Web Service Composition Framework Research Articles

Research on Dynamic Web Services Composition Framework Based on Quality of Service

Research on Dynamic Web Services Composition Framework Based on Quality of Service

Quality-of-Service Based Web Service Composition and Execution Framework

Software is gradually becoming more built by composing web services to support enterprise applications integration; thus, making the process of composing web services a significant topic. The Quality of Service (QoS) in web service composition plays a crucial role. As such, it is important to guarantee, monitor, and enforce QoS and ability to handle failures during execution. Therefore, an urgent need exists for a dynamic Web Service Composition and Execution (WSCE) framework based on QoS constraints. A WSCE broker is designed to maintain the following function: intelligent web service selection decisions based on local QoS for individual web service or global QoS based selection for composed web services, execution tracking, and adaptation. A QoS certifier controlled by the UDDI registry is proposed to verify the claimed QoS attributes. The authors evaluate the composition plan along with performance time analysis.

Human-Computer Collaborative Service Composition for Service-Oriented Manufacturing Integrated Systems

In view of the characteristics and difficulties of service composition, taking particularities of enterprise product design and manufacture into consideration, in order to improve the efficiency of service composition for manufacturing integrated systems, a collaborative semantic web service composition framework based on abstract business process was proposed to construct the workflow by way of man-computer collaboration, and the key technologies involved in this framework such as service modeling, searching, binding and execution were analyzed in detail.

A monolithic approach to automated composition of semantic web services with the Event Calculus

In this paper, a web service composition and execution framework is presented for semantically -annotated web services. A monolithic approach to automated web service composition and execution problem is chosen, which provides some benefits by separating composition and execution phases. An AI planning method using a logical formalism, namely Abductive Event Calculus, is chosen for the composition phase. This formalism allows one to generate a narrative of actions and temporal orderings using abductive planning techniques given a goal. The functional properties of services, namely input/output/precondition/effects (IOPE) are taken into consideration in the composition phase and non-functional properties, namely Quality of Service (QoS) parameters are used in selecting the most appropriate solution to be executed. The repository of OWL-S semantic web services are translated to the Event Calculus axioms and the resulting plans found by the Abductive Event Calculus Planner are converted to graphs. These graphs can be sorted according to a score calculated using the defined quality of service parameters of the atomic services in the composition to determine the optimal solution. The selected graph is converted to an OWL-S file which is executed consequently.

Testing Conformance of BPEL Business Process Based on Model Checking

Formalized analysis method is a technology that insures quality of software reliability. It can detect mistakes and flaws effectively in software design. Based on the research of model checking techniques for composition of web services, we establish an automatic test framework for web services composition of BPEL. Static test method is used and test cases are generated automatically in this framework. According to the input, outputs of cases and the requirement properties, we can test the conformance for business flow of BPEL. We analyze “Airline Tickets Reservation System” which is described by BPEL with our test framework and test the conformance of the system. In addition, we compare our method to model checking method which is used to verify web services composition from three areas including states stored, searching depth and consuming times. We can conclude that our method have a better efficiency when checking the web services which owns more states.

AdaFF: Adaptive Failure-Handling Framework for Composite Web Services

In this paper, we propose a novel Web service composition framework which dynamically accommodates various failure recovery requirements. In the proposed framework called Adaptive Failure-handling Framework (AdaFF), failure-handling submodules are prepared during the design of a composite service, and some of them are systematically selected and automatically combined with the composite Web service at service instantiation in accordance with the requirement of individual users. In contrast, existing frameworks cannot adapt the failure-handling behaviors to user's requirements. AdaFF rapidly delivers a composite service supporting the requirement-matched failure handling without manual development, and contributes to a flexible composite Web service design in that service architects never care about failure handling or variable requirements of users. For proof of concept, we implement a prototype system of the AdaFF, which automatically generates a composite service instance with Web Services Business Process Execution Language (WS-BPEL) according to the users' requirement specified in XML format and executes the generated instance on the ActiveBPEL engine.

Semantic Web service composition framework based on abstract template

template was proposed,and analysis of the template retrieval,data pre-processing and template adaptation modules of this framework were introduced in detail. In order to improve the accuracy of the template retrieval,the framework adopted the feature matching and graph matching methods in the similarity computation between the abstract template and the user's request. Besides,it constructed the service dependency graph through the data pre-processing,deleted the useless services and verified the satisfiability of the user's request. According to the service dependency graph,it implemented the automatic template adaptation,by using the Heuristic Plan Adaptation Algorithm (HPAA),and improved the adaptability and scalability of HPAA by providing the function of the flexible configuration of the heuristic strategies. Finally,the experiments on the different heuristic strategies show the effectiveness and reliability of HPAA when dealing with the large-scale problems.

SWSCF: A Semantic-based Web Service Composition Framework

Web service composition is gaining a considerable momentum as an approach to the effective integration of distributed, heterogeneous, and autonomous application. Current composed service processes are mostly generated in the syntactic level and in a manual way. The limitation of the approach is that it does not allow business to dynamic change partners and services. In order to avoid this disadvantage, it is critical to map complex business from abstract process to executable flows according to application domain semantics and dynamic business requirements. In this paper, we first present a semantic-based Web service composition framework called SWSCF based on both semantic process recommendation and semantic matchmaking. Then, we analyze some key technologies including: (1) Introducing hierarchical activity mechanism for dynamic decomposition of business requirements to find a suitable semantic process template; (2) Searching and selecting service chain to match a semantic activity template which is used to specify an abstract activity; (3) Devising heterogeneous message transforming mechanism to eliminate the incompatible message types during generating data flow of an executable process. Furthermore, by comparison with some service composition frameworks, we prove SWSCF to be more flexible and effective.

Dynamic web service composition based on OWL-S

Composing existing web services for enterprise applications may enable higher level of reuse. However the composition processes are mostly static and lack of support for runtime redesign. In this paper, we describe our approach to the extension of the OWL-S ontology framework for dynamic web service composition. We raise the level of abstraction and propose an abstract service layer so that web services can be composed at the abstract service level instead of the concrete level. Each abstract service is attached with an instance pool including all instances of the abstract service to facilitate fail-over and dynamic compositions.

Context-based matching for Web service composition

In this paper, we propose a novel matching framework for Web service composition. The framework combines the concepts of Web service, context, and ontology. We adopt a broad definition of context for Web services, encompassing all information needed for enabling interactions between clients and providers. Context-based matching for Web services requires dealing with three major research thrusts: context categorization, modeling, and matching. We first propose an ontology-based categorization of contextual information in Web service environments. We then define a two-level mechanism for modeling Web service contexts. In the first level, service providers create context specifications using category-specific Web service languages and standards. In the second level, context specifications are enveloped by policies (called context policies) using WS-Policy standard. Finally, we present a peer-to-peer architecture for matching context policies. The architecture relies on a context matching engine, context policy assistants, and context community services. Community services implement rule-based techniques for comparing context policies.

A Service-Oriented Composition Framework with QoS Management

Quality of Services (QoS) management in compositions of services requires careful consideration of QoS characteristics of the services and effective QoS management in their execution. This paper describes an approach to implementation of QoS management in compositions of Web services in the context of Computational Quality Attributes and Service Level Agreements. Building on prior research work of others in the use of Message Detail Records, this paper integrates the results from several research threads to propose a QoS Management Architecture to support dynamic processing of service- and flow level quality attributes to support QoS requests and analyses in Web-service-oriented architectures. The study of QoS management in a Web service composition framework was motivated by the evolution of the composition framework for a toolkit for integration and experimentation of distributed system applications. A message tracking model is proposed for supporting QoS end-to-end management by applying the Computational Quality Attribute (CQA) concepts of Flow-Service-Quality engineering. Quality attributes are defined, computed and acted upon as dynamic characteristics of systems, with values constantly changing in operation. A CQA provision is illustrated, with a simple Web Services travel reservation example. The example is elaborated to illustrate QoS end-to-end management using the Simple Object Access Protocol (SOAP) message tracking model.

Ontology-Supported Web Service Composition

Web service composition can enhance the efficiency and agility of knowledge management by composing individual Web services together for complex business requirements. There are two main research streams in knowledge representation for Web service composition: the syntactic-based approach and the semantic-based approach. Despite the promises brought by each approach, the two streams are largely separated from each other. In this article, we propose an integrated ontology-supported Web service composition framework, which provides a novel solution to organizational knowledge management. By synergistically leveraging both syntactic-based and semantic-based approaches, this framework provides dual modes to perform service composition. Ontologies are employed to enrich semantics at both the service description and composition levels. The proposed conceptual framework has been implemented in the corporate financial services domain. It is demonstrated that the shared ontology helps to fulfill automated and on-the-fly service composition in particular and knowledge management in general.

Towards a Framework for Agent-Enabled Semantic Web Service Composition

The article presents the framework for agent-enabled dynamic Web service composition. The core of the methodology is the new understanding of a Web service as an agent capability having proper ontological description. It is demonstrated how diverse Web services may be composed and mediated by dynamic coalitions of software agents collaboratively performing tasks for service requestors. Middle Agent Layer is introduced to conduct service request to task transformation, agent-enabled cooperative task decomposition and performance. Discussed are the formal means to arrange agents’ negotiation, to represent the semantic structure of the task-activity-service hierarchy and to assess fellow-agents’ capabilities and credibility factors. Finally, it is argued that the presented formal technique is applicable to various application domains. Presented is the ongoing work on designing and implementing agent-based layered architecture for intelligent rational information and document retrieval. Finally, the discussion of the OntoServ.Net framework for the development of P2P mobile service infrastructures for industrial asset management provides the extension of the Web service composition approach.