Integration of transient Web services into a virtual peer to peer Web service registry

Transient Web service provisioning implies a variety of different requirements that are hard to meet in traditional Web service environments. Currently, Web service brokerage focuses on centralized or replicated architectures. We argue that such systems are not efficient when it comes to dynamic, respectively ad hoc, Web service provisioning. We propose a distributed peer to peer Web service registry solution based on lightweight Web service profiles. We further introduce the notion of views that allow the specification of arbitrary contexts of Web services and provide a working example to illustrate our approach. Finally, we present a prototype that uses tuple spaces as global storage and communication means.     

Toward Quality-Driven Web Service Discovery

Service-oriented architectures follow the find-bind-execute paradigm, in which service providers register their services in public or private registries, which clients use to locate Web services. If a service registry has information on a service that matches a client's criteria, it provides a contract and an access point. Web service discovery is a key component in service-oriented computing. However, without Web service quality standards and quality-based discovery mechanisms, the trustworthiness of business-to-business interactions can't be guaranteed.     

基于语义的Web服务注册联邦的研究

元模型互操作框架是一套元对象和元模型结构的集合．用于信息注册和信息资源库开发中元模型的建立．将元模型互操作框架MMFI与联邦信息管理技术结合．运用表体元建模方法，建立Web服务注册联邦的体系结构，以实现异构自治的Web服务注册问可扩展的语义互操作．提出表体对象建模理论和方法，指导Web服务注册联邦系统的开发设计，简化设计开发过程．介绍了一个依据上述方法建立的软构件注册平台的原型系统．     

Discovering Web Services in Search Engines

Web service access points are no longer a scarce resource, and the process of discovering them is no longer attached to service registries as Web search engines have become a new major source for Web services. Unfortunately, these separate but distinct approaches to service discovery make it unclear whether provisional registry specifications and search-engine technologies will eventually emerge or coexist.     

METEOR-S WSDI: A Scalable P2P Infrastructure of Registries for Semantic Publication and Discovery of Web Services

Web services are the new paradigm for distributed computing. They have much to offer towards interoperability of applications and integration of large scale distributed systems. To make Web services accessible to users, service providers use Web service registries to publish them. Current infrastructure of registries requires replication of all Web service publications in all Universal Business Registries. Large growth in number of Web services as well as the growth in the number of registries would make this replication impractical. In addition, the current Web service discovery mechanism is inefficient, as it does not support discovery based on the capabilities of the services, leading to a lot of irrelevant matches. Semantic discovery or matching of services is a promising approach to address this challenge. In this paper, we present a scalable, high performance environment for Web service publication and discovery among multiple registries. This work uses an ontology-based approach to organize registries into domains, enabling domain based classification of all Web services. Each of these registries supports semantic publication and discovery of Web services. We believe that the semantic approach suggested in this paper will significantly improve Web service publication and discovery involving a large number of registries. This paper describes the implementation and architecture of the METEOR-S Web Service Discovery Infrastructure, which leverages peer-to-peer computing as a scalable solution.     

WSB: a broker‐centric framework for quality‐driven web service discovery

Web service interfaces can be discovered through several means, including service registries, search engines, service portals, and peer‐to‐peer networks. But discovering Web services in such heterogeneous environments is becoming a challenging task and raises several concerns, such as performance, reliability, and robustness. In this paper, we introduce the Web Service Broker (WSB) framework that provides a universal access point for discovering Web services. WSB uses a crawler to collect the plurality of Web services disseminated throughout the Web, continuously monitor the behavior of Web services in delivering the expected functionality, and enable clients to articulate service queries tailored to their needs. The framework features ranking algorithms we have developed which are capable of ranking services according to Quality of Web Service parameters. WSB can be seamlessly integrated into the existing service‐oriented architectures. Copyright © 2010 John Wiley & Sons, Ltd.     

Web services lookup: a matchmaker experiment

UDDI is a standard registry for Web services, but so far its search functionality has been limited to keyword search. These authors propose a UDDI enhancement called Matchmaker, which supports semantic service capability discovery. Since September 2003, they have deployed Matchmaker in one of four official UDDI registries operated by NTT-Communications. In this article, they introduce Matchmaker and illustrate client tools that lower the threshold for using semantics in service discovery. Experiments show that Matchmaker search consumes about 5 seconds more time than a typical keyword-based search. The authors also collected user information through questionnaires and by observation of search behavior.     

基于Web Service架构的新闻服务研究

Internet特有的时效性,使得网络新闻出版和服务正在步入一个快车道。尽管基于HTTP/HTML架构的Web新闻服务方式在新闻的时空性方面超越了传统媒体,但它的交互性还不足以满足个性化新闻定制和阅读的需求。该文提出了一种基于WebService架构和NewsML置标语言的新闻服务系统框架,讨论了新闻服务提供端、新闻注册端和新闻发现/阅读客户端的工作原理和关键技术。基于WebService架构和新闻语言NewsML的新闻服务系统,支持个性化的新闻定制和服务。     

一种基于访问控制的安全Web服务发现机制

当前的Web服务发现机制大多依赖集中式的统一描述、发现和集成注册中心,但组织机构出于安全和地域的考虑,倾向于构建私有的分布式注册中心,只有注册且可信的请求者才能浏览到他们有权限访问的服务信息。该文给出Web服务发现阶段基于角色的访问控制模型RBAC4WSD,发现代理依照服务提供者指定的安全策略对请求者实施访问控制,并以跨国公司内部的文档服务为例介绍原型系统的实现。     

一种基于P2P的语义Web服务发布和发现模型

服务发布和发现是Web服务应用中极其重要的环节.随着Web服务数目的增长和对实时性需求的增加,分布式服务发布和发现机制成为Web服务应用的一个新研究方向.对当前Web服务发现问题研究进行了探讨,提出了基于P2P的Web服务发布和发现的工作模型,并以实例说明了其工作过程.该模型采用两层结构:第一层是纯Peer-Peer连接,通过一定的路由机制保证通信的畅通,有效地支持系统的可扩展性;第二层采用集中式的连接方式,各个Peer节点集中连接到指定的Broker,以方便统一管理和维护,提高系统的查询效率.     

一种基于P2P的语义Web服务发布和发现模型

服务发布和发现是Web服务应用中极其重要的环节。随着Web服务数目的增长和对实时性需求的增加,分布式服务发布和发现机制成为Web服务应用的一个新研究方向。对当前Web服务发现问题研究进行了探讨,提出了基于P2P的Web服务发布和发现的工作模型,并以实例说明了其工作过程。该模型采用两层结构：第一层是纯Peer—Peer连接,通过一定的路由机制保证通信的畅通,有效地支持系统的可扩展性;第二层采用集中式的连接方式,各个Peer节点集中连接到指定的Broker,以方便统一管理和维护,提高系统的查询效率。     

LinkedWS: A novel Web services discovery model based on the Metaphor of “social networks”

Web services are increasingly becoming the de facto implementation for the service-oriented architecture paradigm for enterprises due to their ease of use. Nevertheless, discovering these Web services is still hindered by many challenges that are partially attributed to shortcomings found in the discovery registry models (e.g., UDDI) used nowadays. These registries do not, for example, capture the rich information resulting from the various types of interactions between Web services. To address these shortcomings, and inspired by the conventional human social networks on the net, like Facebook and Twitter, we develop LinkedWS, a social networks discovery model to capture the different interactions that occur between Web services. Based on these interactions, specialized relationships are spawned and discerned. Examples of these relationships are collaboration and substitution. This paper describes LinkedWS and its potential, and reports on its implementation status.     

A structural-semantic web service selection approach to improve retrievability of web services

Service-Oriented Computing promotes building applications by consuming and reusing Web Services. However, the selection of adequate Web Services given a client application is still a major challenge. The effort of assessing and adapting candidate services could be overwhelming due to the “impedance” of Web Service interfaces expected by clients versus the actual interfaces of retrieved Web Services. In this work, we present a novel structural-semantic approach to help developers in the retrieval and selection of services from a service registry. The approach is based on a comprehensive structural scheme for service Interface Compatibility analysis, and WordNet as the semantic support to assess identifiers of operations and parameters. We also empirically analyze, compare and contrast the performance of three service selection methods: a pure structural approach, a pure semantic approach, and the structural-semantic (hybrid) approach proposed in this work. The experimental analysis was performed with two data-sets of real-world Web Services and a service discovery support already published in the literature. Results show that our hybrid service selection approach improved effectiveness in terms of retrievability of Web Services compared to the other approaches.     

基于信誉模型的Web服务优化选择

随着Web服务技术的发展与广泛应用,提供相同功能的Web服务越来越多,而如何在其所提供的Web服务中选择最优服务成为关键问题.传统的基于服务质量(QoS)模型的选择方案已不能满足此要求.提出了一种基于信誉模型并结合QoS的优化选择方案,首先利用工作流组织模型确定服务使用者之间的信任度结,结合可信用户的反馈评价值,确定服务的主观信誉度,然后根据Web服务的QoS量化模型,计算出客观质量值,最后结合二者选出最优的服务.