动态适应性问题,提出了一种基于对象/关系映射的数据语用动态支撑方法POD(persistence on demand),并且在主流ORM(object/relational mapping)框架的基础上实现了一个遵循POD的持久化框架的原型系统.     

支持协商的网构软件体系结构行为建模与验证

针对网构软件行为中的不确定性和不完整性,提出了一种支持协商的网构软件体系结构行为建模与验证方法.在建模中,该方法借鉴了UML时序图元素表示法,并增加了建模元素支持行为的不确定与不完整建模.在验证中,除了集成广泛应用的模型检查工具Spin以提供行为模型的验证能力以外,还引入了基于反例引导的抽象-精化过程思想的协商检查,以解决不确定和不完整建模所带来的正确性验证问题.     

用抽象质量类型构建高质量网构软件

在开发基于因特网的软件系统(文中称为网构软件)时,在开发过程的各个阶段都需要考虑软件系统的多种质量属性,这样网构软件的质量才能在软件系统的规约和设计阶段进行推导和预测,从而在部署和运行阶段进一步进行评估和验证。提出了一种新的抽象概念,即抽象质量类型,将软件实体的数据状态、相关的操作、质量属性以及保证质量得以实现的环境封装在一个统一的语法单元中,从而为建模软件实体以及推导其功能和非功能属性提供了一种严格的手段。探讨了基于软件体系结构及软件交互过程的抽象质量类型的组合,这为构建高质量网构软件提供了一定的形式化基础。最后,还描出了一个系统原型来展示如何利用抽象质量类型构造网构软件,并验证和提高网构软件系统的相关质量属性。     

On environment-driven software model for Internetware

Internetware is envisioned as a general software paradigm for the application style of resources integration and sharing in the open, dynamic and uncertain platforms such as the Internet. Continuing the agent-based Internetware model presented in a previous paper, in this paper, after an analysis of the behavioral patterns and the technical challenges of environment-driven applications, a software-structuring model is proposed for environment-driven Internetware applications. A series of explorations on the enabling techniques for the model, especially the modeling, management and utilization of context information are presented. Several proto-typical systems have also been built to prove the concepts and evaluate the techniques. These research efforts make a further step toward the Internetware paradigm by providing an initial framework for the construction of context-aware and self-adaptive software application systems in the open network environment.     

支持Internetware的中间件技术演化模型

随着网络的发展,中间件在应用的开发、部署和管理中扮演着越来越重要的角色。因为中间件的类型复杂,关于中间件的认知众说纷纭,而新一代计算环境和技术又对中间件提出了新的要求。针对中间件技术的演化提出了一种观点,并阐述了支持Internetware的下一代中间件系统的演化模型。     

基于Agent的软件体系结构研究

软件体系结构的使用是提高软件质量、减少软件开销和促进软件生产率提高的最有效方法之一,面向Agent技术的提出为复杂分布式问题的求解找到了办法.分析了软件体系结构和软件Agent技术的主要内容,提出基于Agent的软件体系结构,阐明了基于Agent的软件体系结构的总体结构及其在大型软件开发中的应用.     

特征模型驱动的网构软件构件组装与优化方法

面向特征的领域分析方法可为网构软件中资源的有序化提供有效支持.从领域工程的角度出发,提出一种特征模型驱动的网构软件组装与优化方法,该方法以iJackson图描述网构软件的特征模型,结合软件体系结构特点,分析了将特征模型转换为面向业务构件、基于工作流图技术的组合模型的机制,通过应用图论方法,将组合模型建模为以领域特征簇为中心的构件组装结构图,围绕面向多目标需求的QoS模型,建立了Internet环境下网构软件构件组装问题的数学模型,提出了一种基于蚁群优化算法的全局优化方法.最后,以网上书店系统为倒,介绍了仿真实验过程,并说明了方法的有效性和可行性.     

基于Agent的网构软件构件模型及其实现

网构软件代表了Internet环境下的一种新型的软件形态,但仍然面临着外部环境显式化、软件实体主体化、运行机制自适应等问题.从构件的角度出发,提出了EBDI(electronic business document exchange)结构以表示能够根据环境变化实施自主行为的构件,利用动态绑定关系解释了构件的自适应演化特征.根据形式化的Role模型,描述了构件的运行状态、自主运行及自适应演化运行机制.开发了DAgent-Internetware原型作为网构软件的支撑平台,支持以DAgent为构件的网构软件从设计到实现、部署、运行、演化等一系列流程.     

Software Evolution for Moving into and Moving within Internetware Paradigm

Internetware has been an emerging software paradigm to best support computing in the Internet era. Internetware emphasises accommodating the open, dynamic and uncontrollable natures of Internet, which directly and indirectly relates software evolvability. This paper observes that evolving non-Internetware software into the Internetware paradigm and evolving software within Internetware will be two main research and practical issues, and hence proposes an integrated approach to address these two issues. The proposed framework is based a three-dimension structure, with System Functions, System Quality and System models as dimensions. With this framework, evolving software into internetware paradigm can be viewed mainly as changing the qualities of existing software and evolving software within Internetware paradigm can be viewed mainly as changing software functions. The involved prototype tool, working examples and experiments conducted, are used to illustrate the proposed approach.     

Model‐centric software architecture reconstruction

Much progress has been achieved in defining methods, techniques, and tools for software architecture reconstruction (SAR). However, less progress has been achieved in constructing reasoning frameworks from existing systems that support organizations in architecture analysis and design decisions. These reasoning frameworks are necessary, for example, to assemble existing components and deploy them in new system configurations. We propose a model‐centric approach where this kind of reasoning is driven by the analysis of quality attribute scenarios. The scenarios and the related quality attribute models guide the SAR effort by focusing on the elicitation of model relevant artifacts. The approach further drives the model construction towards the analytical support of What If scenarios that explore responses stimulated by new requirements, such as new deployments of existing components. The paper provides two real‐world case studies. The first case study introduces the model‐centric reconstruction approach in the context of a large satellite tracking system. The second case study provides the construction of a time performance model for an existing embedded system in the automotive industry. The model allows us to perform cost‐efficient predictions of component assemblies in new customer configurations. Copyright © 2005 John Wiley & Sons, Ltd.     

一种面向网构软件体系结构的信任驱动服务选取机制

基于信任度评估的思想,从软件服务选取的角度对此问题进行了探讨,提出一种面向网构软件体系结构的信任驱动的服务选取机制:首先,给出一种通用的、机器可理解的应用需求及信任演化策略描述规范;其次,采用一种基于反馈的信任形成及决策机制,并给出一个信任驱动的服务选取算法;最后,给出一种面向网构软件体系结构的信任驱动的服务选取支撑框架.初步实践表明,上述机制为开发可信网构软件提供了有效支持.     

Runtime software architecture based on reflective middleware

Copyright by Science in China Press 2004 Since its first literate identification and discussion[1], software architecture (SA) has become an important subfield of software engineering, receiving increasing attention from both academic and industrial communities. SA describes the gross structure of a software system with a collection of components, connectors and constraints[2]. In gen-eral, SA acts as a bridge between requirements and implementation and provides a blue-print for system cons…     

基于构件的网构软件系统动态演化

为适应网构软件系统在线演化的需求,提出一种基于构件的网构软件系统动态演化模型。该模型以构件为基本单位,基于软件体系结构部署和实施演化,给出构件添加、删除和替换需求的演化算法,通过引入一致性检查机制保证演化的安全和可靠。该模型实施简单、具有普遍适用性,软件系统无须进行大量的改动即可适应该演化模型。     

基于软件体系结构的可复用构件模型

在分析了构件间各种操作的基础上,将软件体系结构的概念引入现有的构件模型,用于对复合构件进行描述,从而改进了现有的构件模型,给出了一种基于软件体系结构的可复用构件模型,并给出了该模型的应用.     

Internet计算环境下的新型软件形态——网构软件(Internetware)综述

软件形态受到应用、平台和技术发展的影响而不断演化。由于Internet这一新的计算环境的普及,传统的软件形态逐渐无法适应Internet环境下的开发和应用,需要研究新的软件形态和软件技术。该文在分析软件发展历史的基础上结合相关研究说明了基于Internet环境的网构软件(Internetware)是未来软件的发展趋势,介绍了网构软件的基本特征,并说明了网构软件领域的研究问题。     

面向构件的门诊部信息管理系统软件架构

构件化软件的设计集中于软件体系结构设计,其最主要的特征在于目标系统由大量可复用构件组成,这就要求在设计阶段应当设计出满足需求的软件体系结构。以一个门诊部信息管理系统软件架构为例,介绍了面向构件的软件架构方法,并对系统架构选型进行分析,提出了本系统的软件架构,为基于构件技术的系统实现提供良好的依据。