【作者】 唐丽；

【导师】 赵强；

【作者基本信息】 中国工程物理研究院北京研究生部 ， 计算机应用技术， 2002， 硕士

【摘要】 进入90年代以后，分布式计算结构开始从两层向多层转化，客户机和服务器之间的界限也日渐模糊。传统的客户/服务器结构已经无法适合于分布式计算环境。分布式对象技术的出现，为解决这一问题提出了新的有效途径。分布式对象技术是近年来飞速发展的一种软件技术，该技术允许不同机器上的对象可以相互传递消息。对象可以扮演客户及服务器的双重角色。 分布式对象技术旨在建立一种开放式的“软件总线”结构，任何应用作为一个对象，只要遵守一定的规则对其接口参数进行定义和说明，就可以接到软件总线上，发出请求或提供服务，达到即插即用的效果。 本文首先对分布式对象技术的出现、概念与三大流派(CORBA、COM／DCOM和Java／RMI)做了简要概述。然后，对CORBA标准规范进行着重介绍，并通过对CORBA的机构灵活性、软硬件平台无关性、系统可扩展性等优点的深入分析，论证了CORBA是目前解决分布式系统开发时所面临的跨平台、跨操作系统、跨语言、跨协议、跨版本等一系列问题的优化方案，是构建软件总线结构的首选标准。 本文以神光Ⅲ原型装置分布式控制系统为背景，针对该系统独特的体系结构和复杂的分布式通信需求，提出了“软件总线”这种开放性的分布式软件体系结构解决方案。然后，依照CORBA标准规范，重点对软件总线的可靠性及接口进行了分析与设计，并以C++ Builder为开发工具，实现了一条以ORB为支撑环境、通信中间件系统为核心的软件总线原型。这条软件总线的核心部分——通信中间件系统包含一套完整的消息通信协议和一组功能完善的用户接口函数，可方便、可靠、快速地实现分布式异构环境下不同软件模块间的通信和协同工作。此外，该系统还具有独立于网络地址、计算机物理位置、操作系统、硬件平台、编程环境及工具等特点，从而有效地解决了系统集成时所面临的应用互操作性等问题。更多还原

【Abstract】 Since 1990’s,distributed computing architecture began to transform into multi-tier from two-tier,and the borderline between client and server is ambiguous increasingly.Traditional client/server architecture can not be adapted to distributed computing environments.Distributed object technology can solve the problem. Distributed object technology develops quickly in recent years,which allows objects on different machines to communicate messages to each other.The major idea of distributed object technology is to set up an open software bus. Any application can be viewed as a distributed object.lt can be plugged into the software bus,bring forward requests or provide service ,and accomplish true "plug-and-play" as long as its interface parameters are defined according to some standards.The appearance,concept and primary genres(CORBA COM/DCOM and Java/RMI) of distributed object technology are discribed in brief ,and then CORE A specification is discussed in detail in this paper.The advantages of CORBA,such as flexibility,platform-independent and extensibility,are analyzed in depth.These analysises demonstrate that CORBA is the best scheme to solve the problems such as cross-platform,cross-operation system,cross-language,cross-protocol and cross-edition in distributed systems,and CORBA is the principal specification to construct a software bus.Background of this paper is TILICS.Because of the particular architecture and complex communication requirements in distributed environments of TILICS,a scheme provided with an open distributed software architecture,namely "software bus" is proposed. According to CORBA,the dependability and the interface of software bus is analyzed and designed ,and then a software bus which is based on ORB and has a communication middleware system as the core is implemented by C++ Builder.The core of the sotfware bus,communication middleware system,consists of a suit of integrated communication protocols and a set of perfect interface functions,which can make disparate software modules communicate and collaborate with each other in distributed heterogeneous environments.This system is also independent of network address,computer location,operation system,hardware platforrn,programming environment and development tool,so it can solve the problems such as interoperability in system integration effectively.更多还原