基于上下文的移动Web Services

文章为Web Services提出移动环境中的优化方案———基于上下文的移动Web Services。根据获得的客户端的上下文信息处理SOAP消息,得到精确的结果;上下文类型的扩展无需根据下层结构的差异进行修改。由基于上下文的Web Services或Context Services处理请求,减少带宽消耗,优化信息供应,以满足移动通讯的要求。     

基于优化逆问题的Web服务选择

为提高服务提供商的服务被选率,将优化逆问题应用到Web服务选择领域,提出了Web服务选择优化逆问题,描述了此问题的解决步骤,比较了割平面法和Huang法的优劣,给出了改进方法.为提高Web服务选择优化的求解效率和优度,基于Web服务选择优化逆问题,设计出Web服务选择优化算法--逆选择算法,为服务请求者提供最优或近似最...     

一种基于语义的RESTful Web服务匹配模型

RESTful Web服务是一种轻量级分布式的系统架构,能满足不同系统开发的需要?为了能够自动有效地发现用户所需要的RESTfub Web服务,在一种有效匹配算法的基础上,通过hRESTS和MicroWSMO 2种微格式对RESTful Web服务的超文本标记语言(hypertext markup language,HTML)文档信息进行语义描述,构建匹配模型?该模型包括了本体?匹配引擎?提取器等模块,这些模块具有不同的功能,可以将服务请求方的请求条件和服务提供方提供的参数进行语义上的匹配,进而来发现服务?经过实验证明,该基于语义的RESTful Web服务匹配模型在效率指标方面较现有匹配模型有较大的提高?     

Design and implementation of Web services security based on message layer

Along with the development of internet, Web Services technology is a new branch of Web application program. and it has become a hotspot in computer science. However, it has not made great progress in research on Web Services security. Traditional security solutions cannot satisfy the Web Services security require of selective protection, endto-end security and application layer security. Web Services technology needs a solution integrated in Web Services frame work to realize end tc~end security. Based on cryptography and Web Services technology and according to W3C, XML encryption specification, XMI. digital Signature specification and WS-Security, which proposed by IBM and Microsoft. a new Web services security model based on message layer is put forward in this paper. The message layer is composed of message handlers. It is inserted into the message processing sequence and provides transparent security services for Web Services. To verify the model, a Web Services security systern is realized on . net platform. The implementation version of the model can provide various security services, and has advantages such as security, scalability, security controllability and end-to-end security in message level.     

可信Web服务的度量模型

针对Web服务的可信性缺乏有效度量方法的问题,引用本体的基本思想和主要理论对Web服务进行统一的语义描述和建模,提出了可信Web服务的度量模型(MM-TWS),建立了面向本体的可信Web服务,并解析了MM-TWS中建立本体的基本步骤和主要流程。采用模糊描述逻辑来设计MM-TWS的模型算法FDL-MM-TWS,并推算Web服务的可信度。最后,利用MM-TWS对一个基于突发事件处理的智能建筑系统集成进行度量,初步验证了该方法的可行性和有效性。     

Abstract model checking for Web services

Web-services are highly distributed programs, and concurrent software is notoriously error-prone. Model checking is a powerful technique to find bugs in concurrent systems. However, the existing model checkers have no enough ability to support for the programming languages and communication mechanisms used for Web services. We propose to use Kripke structures as means of modeling Web service. This paper presents an automated way to extract formal models from programs implementing Web services using predicate abstraction for abstract model checking. The abstract models are checked by means of a model checker that implements automatic abstraction refinement. These results enable the verification of the applications that implement Web services.     

Web服务的一种通用集成模型的研究

提出了一种Web服务集成的通用模型GIMWS,它使用一种面向服务的多层体系结构,该模型将异构Web服务的同化和事务合成分离开,有效地解决了Web服务间的异构问题,扩展了分布事务管理的两阶段提交协议2PC以增强集成得到的Web服务的健壮性和适应性,为大量Web服务的高效集成提供了一种通用机制．     

基于图论的Web服务合成算法

研究了Web服务合成问题,解决该问题的关键是对候选Web服务的输入输出数据关系进行建模,以及有效地利用这些已有的数据依赖关系实现服务合成请求.通过从Web服务规范语言中提取Web服务的语义信息,构建Web服务的依赖图;提出了一种基于搜索算法的Web服务合成算法,获取满足特定服务请求的Web服务合成.     

基于Web services的信息服务系统设计与实现

Web services是一种新型的分布计算技术，是解决传统中间件技术问题的重要方法。信息服务是Web services软件框架的重要组成部分，它为分布环境中信息的有效处理奠定了重要的基础。本文从介绍Web services中信息服务系统的基本内容入手，并以此为基础设计了信息服务系统，论述了信息服务系统的功能、特点和执行过程。最后，对基于Web services的信息服务系统进行评价并指出了今后的研究方向。     

Automatic Web services composition based on SLM

Motivated by the problem of simplifying the manual operation of the composition process, we propose an approach to automatically compose available Web services to fulfill user＇s goal based on the assumption that there are a set of alternative Web services with similar functionality and different QoS properties. A formal model （i.e. semantic links matrix, SLM for short ） is proposed to store semantic links values for the Web services with semantic relationship and QoS of Web services. The SLM provides a search place for a backward-search planning algorithm, at the same time; the QoS criteria make a rational and effective decision among a number of similar Web services. The function and some properties of the algorithm are analyzed. The approach can improve the correctness and flexibility for Web services composition and satisfy the local QoS attribute.     

基于扩展QoS模型的物流服务选择方法

随着越来越多的物流公司开始采用Web服务技术提供服务,如何从大量具有相似功能的服务中选出最能满足特定业务需求的物流服务变得日益重要。已有的研究大多局限于通用的Web服务选择,难以满足特定业务领域的选择需求。为了解决该问题,该文通过引入物流业务服务质量指标,构建了一个基于层次分析法(analytic hierarchy process,AHP)框架的服务质量(quality of service,QoS)扩展模型,并在此基础上提出了一种新的物流服务选择方法,综合运用分层聚类算法和模糊综合评判的方法对候选物流服务进行选择。最后,在重庆港物流项目中进行了实际验证,结果证明该方法能够有效地根据特定业务需求选择出最适合的物流服务。     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining, the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Web服务的多层入侵容忍机制

Web服务通过互联网向公众提供各种服务,其存在的漏洞容易受到攻击.攻击会导致许多恶意操作或故障,致使Web服务器无法正常工作或发生安全事件.确保服务器的安全性,以保障系统数据和服务的私密性、完整性及可用性.Web服务的多层入侵容忍机制,结合传统安全技术和容忍技术在服务器前和在服务器结构内部署不同传感器,侦测各请求对服务器的影响.对不同安全级别的请求提供相应的服务,并一定程度上容忍非正常请求的存在.在Web服务系统上提供有效的深度防御,提高Web服务器对入侵、攻击的适应能力,即使发生严重事件也能及时恢复Web服务.不会因存在入侵、故障而停止服务,从而提高Web服务器的生存能力.     

Fair non-repudiation for web services transactions

To safeguard the interests of transacting parties, non-repudiation mechanisms need to assure fairness and timeliness. The non-repudiation service currently implemented usually does not consider the requirement of fairness and the fair non-repudiation protocols to date can not be suitably applied in real environment due to its complex interaction. This paper discusses the transaction-oriented non-repudiation requirement for Web services transaction, analyzes the constraints of the traditional model for the available fair non-repudiation protocols and designs a new Online-TTP fair non-repudiation protocol. The new protocol provides a fair non-repudiation solution to secure Web services transactions and can be embedded into a single Web service call. The protocol adopts evidence chained to decreasing the overhead of evidence verification and management and alleviates the overhead of certificate revocation checking and time-stamp generation for signatures. The protocol has strong fairness, timeliness, efficiency and practicability.     

新一代网络计算模式Web服务

基于Internet标准协议的Web服务技术的出现,突破了传统分布式计算技术难以穿越防火墙的缺点,因而可用于集成 Internet上的各种服务,实现 Internet范围内跨平台、跨操作系统的分布式计算.文章介绍了构成 Web服务体系架构的主要标准和协议简单对象访问协议(SOAP)、Web服务描述语言(WSDL)和统一描述、发现和集成协议(UDDI),并给出示例参考代码和Web服务具体应用的实例.     

Activity sequence modes for Web services and verifications

Behavior requirement expression and its satisfiability verification for composite Web services is one of the ongoing issues in service computing.In this paper,the concept of behavior specifications based on activity sequence is proposed to express one kind of behavioral requirements for composite Web services.Its basic element is activity sequence.The method to express such behavioral requirements by behavioral modes is presented.Five behavioral modes used in this method are adopted.Through mapping modes to Labeled Transition Systems(LTSs),these modes are encoded with exact operation semantics.Then,the sufficient and necessary conditions as well as the checking algorithm for satisfiability of behavioral modes are given.Finally,an example analysis is presented.The result indicates that the behavioral requirements based on activity sequence are more suitable for the case of composite Web service than those based on activity or scenario.The behavioral modes expressions are concise and the satisfiability checking is effective by the given algorithm.     

基于DOTNET的Web服务技术和实现

Web服务是一种新的分布式技术,它建立在互联网和组件的基础上,解决了分布式技术COM和CORBA所不能解决的问题.文章首先介绍了Web服务技术的结构,详细说明了它的标准协议XML 、SOAP、 WSDL 和UDDI,然后阐述在DOTNET的平台上实现Web服务的2种方式和基于DOTNET的Web服务的特点,最后预测了Web服务的未来发展.