Invocation Of Web Services Research Articles

CONTEMPORARY SEMANTIC WEB SERVICE FRAMEWORKS: AN OVERVIEW AND COMPARISONS

The growing proliferation of distributed information systems, allows organizations to offer their business processes to a worldwide audience through Web services. Semantic Web services have emerged as a means to achieve the vision of automatic discovery, selection, composition, and invocation of Web services by encoding the specifications of these software components in an unambiguous and machine-interpretable form. Several frameworks have been devised as enabling technologies for Semantic Web services. In this paper, we survey the prominent Semantic Web service frameworks. In addition, a set of criteria is identified and the discussed frameworks are evaluated and compared with respect to these criteria. Knowing the strengths and weaknesses of the Semantic Web service frameworks can help researchers to utilize the most appropriate one according to their needs.

Contemporary Semantic Web Service Frameworks: An Overview and Comparisons

The growing proliferation of distributed information systems, allows organizations to offer their business processes to a worldwide audience through Web services. Semantic Web services have emerged as a means to achieve the vision of automatic discovery, selection, composition, and invocation of Web services by encoding the specifications of these software components in an unambiguous and machine-interpretable form. Several frameworks have been devised as enabling technologies for Semantic Web services. In this paper, we survey the prominent Semantic Web service frameworks. In addition, a set of criteria is identified and the discussed frameworks are evaluated and compared with respect to these criteria. Knowing the strengths and weaknesses of the Semantic Web service frameworks can help researchers to utilize the most appropriate one according to their needs.

Service-oriented computing with wireless participants

No abstract available.

Integrating trust management and access control in data-intensive Web applications

The widespread diffusion of Web-based services provided by public and private organizations emphasizes the need for a flexible solution for protecting the information accessible through Web applications. A promising approach is represented by credential-based access control and trust management. However, although much research has been done and several proposals exist, a clear obstacle to the realization of their benefits in data-intensive Web applications is represented by the lack of adequate support in the DBMSs. As a matter of fact, DBMSs are often responsible for the management of most of the information that is accessed using a Web browser or a Web service invocation. In this article, we aim at eliminating this gap, and present an approach integrating trust management with the access control of the DBMS. We propose a trust model with a SQL syntax and illustrate an algorithm for the efficient verification of a delegation path for certificates. Our solution nicely complements current trust management proposals allowing the efficient realization of the services of an advanced trust management model within current relational DBMSs. An important benefit of our approach lies in its potential for a robust end-to-end design of security for personal data in Web scenario, where vulnerabilities of Web applications cannot be used to violate the protection of the data residing on the database server. We also illustrate the implementation of our approach within an open-source DBMS discussing design choices and performance impact.

Lightweight Wireless Web Service Communication Through Enhanced Caching Mechanisms

Reducing the size of the wirelessly transmitted data during the invocation of third-party Web services is a worthwhile goal of many mobile application developers. Among many adaptation mechanisms that can be used for the mediation of such Web service invocations, the automated enhancement of caching mechanisms is a promising approach that can spare the re-transmission of entire content fields of the exchanged messages. However, it is usually impeded by technological constraints and by various other factors, such as the inherent risk of using responses that are not fresh, i.e., are not up-to-date. This paper presents the roadmap, the most important technical and algorithmic details, and a thorough evaluation of the first solution for generically and automatically enriching the communication with any third-party Web service in a way that cached responses can be exploited while a freshness of 100% is maintained.

A proxy-based architecture for dynamic discovery and invocation of web services from mobile devices

Mobile devices are getting more pervasive, and it is becoming increasingly necessary to integrate web services into applications that run on these devices. We introduce a novel approach for dynamically invoking web service methods from mobile devices with minimal user intervention that only involves entering a search phrase and values for the method parameters. The architecture overcomes technical challenges that involve consuming discovered services dynamically by introducing a man-in-the-middle (MIM) server that provides a web service whose responsibility is to discover needed services and build the client-side proxies at runtime. The architecture moves to the MIM server energy-consuming tasks that would otherwise run on the mobile device. Such tasks involve communication with servers over the Internet, XML-parsing of files, and on-the-fly compilation of source code. We perform extensive evaluations of the system performance to measure scalability as it relates to the capacity of the MIM server in handling mobile client requests, and device battery power savings resulting from delegating the service discovery tasks to the server.

CONTEMPORARY SEMANTIC WEB SERVICE FRAMEWORKS: AN OVERVIEW AND COMPARISONS

The growing proliferation of distributed information systems, allows organizations to offer their business processes to a worldwide audience through Web services. Semantic Web services have emerged as a means to achieve the vision of automatic discovery, selection, composition, and invocation of Web services by encoding the specifications of these software components in an unambiguous and machine-interpretable form. Several frameworks have been devised as enabling technologies for Semantic Web services. In this paper, we survey the prominent Semantic Web service frameworks. In addition, a set of criteria is identified and the discussed frameworks are evaluated and compared with respect to these criteria. Knowing the strengths and weaknesses of the Semantic Web service frameworks can help researchers to utilize the most appropriate one according to their needs.

Design Pattern for Feature-Oriented Service Injection and Composition of Web Services for Distributed Computing Systems with SOA

In the world of today's Enterprise Java Applications development, there is a need to support the principles of the Service Oriented Architecture (SOA). So in order to develop the SOA based applications any enterprise java developer should have the strong foundation in Java Web Services (JWS). As most of the leading enterprise java vendors feel that it's perfect to use the JWS technologies for the development of their SOA applications. In this paper we will propose a new design pattern in terms of Distributed application development, where we will be concentrating on the web services invocation and the composition of web services with the support of SOA. The paper will provide a perfect idea about how the amalgamation of Visitor Design Pattern and Case-Based Reasoning Design Pattern help us for the development of the Service Invocation and Web Services Composition through SOA with the help of JWS technologies. And also with the help of newly introduced programming models like Feature-Oriented Programming (FOP), it will be flexible for us to include the new service invocation function into the service providing server as a Feature Module. We have provided with the sample code that we have developed for the application in our paper. Here we will be using the Service Oriented Architecture (SOA) with Web Services in Java to Implement the Design Pattern. The pattern is described using a java-like notation for the classes and interfaces. A simple UML Class and Sequence diagrams are depicted.

Security Policy Configuration Analysis for Web Services on Heterogeneous Platforms

With the rapid development of web services, message security of web services between heterogeneous platforms is increasingly prominent. As two popular web services platforms, Apache Axis2 and Microsoft .Net, have their own security module respectively (Rampart, WSE). Due to differences in platform security mechanisms, it is difficult to build a secure web services communications between different platforms. This paper firstly introduces the Apache Axis2 and. Net platforms, and then analyzes their differences of security mechanism on these two platforms. Finally, followed by a typical secure case, a series of steps are designed and tested in order to realize secure web service invocation on heterogeneous platforms.

Flexible Service Composition Based on Bundle Communication in OSGi

Service provision and consumption platforms are more and more used to enable communication between sensors, actuators and intelligent devices, since they provide mechanisms that make possible the combination of components to create composed services. However, these kinds of platforms have limitations to adapt themselves to new and unknown devices. In this work we analyze the challenge of component or bundle communication by using the Open Services Gateway Initiative (OSGi) technology and we propose three mechanisms with the aim of contributing to flexible component communication: Common Service, Specific Service and WSIF Web Service Invocation. We provide these solutions with some architectural models and validate them through different example services. Finally we compare them regarding performance, flexibility and application complexity.

The Research and Application of Web Service Bridge Technology in Remote Web Service Invocation Based on ASP.NET AJAX

In this paper, we used web Service Bridge to solve the ASP.NET AJAX client cannot directly invoke the remote web service problem caused by the security restrictions of JavaScript. Web Service Bridge makes the AJAX client invoke the remote web services as if it invokes the local web services by defining the local service proxy for remote web service in XML declaration. The example demonstrates that, compared to the traditional method of programming local service proxy, web Service Bridge is more convenient and efficient to implement a large number of remote web service invocations in Mushup application.

On-demand service hosting on production grid infrastructures

The Software as a Service (SaaS) methodology is a key paradigm of Cloud computing. In this paper, we focus on an interesting topic--to dynamically host services on existing production Grid infrastructures. In general, production Grids normally employ a Job-Submission-Execution (JSE) model with rigid access interfaces. In this paper, we implement the Cyberaide onServe, a lightweight middleware with a virtual appliance. The Cyberaide onServe implements the SaaS model on production Grids by translating the SaaS model to the JSE model. The Cyberaide onServe can be deployed on demand in a virtual appliance, host users' software as a Web service, accept Web service invocations; finally, the Cyberaide onServe can execute them on production Grids. We have deployed the Cyberaide onServe on the TeraGrid and the test results show that the Cyberaide onServe can provide SaaS functionalities with a good performance.

A Generic QoS Model for Web

The development, registration, discovery, and invocation of quality Web services are vital for the successful implementation of applications using Web services. Considerable research focuses on quality for Web services. Unfortunately, current research on Quality of Service (QoS) for Web services is concentrated on service users and the implementation stage. This research highlights the importance of incorporating QoS at the design and development stages; the authors propose the introduction of QoS at the same time as functional requirements. However, Web Service Description Language (WSDL) describes the functional elements of a Web service, and QoS is significant for this description. Therefore, the authors propose an extension to the WSDL through a generic QoS metamodel, incorporating QoS specifications into the functionalities. This paper begins by defining the required QoS specifications for the development of quality Web services and explores the potential of the Unified Modeling Language as a technique and notation to specify QoS. To properly integrate QoS in the design, the authors propose extensions to the existing UML QoS profile. The paper concludes with the evaluation of the proposed framework and summarises its advantages.

WSMO and WSMX Support to the Semantic Web Services Technology

This paper tests the ability of the Web Service Modeling Ontology (WSMO) and the Web Service Modeling eXecution environment (WSMX) to support the Semantic Web Services technology, and automate the process of web service discovery, selection and invocation. First, it introduced web services and their limitations that were overcome in the vision of the Semantic Web Services technology. Then a Semantic Web Service (SWS) was built on top of WSMO to access the publications of the German University in Cairo (GUC), and was registered to WSMX. To test the validity to the claim, a service request to access the publications of the GUC was sent to WSMX and the process followed by WSMX was investigated. Furthermore, the discussion added a suggestion that would enhance the transparency between the Semantic Web and WSMO-WSMX initiatives.

QoS-Aware Web Service Recommendation by Collaborative Filtering

With increasing presence and adoption of Web services on the World Wide Web, Quality-of-Service (QoS) is becoming important for describing nonfunctional characteristics of Web services. In this paper, we present a collaborative filtering approach for predicting QoS values of Web services and making Web service recommendation by taking advantages of past usage experiences of service users. We first propose a user-collaborative mechanism for past Web service QoS information collection from different service users. Then, based on the collected QoS data, a collaborative filtering approach is designed to predict Web service QoS values. Finally, a prototype called WSRec is implemented by Java language and deployed to the Internet for conducting real-world experiments. To study the QoS value prediction accuracy of our approach, 1.5 millions Web service invocation results are collected from 150 service users in 24 countries on 100 real-world Web services in 22 countries. The experimental results show that our algorithm achieves better prediction accuracy than other approaches. Our Web service QoS data set is publicly released for future research.

A Flexible Tool for Web Service Selection in Service Oriented Architecture

Web Services are emerging technologies that enable application to application communication and reuse of services over Web. Semantic Web improves the quality of existing tasks, including Web services discovery, invocation, composition, monitoring, and recovery through describing Web services capabilities and content in a computer interpretable language. To provide most of the requested Web services, a Web service matchmaker is usually required. Web service matchmaking is the process of finding an appropriate provider for a requester through a middle agent. To provide the right service for the right user request, Quality of service (QoS)-based Web service selection is widely used. Employing QoS in Web service selection helps to satisfy user requirements through discovering the best service(s) in terms of the required QoS. Inspired by the mode of the Internet Web search engine, like Yahoo, Google, in this paper we provide a QoS-based service selection algorithm that is able to identify the best candidate semantic Web service(s) given the description of the requested service(s) and QoS criteria of user requirements. In addition, our proposed approach proposes a ranking method for those services. We also show how we employ data warehousing techniques to model the service selection problem. The proposed algorithm integrates traditional match making mechanism with data warehousing techniques. This integration of methodologies enables us to employ the historical preference of the user to provide better selection in future searches. The main result of the paper is a generic framework that is implemented to demonstrate the feasibility of the proposed algorithm for QoS-based Web application. Our presented experimental results show that the algorithm indeed performs well and increases the system reliability.

Self-adapting workflow reconfiguration

Because web services are highly interoperable, they are capable of providing uniform access to underlying technologies, allowing developers to choose between competing services. Workflow languages, such as BPEL, compose and sequence Web service invocations resulting in meaningful, and sometimes, repeated tasks. Their prevalence means there may be multiple Web services that perform the same operation with some better than others depending on the situation. Their potential for being unavailable at critical workflow execution times forces a reliance on such redundant services. One remedy for unavailability and situational awareness constraints is using quality of service factors and user-directed preferences to assign priorities to workflows and services to perform run-time replacement. In this paper we describe a novel approach to self-adapting workflow reconfiguration. We discuss the implementation of our approach embodied by the Next-generation Workflow Toolkit that supports runtime workflow reconfiguration using BPEL with a commercial workflow engine. A key design feature is the decoupling of user-directed changes regarding service priority from the actual workflow execution, allowing NeWT to effectively manage and recover from workflow changes at any time. We evaluate NeWT by comparing the same example across multiple commercial systems that claim reconfiguration capabilities.

Programming Language Design for Event-Driven Service Composition

To adapt to rapidly changing market conditions and increase the return of investment, today's IT solutions usually combine service-oriented architecture (SOA) and event-driven architecture (EDA) that support reusability, flexibility, and responsiveness of business processes. Programming languages for development of event-driven service compositions face several main challenges. First, a language should be based on standard service composition languages to be compatible with SOA-enabling technologies. Second, a language should enable seamless integration of services into event-driven workflows. Third, to overcome a knowledge divide, language should enable seamless cooperation between application developers with different skills and knowledge.Since WS-BPEL is widely accepted as standard executable language in SOA, we extended WS-BPEL with support for event-driven workflow coordination. We designed event-handling mechanisms as special-purpose Coopetition services and augmented WS-BPEL with primitives for their invocation. Coopetition services augment SOA with fundamental EDA characteristics: decoupled interactions, many-to-many communication, publish/subscribe messaging, event triggering, and asynchronous operations. To make the application development familiar to wide community of developers, we designed an application-level end-user language on top of WS-BPEL whose primitives for invocation of regular Web services and Coopetition services resemble the constructs of typical scripting and coordination language.

An efficient asynchronous mobile web service framework

The popularity of web services within the IT industry continuous to grow. Accessing web services from a small device is very com-mon these days. There are number of challenges to access a web services on mobile device due to its limited resources and the lack of bandwidth in its communication network. In Mobile devices, Synchronous web services are not feasible. It makes the user wait while each Web service processes requests and returns results. Asynchronous Web services invocation solves this performance issue and enhances the end user experience by increasing server efficiency. The architecture of asynchronous web services is con-trollable and monitor able. In order to enhance the efficiency of a mobile web services, we have created a bridge between telephony application and web application. We integrate the telecommunica-tion facility and asynchronous invocation of web services. It ex-poses telephony services as web services, so that web application can easily access telecommunication facilities through SMS messaging.

A hierarchical framework for logical composition of web services

Automatically composing Web services to form processes in the context of service-oriented architectures has attracted significant research. Prevalent approaches for automatically composing Web services predominantly utilize planning techniques to achieve the composition. However, classical planning based approaches face the following challenges: (i) difficulty in modeling the uncertainty of Web service invocations, (ii) inability to optimize the composition using non-functional parameters, and (iii) difficulty in scaling efficiently to large compositions. In order to address these issues, we present a hierarchical framework for logically composing Web services, which we call Haley. In comparison to classical planners, Haley utilizes decision-theoretic planning that is able to model and reason with the uncertainty inherent in Web service invocations and provides an expected cost-based optimization. Haley uses symbolic planning techniques that operate directly on first-order logic based representations of the state space to obtain the compositions. Consequently, it supports automated elicitation of the corresponding planning problem from Web service descriptions and produces a domain representation that is more compact than that of classical planners. Furthermore, it promotes scalability by exploiting the natural hierarchy found in real-world processes. Due to the limitations of the existing approaches and the complexity of the Web service composition problem, few implemented tools exist, although many approaches have been proposed in the literature. We have implemented Haley and provided a comprehensive tool suite for composing Web services. The suite operates on Web services described using well-known languages such as SAWSDL. It provides process designers with an intuitive interface to specify composition requirements, goals and a hierarchical decomposition if available, and automatically generates BPEL compositions while hiding the complexity of the planning and of BPEL from users.