An Approach to Composing Web Services with Context Heterogeneity

The automatic composition of Web Services has been explored in the literature from different standpoints. It aims to create an execution plan for the flow of Web Services based on requests made and sent by the client, by following the stages necessary for the generation of composite services and then carrying out the execution of the workflow that has been designed. However, no research studies have been found that undertake the whole process of an automatic composition and execution, from the user's request to the execution of the services chosen as a solution. Therefore, the goal of this paper is to evaluate the performance of an automatic Web Service composition, since the request made by the client, to the delivery of the results of the executed composition. This article examines the integration between two tools, the automatic web service composition system and the extensible platform to evaluate semantic web services with the aim of conducting a performance evaluation of an entire process of automatic composition of Web services.

The automatic composition of Web services requires the existing services to be encoded in a semantic form, such as ontology. If Web services are represented with ontology, we can automatic compose Web services by means of their semantics. Ontology modeling is divided into two steps: input/output parameters modeling and Web services modeling. First, we collect Web services' input/output parameters, represent them with classes in ontology, and transform Web services to properties in ontology, define relations between classes and properties. Then we judge Web services' relations based on relations between properties transformed from these Web services and estimate whether these Web services can be composed.

Through providing an execution environment for semantic web services, SWSF (Semantic Web Service Framework) can facilitate automatic web service delivery, discovery, selection, invoking, composition and interoperation. However, each of those ongoing approaches does not satisfy all basic requirements of SWSF, e.g. OWL-S (Ontology Language of Web Service) does not offer the mechanism for automatic web service tasks' execution and WSMO can not describe the composition of web services in a structural way yet. So, in order to provide a fully- fledged SWSF, we present the ISCF (Integrated Service Composition Framework) which is based on the OAA (Open Agent Architecture ). We describe the technical characters and design objectives of ISCF from global and detailed view. Comparing with other SWSFs, ISCF has more extensible and autonomous distributed architecture, and has more complete and effective web service automatization. In addition, ISCF provide some useful tools to help users design semantic web services and manage ISCF system.

Web services play an important role in the development of distributed systems. Particularly, the possibility of composing already implemented web services in order to provide new functionalities is an interesting approach for building distributed applications and business processes. In this paper we focus on mismatches occurring during dynamic composition of web services. We propose an algorithm for dynamic and automatic composition and adaptation of web services. Our approach only uses the information that is already available in service interface descriptions. The algorithm allows programmers to define dynamic web service compositions without changing the source code.

The automatic composition of semantic Web services is one of challenging areas of semantic Web services research. Mathematical semantic Web services are very useful in practice, however only a small number of related research results are reported. In this paper, we will show a dynamic, automated composition method for mathematical semantic Web services, using intelligent agents. The paper is focused on solving a kind of mathematical puzzle, called the countdown problem. In addition, we will show a static, manual composition method for Web services.

Automatic web service composition is defined as the const ruction of virtual enterprises as complex services on demand. In the current research scenario choosing business service partners for composition on the fly is usually determined with user-centric metrics and deficient of provider’s business specific metrics. Automatic web service composition in today’s real world business circumstances is more of a toy model due to the lack of service provider collaboration metrics [1]. SLAKY System is a new model for selection of business service partners by adding servic e provider metrics to user centric metrics enabling strategic and realistic selection of services for composition. SLAKY System selects services automatically considering the vision, time planning, environmental context, user adoption, usage policies, trus t management, risk management, market scenario, native intelligence, and competitive profit management as service provider collaboration metrics in addition to functionality satisfaction metrics for client’s requirements. The time planning metric was designed using opus deviser algorithm [2] and profit management using SLAKY BWG algorithm [3]. In this paper we focus on strategic selection of semantic services based on the metric of native intelligence. Howard Gardner, psychology professor, Harvard Universit y, defines intelligence as an ability to solve problems, or to create products, that are valued within one or more cultural settings. Richard Heck, Professor of Natural Theology, Brown University, in his work states that native intelligence is primarily influenced by racial and cultural differences. User preferences in any sector intend to have native influence. For example the affinity towards entertainment services for Indian Premier League or low cost car booking service for TATA Nano is more in India th an America. Moreover decision made by a decision maker is motivated by native intelligence in addition to Intelligence Quotient and is valued highly in native grounds. For example the selection of a matrimonial service totally relies on native aspects. Native Intelligence is also a significant metric to improve time -to-market and quality in the launch of any product. Considering the significance of native intelligence in strategic selection we layer native intelligence descriptions for realistic selection o f semantic web services on the fly. OWL -S upper ontology that describes semantics of services for automation of service discovery, selection, composition, orchestration and invocation lacks entities for semantic modeling of native intelligence. In this pap er we propose an extended OWL -S ontology which augments where, why and who native status descriptions of a service apart from the existing what (ServiceProfile sub -ontology) and how (ServiceModel, ServiceGrounding sub-ontology) semantics. The why, whereand who semantics are newly augmented as ServiceParameters of Profile sub -ontology using sParameter property. We also propose Naavi algorithm that reasons with common sense knowledge for selection of the web service that is highly valuable in a native context using native description in extended OWL -S.

In a domain SOA environment, multiple services exist to help in executing the users requests but manually handling each request is time wasting and very tiring thus the idea of automatic composition of web services emerged. This paper describes the ACUAI framework which is an AI automatic composer for web services with learning capabilities, since games have the most developed dynamic system adaptation to user action this framework uses two AI techniques which are used in games development they are decision trees and the finite state machines, the user request will be handled in the same way games react to user input then a decision is taken based on current state of the orchestration and then the algorithm changes the state of the orchestration according to the last decision taken to be able to guide the orchestration towards the goal and get a successful composition then each successful composition and its template request are saved to be used later on in enhancing the execution time.

The growth of Web service formats over the Internet is increasing. These services should often be composed to achieve a user request. We propose in this paper a framework to cope with web service composition, from discovery to optimization. This framework, called SPOC, is composed of four successive phases: discovery, planning, quote execution and optimization. Only RFQ (Request for Quote) web services are treated in this first version of SPOC. The Discovery phase aims to search for web services in a repository. The Planning phase determines which services satisfy the user request. The Quote Execution phase involves processing a Request For Quote (RFQ) by calling web services. The last phase optimizes these results giving tradeoff compositions. As a proof-of-concept example, we applied SPOC to public competition processes in Public Markets.

With the proliferation of Web services and the evolution towards the Semantic Web comes the opportunity to automate various Web services tasks. A number of approaches have been proposed to tackle the problem of automatic web service composition. Most of them are inspired by the researches in AI planning. As heuristics plays a key role in the promotion of planning efficiency, the selection of heuristic mechanism is very important. In this paper, we propose the conception of composition distance, and propose a heuristic bidirectional search algorithm based on composition distance. The most contribution of this paper is : (1)propose the conception of composition distance; (2)a heuristic bidirectional search algorithm. The algorithm we proposed is effective and efficiency when applied in web service composition engine.

A difficulty of sharing messages transferred among Web services is absence of common vocabulary, and the semantic organization and description of Web services is an important requirement for enabling the automatic discovery, selection, composition, execution and monitoring of Web services. This paper proposes a model for semantic-based interaction between Web services. The method defined some ontology-based vocabularies to describe different Web services and some mapping rules among those vocabularies. Compared with existing methods, the method considers the Web services together with the semantic interpretation, satisfiability and reasoning of distributed ontologies. So the method can ensure the share and reusage of term be used for describing parameters of Web services.

Managing Service Level Agreement (SLA) for composite semantic web services is a very complex process, as it involves many complex tasks such as components discovery, provisioning, monitoring, recovery, and coordination. Indeed, managing all these tasks manually is a very cumbersome operation, nevertheless it is time consuming and prone to errors. To overcome such problems, automated SLA management for composite semantic web services is needed. This requires the SLA of the composite service to be described in a machine-understandable format such that it can be understood and processed by the automated SLA management tool. Currently, there is no SLA description language for composite semantic web services, but there exists an SLA description language for atomic web services, known as the Web Service Level Agreement (WSLA). Hence, in this paper, we aim to extend the WSLA language to describe composite semantic web services' SLAs, then we show how we can automatically generate the components' SLAs from the composite semantic web services' SLAs; adopting the CRECENT framework that we previously proposed for managing composite web services.

With the growth of web service in quantity, it has become an urgent issue how to compose web service with effective method so as to capacitate web service providers to work cooperatively and exert greater function. The paper introduces web service composition method based on rules and meta-services. Meta services are the abstraction of web services with similar functions, while rules are used to describe logic relation and data dependence relation among meta-services. An algorithm that generates the abstract service composition process based on the rules and meta-services is designed. The abstract service composition process is converted into executable process by employing web service discovery. The method proposed in this paper is proved to be feasible by the application in travel platform.

Automated composition of Web services has received much interest in the last decade, as it supports B2B applications. It aims at selecting and inter-connecting services provided by different partners in response to client requests. Planning techniques are used widely in the literature to describe Web services composition problem. However, since Web services proliferate day after day, classical planners are no longer well suited to compose Web services in a reasonable time. This weakness is due to the explosion of the search space caused by the large number of services and the broad range of data exchanged among services. In this paper, we propose a decentralised multi-agent approach to solve the Web services composition problem at runtime. Our model consists of a set of Web service agents where each agent has a set of services organised in a graph. Responding to a request, agents propose partial plans which are partial paths in the graph, then they coordinate their partial plans to provide the best global plan for the submitted request. The analysis of the complexity and results of the implementation show the ability of our approach to scale up when compared to the of state-of-the-art techniques for automated web service composition.

최근에 동적으로, 즉 요구가 있는 즉시 서비스들을 조합하는 동적 웹 서비스 조합은 가장 큰 관심사 중 하나이다. 지금까지 동적 웹 서비스조합에 관한 많은 연구들이 수행되어졌는데 주로 사람이 개입된 반자동 대화식 조합 기법들이 제안되었다. 또한 이들 연구에서 탐색 알고리즘 및 워크플로우 설계 기법들이 부분적으로는 기술되어 있으나. 웹 서비스 조합 자동화를 위한 전반적인 워크플로우 처리과정을 기술한 연구는 아직 없다. 본 논문은 웹 서비스 조합 자동화 기법에 초점을 맞추고 있다. 주된 아이디어는 시멘틱 웹을 실현하기 위한 웹 온톨로지와 비즈니스분야에서 성공적으로 활용되고 있는 워크플로우 기법들을 적용하여 웹 서비스 조합 자동화 시스템을 구현하는 것이다. 본 연구에서는 웹 서비스발견을 위해 매칭 알고리즘이 제안되고, 웹 서비스들 간 상호연결을 지원하기 위해 매칭 알고리즘에 온톨로지 개념이 적용된다. 그리고 웹 서비스 조합 자동화를 지원하기 위한 워크플로우 실행계획이 기술된다. 마지막으로 실 데이터 실험을 통해 제안 시스템의 우수성을 보인다. Recently, one of the most challenging problems is to compose web services dynamically, that is, on demand. A number of researchers have been considerably interested in the dynamic web services composition. However, while most of them focused on the semi-automatic web services composition with a human controller, very little attention was devoted to the full automation of this process. This paper primarily focuses on the automatic web services composition techniques. The main idea is to implement an automatic web services composition system using web ontologies to realize the semantic web and workflow technologies to play a major role in E-businesses. In this paper, we propose a matching algorithm for web service discovery and present an approach based on the use of ontologies to facilitate the interoperability of web services. Finally, we describe a workflow execution plan to support the automatic web services composition, and an experimental study that shows the high performance of our system.

Automatic composition of Web services requires that the providers publish an abstract version of their Web services to a registry. They offer this abstraction instead of the complete web service to ensure the privacy of their internal know-how and trade secrets. Many studies have offered methods to do this, but none of them is able to formally prove their ability to keep the secret information hidden. In this article we turn to the verification of opacity, a formal security property that allows not only to preserve the secret but also to formally prove that it remains hidden. In particular, we investigate if the composition of two opaque Web services is also opaque. Our work consists in verifying the opacity of the composition of two Web services through the verification of the opacity of their individual abstractions represented by Symbolic Observation Graphs.