A lightweight and distributed middleware to provide presence awareness in mobile ubiquitous systems

Several researchers have identified the need to count on presence awareness in ubiquitous systems that support mobile activities, particularly when these systems are used to perform loosely-coupled mobile work. In such a work style, mobile users conduct face-to-face on-demand interactions, therefore counting on awareness information about the position and availability of potential collaborators becomes mandatory for these applications. Most proposed solutions that provide user presence awareness involve centralized components, have reusability limitations, or simply address a part of that service. This article presents a lightweight and fully distributed middleware named Moware, which allows developers to embed presence awareness services in mobile ubiquitous systems in a simple way. The article also describes the Moware architecture, its main components and strategies used to deal with several aspects of the presence awareness support. These design strategies can be reused by software designers to provide presence awareness capabilities into middleware and specific software applications. Moware services were embedded in a mobile ubiquitous system that supports inspectors during the construction inspection process. The preliminary results indicate that the middleware was easy to use for developers, and its services were useful for the end-users.     

一种中间件服务容错配置管理方法

提出一种基于运行时刻软件体系结构的容错管理方法,支持开发者和管理员针对不同中间件服务失效定制合适的故障检测和修复机制.首先,运行时刻软件体系结构自动构造构件依赖视图和错误传播①视图,为理解和分析整个系统的可靠性提供全局视图;然后,操作运行时刻软件体系结构配置容错机制;最后利用AOP技术将容错机制插装到中间件中,使其具备指定的容错能力.上述过程在一个可视化工具的辅助下半自动实施,并在J2EE中间件上得到验证.     

基于离散过程跟踪的自动识别处理中间件

为解决通用中间件与应用层缺乏关联的问题,提出一种基于离散过程跟踪的自动识别处理中间件。给出中间件的体系结构,设计数据计算服务算法,采用面向服务架构,提供数据读入接口,以此实现数据过滤、Web计算服务、数据访问适配器、消息事件等功能。实验结果表明,该中间件具有较好的适应性。     

Interactive middleware architecture for lifelog based context awareness

Due to the development of IT convergence, a wide variety of information is being produced and distributed rapidly in digital form. Lifelog based context awareness is a technology that provides a service automatically based on perceived situational information in ubiquitous environments. To offer customized services to users, the technology of acquiring lifelog based context information in real time is the most important consideration. We propose the interactive middleware architecture for lifelog based context awareness in distributed and ubiquitous environments. Conventional middleware to support ubiquitous environments stores and manages the situational information and service content acquired by centralized storage or a DBMS. Centralized situational information and service content management may impede the autonomy of mobile nodes and the interoperation between different middle software. The proposed method designs a system that can distribute and manage situational information in mobile nodes using mobile devices in distributed and ubiquitous environments and share the service content between interactive middleware through publication. The application system designed in this study was used in a scenario providing situational perception based mobile service and proved to be useful.     

中间件技术在移动增值领域的设计与实现

中间件是构件化软件的一种表现形式，中间件抽象了典型的应用模式。以一个移动增值平台为例，阐述构件化中间件系统的基本技术及在移动增值领域的应用。通过移动中间件在实际应用系统的具体设计与模块实现，设计一种基于数据库为中介的通用移动增值服务平台，并具体分析中问件满足快速开发和增强系统稳定性的优点，以及在增值领域开发还需要关注的问题。阐述了用移动中间件建立通用移动增值服务系统的必然性。     

软件体系结构驱动的运行环境

由于软件体系结构以隐性的方式存在，结构的问题被传播到平台内，运行时软件体系结构不能在应用层次上被观察和控制，系统难以联机动态演化．在现有的中间件平台之上设计了一个面向应用、开放的、软件体系结构驱动的分布式远行环境SADRE（Software Architecture—Driven Runtime Environment），软件体系结构在可运行系统中以一类实体显性地表示,体系结构描述作为核心元素被整个分布式运行环境共事，成为系统调度、通信的依据．从而驱动用户应用的运行．SADRE为灵活的动态体系结构提供了良好的支持，提高了系统的柔性和扩展性．     

Software architecture reliability analysis using failure scenarios

With the increasing size and complexity of software in embedded systems, software has now become a primary threat for the reliability. Several mature conventional reliability engineering techniques exist in literature but traditionally these have primarily addressed failures in hardware components and usually assume the availability of a running system. Software architecture analysis methods aim to analyze the quality of software-intensive system early at the software architecture design level and before a system is implemented. We propose a Software Architecture Reliability Analysis Approach (SARAH) that benefits from mature reliability engineering techniques and scenario-based software architecture analysis to provide an early software reliability analysis at the architecture design level. SARAH defines the notion of failure scenario model that is based on the Failure Modes and Effects Analysis method (FMEA) in the reliability engineering domain. The failure scenario model is applied to represent so-called failure scenarios that are utilized to derive fault tree sets (FTS). Fault tree sets are utilized to provide a severity analysis for the overall software architecture and the individual architectural elements. Despite conventional reliability analysis techniques which prioritize failures based on criteria such as safety concerns, in SARAH failure scenarios are prioritized based on severity from the end-user perspective. SARAH results in a failure analysis report that can be utilized to identify architectural tactics for improving the reliability of the software architecture. The approach is illustrated using an industrial case for analyzing reliability of the software architecture of the next release of a Digital TV.     

A middleware architecture for privacy protection

The issue of user privacy is constantly in spotlight since an ever increasing number of online services collects and processes personal information from users, in the context of personalized service provision. In fact, recent advances in mobile communications, location and sensing technologies and data processing are boosting the deployment of context-aware personalized services and the creation of smart environments; but at the same time, they pose a serious risk on individuals’ privacy rights. Although technology makes the collection of data easy, its protection against abuse is left to data protection legislation. However, the privacy requirements, other than being general and abstract terms to be regarded as legislature issues, should be brought down in technological reality and carefully accounted for in devising technical solutions. In order to limit the disclosure and avoid the misuse of personal data, this paper discusses an architectural proposal for a middleware system that will enforce protection of user privacy through technical means. The proposed architecture mediates between the users, the service providers and the law, constituting a middleware shield for individuals’ personal data.     

一种面向服务的权限管理模型

面向服务的体系结构(Service-Oriented Architecture,SOA)是设计和构建松耦合软件系统的方法,它可将基于中间件开发的分布式应用共享为Internet环境下的软件服务．传统中间件的用户权限系统具有较好的灵活性,基本满足封闭系统的安全需求．但在SOA模式下,难以满足不同节点和系统互相请求服务和共享资源过程中的授权．该文提出了一个面向服务的权限管理模型,通过支持用户之间的代理和提供一定的推理能力,为应用开发者提供了更完善的权限管理机制,并扩展了中间件跨越组织共享资源和服务的能力．该模型在一个J2EE应用服务器上被实现和验证．实验证明,该模型具有良好的灵活性和可扩展性,并且性能影响在合理的范围．     

机场信息集成系统设计

近几年来,中间件产业化速度发展很快,中间件软件已与操作系统、数据库并列为3大基础软件。民航业是较早进行信息化的行业之一,民航的应用已经从硬件的基础建设为主转向了软件应用服务为主。信息系统之间要求互联互通和信息共享,这对分布地域极广、信息系统众多的民航业来说,整合已经成为一种必然的趋势。该文从机场业务模型、系统软件结构、系统详细设计和对象互操作几方面,用面向对象的方法论述了机场信息集成系统的设计理念。     

从领域需求到产品线体系结构的映射——一种面向特征的方法

领域需求之间的依赖关系对软件产品线的体系结构有很大的影响,在已有的面向特征的管理产品线需求依赖的方法中很少有研究从需求到产品线体系结构的映射.基于一种特征依赖的分类方法,提出了从领域需求到特征,以及从特征到产品线体系结构的映射规则.通过这些映射规则,一致的需求通过映射得到一致的产品线核心资产,从而减少产品线中核心资产的不一致性并增加产品线的复用程度.用金融领域的现货交易产品线作为实例说明这个方法的实用性.     

An exploratory study of architectural effects on requirements decisions

The question of the “manner in which an existing software architecture affects requirements decision-making” is considered important in the research community; however, to our knowledge, this issue has not been scientifically explored. We do not know, for example, the characteristics of such architectural effects. This paper describes an exploratory study on this question. Specific types of architectural effects on requirements decisions are identified, as are different aspects of the architecture together with the extent of their effects. This paper gives quantitative measures and qualitative interpretation of the findings. The understanding gained from this study has several implications in the areas of: project planning and risk management, requirements engineering (RE) and software architecture (SA) technology, architecture evolution, tighter integration of RE and SA processes, and middleware in architectures. Furthermore, we describe several new hypotheses that have emerged from this study, that provide grounds for future empirical work. This study involved six RE teams (of university students), whose task was to elicit new requirements for upgrading a pre-existing banking software infrastructure. The data collected was based on a new meta-model for requirements decisions, which is a bi-product of this study.     

CHARMY: A Framework for Designing and Verifying Architectural Specifications

Introduced in the early stages of software development, the Charmy framework assists the software architect in making and evaluating architectural choices. Rarely, the software architecture of a system can be established once and forever. Most likely poorly defined and understood architectural constraints and requirements force the software architect to accept ambiguities and move forward to the construction of a suboptimal software architecture. Charmy aims to provide an easy and practical tool for supporting the iterative modeling and evaluation of software architectures. From an UML-based architectural design, an executable prototype is automatically created. Charmy simulation and model checking features help in understanding the functioning of the system and discovering potential inconsistencies of the design. When a satisfactory and stable software architecture is reached, Java code conforming to structural software architecture constraints is automatically generated through suitable transformations. The overall approach is tool supported.     

基于中间件的移动BOSS系统的设计与实现

自Client／server体系结构问世以来,中间件作为分布式网络上异构平台的互联桥梁应运而生,使用中间件进行大型应用系统的设计开发已经成为潮流。针对移动BOSS系统当前存在的一些问题,结合移动BOSS系统的结构和功能,设计并实现了基于中间件的4层体系结构的移动BOSS系统。系统增强了安全性、稳定性。     

支持扩展的自适应移动中间件模型及其设计

为了满足移动计算的要求,提高移动应用系统的扩展性和自适应性,移动中间件被引入到移动系统的开发中.分析了移动中间件必须满足的要求,提出了面向服务的移动中间件模型,该模型将分布在移动计算系统中的若干个中间件组织成中间件服务器来提高系统的扩展能力,介绍了该模型的体系结构及其设计,并对其性能进行了深入讨论.     

普适计算中间件技术

普适计算中间件通过软件基础设施重用支持上层应用的高效开发和便捷运行,是普适计算领域的研究热点。对普适计算中间件设计挑战进行了归纳,从上下文管理、中间件层自适应、面向自适应的公共服务和自适应软件体系结构支持等方面总结、阐述和分析了普适计算中间件的各项关键技术,分类介绍了主要普适计算中间件项目,给出了未来研究发展趋势。