Automatic Web Service Composition Research Articles

Transactional Automaton-driven Web Services Selection

“ Transactional Automaton-driven Web Services Selection ” by Weitao Ha Journal of Computers Volume 8, Number 2, February 2013, Page(s): 290-293 After careful and considered review of the content and authorship of this paper by a duly constituted expert committee, the above paper has been found to be in violation of Academy Publisher’s Publication Principles. This paper contains significant portions of original text from the papers cited below. The original text was copied without attribution (including appropriate references to the original authors and/or paper title) and without permission: Due to the nature of this violation, reasonable effort should be made to remove all past references to this paper, and future references should be made to the following articles: [1] Joyce El Haddad, Maude Manouvrier, Marta Rukoz: TQoS: Transactional and QoS-Aware Selection Algorithm for Automatic Web Service Composition. IEEE T. Services Computing 3(1): 73-85 (2010) [2] Joyce El Haddad, Maude Manouvrier, Guillermo Ramirez, Marta Rukoz: QoS-Driven Selection of Web Services for Transactional Composition. ICWS 2008: 653-660

Modeling Native Intelligence Semantics for Indigenous Selection of Web Services Using Slaky Composer

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.

A Study on Composition Goal in Automated Web Services Composition Approaches

Web Services Composition (AWSC) has received more attention in the research community. In the literature, automated composition of web services problem has been identified to find approaches that realize a particular request by detecting, composing and executing web services automatically. Goal-driven Architecture provides a promising solution to this problem. It allows a composition system to formulate a request in terms of a goal and solves it by automatically discovering, composing and executing appropriate web services. The main element of this architecture is the concept of goal because a goal carries all the necessary information for automated discovery, composition and execution of web services. Our aim is to study the Automated Web services composition approaches based on this architecture and to analyze them based on the concept of goal.

An Optimal and Complete Algorithm for Automatic Web Service Composition

The ability of web services to build and integrate loosely-coupled systems has attracted a great deal of attention from researchers in the field of the automatic web service composition. The combination of different web services to build complex systems can be carried out using different control structures to coordinate the execution flow and, therefore, finding the optimal combination of web services represents a non-trivial search effort. Furthermore, the time restrictions together with the growing number of available services complicate further the composition problem. In this paper the authors present an optimal and complete algorithm which finds all valid compositions from the point of view of the semantic input-output message structure matching. Given a request, a service dependency graph which represents a suboptimal solution is dynamically generated. Then, the solution is improved using a backward heuristic search based on the A* algorithm which finds all the possible solutions with different number of services and runpath. Moreover, in order to improve the scalability of our approach, a set of dynamic optimization techniques have been included. The proposal has been validated using eight different repositories from the Web Service Challenge 2008, obtaining all optimal solutions with minimal overhead.

A distributed multi-agent planning approach for automated web services composition

The ability to automatically answer a request that requires the composition of a set 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. Therefore it is more interesting to use a decentralized planner to distribute the search space and the computing load taking into account the distributed nature of the problem. In this paper, we propose a distributed multi-agent approach to solving the web services composition problem at runtime. Our approach consists of a set of web services agents where each agent has a set of services organised in a graph. To respond to a request, agents propose their best local partial plans which are partial paths in the graph. They then coordinate their partial plans to provide the best global plan for the submitted request. The analysis of the complexity and the results of the implementation show the ability of our approach to scaling up when compared to the state-of-the-art techniques for automated web services composition.

A Distributed Algorithm for Web Service Composition Based on Service Agent Model

Agent-based service composition has provided a promising computing paradigm for the automatic web service composition. In this paper, a formal service agent model is proposed, which integrates the web service and software agent technologies into one cohesive entity. Based on the service agent model, a distributed planning algorithm for web service composition called DPAWSC is presented. DPAWSC formalizes web service composition into a graph search problem according to the dependence relations among service agents. The key to DPAWSC is that the alternative solution with smaller length has higher priority to be searched than one with larger length. DPAWSC is based on the distributed decision making of the autonomous service agents and addresses the distributed nature of web service composition. We evaluate the algorithm by simulation experiments and the results demonstrate that DPAWSC is effective for its ability to produce the high quality solution at a low cost of communications.

Research on Context-aware Web Service Composition based on the Fluent Calculus

With the exponential growth in available web services and diversity of user needs, automatic web service selection and composition techniques have attracted the attention of many researchers. This paper presents a fluent calculus-based, context-aware web service composition model. The model uses an artificial intelligence (AI) planning-based web service composition technique, which translates web service composition problems into AI planning problems, and then achieves target goals by acquisition and reasoning using existing environmental knowledge. We first construct a model for service, service context, and service composition on the basis of the fluent calculus theory. Then, we extend the basic axioms of the fluent calculus (initial state and state update axioms) to describe context information, an approach that endows context-aware ability to the fluent calculus-based web service composition. Furthermore, we implement a fluent calculus-based, context-aware web service composition model using a fluent calculus executor or FLUX in a digital tourism service scenario. The experimental results show that the proposed model has context-aware capability and exhibits better performance in service composition.

Automatic composition of information-providing web services based on query rewriting

Compared with normal web services, information-providing services have unique features that have seldom been considered in existing research on the automatic composition of web services. In this paper, we present a simple, yet well-formed, semantic-based capability model for information-providing web services, which can express such features as not modifying the world state and not requiring all input/output parameters to be supplemented with class information as semantics. We then present a corresponding automatic composition method derived from a query rewriting algorithm, MiniCon, used in the data integration field. This method adequately utilizes previous features, enables primitive semantic reasoning, and can generate executable BPEL scripts automatically. Performance of the method is complementary to traditional search-based ones. Experiments on a typical type of problem show that the method is usable in practice.

Automatic Web services composition algorithm based on optimal matching

A novel layered method was proposed to solve the problem of Web services composition. In this method, services composition problem was formally transformed into the optimal matching problem of every layer, then optimal matching problem was modeled based on the hypergraph theory, and solved by computing the minimal transversals of the hypergraph. Meanwhile, two optimization algorithms were designed to discard some useless states at the intermediary steps of the composition algorithm. The effectiveness of the composition method was tested by a set of experiments, in addition, an example regarding the travel services composition was also given. The experimental results show that this method not only can automatically generate composition tree whose leaf nodes correspond to services composition solutions, but also has better performance on execution time and solution quality by adopting two proposed optimization algorithms.

信息提供类Web 服务基于查询重写的自动组合方法

Compared with normal web services, information-providing services have unique features that have seldom been considered in existing research on the automatic composition of web services. In this paper, we present a simple, yet well-formed, semantic-based capability model for information-providing web services, which can express such features as not modifying the world state and not requiring all input/output parameters to be supplemented with class information as semantics. We then present a corresponding automatic composition method derived from a query rewriting algorithm, MiniCon, used in the data integration field. This method adequately utilizes previous features, enables primitive semantic reasoning, and can generate executable BPEL scripts automatically. Performance of the method is complementary to traditional search-based ones. Experiments on a typical type of problem show that the method is usable in practice.

Automated web service composition supporting conditional branch structures

The creation of value-added services by automatic composition of existing ones is gaining a significant momentum as the potential silver bullet in service-oriented architecture. However, service composition faces two aspects of difficulties. First, users' needs present such characteristics as diversity, uncertainty and personalisation; second, the existing services run in a real-world environment that is highly complex and dynamically changing. These difficulties may cause the emergence of nondeterministic choices in the process of service composition, which has gone beyond what the existing automated service composition techniques can handle. According to most of the existing methods, the process model of composite service includes sequence constructs only. This article presents a method to introduce conditional branch structures into the process model of composite service when needed, in order to satisfy users' diverse and personalised needs and adapt to the dynamic changes of real-world environment. UML activity diagrams are used to represent dependencies in composite service. Two types of user preferences are considered in this article, which have been ignored by the previous work and a simple programming language style expression is adopted to describe them. Two different algorithms are presented to deal with different situations. A real-life case is provided to illustrate the proposed concepts and methods.

Web Service Composition Algorithm

Web service composition is very important in web service technology. Domain Ontology is used for semantic web service match and automatic web service composition. When a web service is registered, it will be related to the concepts in the domain ontology with its output concepts. To start a semantic match or composition starts, only the related web service with the annotated concept will be used. The approach can deal with not only the sequential but also the parallel service composition problems The proposed approach was verified by experiments and case studies.

Automatic Web service composition based on Horn clauses and Petri nets

This paper introduces an automatic Web service composition method based on logical inference of Horn clauses and Petri nets. The Web service composition problem is transformed into the logical inference problem of Horn clauses by exploring the dependency relations among services. An algorithm is presented, to determine whether the composite service exists in time that is linear in the size of the knowledge base. It can also return the rule set necessary for the composition. Petri nets are chosen to model the rule set and its structural analysis techniques are used to obtain the composite service.

Directed level graph-based approach to automatic Web services composition

To solve the problem of automatic Web services composition with multiple inputs/outputs,an approach based on directed level graph was proposed.It provided an optimal composition sequence through these steps as follows:1) Built a directed level graph by inputs/outputs of user request;2) Built a complete reduction graph of the directed level graph;3) Searched all reachable paths for every node of complete reduction graph;4) Converted the optimal path for user request into services composition sequence.This approach can generate all composition sequences with least steps and an optimal composition sequence according to the quality of services.Compared with traditional graph-based approach,it reduces search space and avoids cycle searching and can be applied in a large scale of Web services repository.

Using Markov Decision Process Model with Logic Scoring of Preference Model to Optimize HTN Web Services Composition

Automatic Web services composition can be achieved using AI planning techniques. HTN planning has been adopted to handle the OWL-S Web service composition problem. However, existing composition methods based on HTN planning have not considered the choice of decompositions available to a problem, which can lead to a variety of valid solutions. In this paper, the authors propose a model of combining a Markov decision process model and HTN planning to address Web services composition. In the model, HTN planning is enhanced to decompose a task in multiple ways and find more than one plan, taking into account both functional and non-functional properties. Furthermore, an evaluation method to choose the optimal plan and experimental results illustrate that the proposed approach works effectively. The paper extends previous work by refining a number of aspects of the approach and applying it to a realistic case study.

A New Model for Web Service Composition

To support automated Web service composition, it is compelling to provide a template, or model that dictates the ways in which services can be composed. In this paper, a novel composition model based on the relative vector is proposed, where individual services, composite services, and user objectives are described with the relative vectors, through a series of operators defined on the relative vector, available composite services can be found, and how much they meet user objectives can be evaluated. A significant advantage of our approach is that many existing optimization methods can be used to search optimized compositions, where parallel or choice structure is enabled, individual service with multiple input or output parameters is allowed.

PlanICS - a Web Service Composition Toolset

The paper presents a prototype toolset to planning by automatic composition of web services. The main idea consists in arranging the composition into two main phases: abstract and concrete one, as well as to handle fully declarative user queries. The first abstract stage aims at finding all the possible sequences of the types of the services that can potentially satisfy the user request. The result, referred to as an abstract plan, is used in the concrete planning phase, which substitutes the types of the services with their concrete instances registered in the system. This is obtained by translating the problem of finding a composition of concrete services satisfying the user query into the reachability problem for (timed) automata with discrete data and parametric assignments, taking into account the concrete instances of services as well as the user query. Next, SAT-based parametric bounded model checking is used to obtaining the solutions in form of sequences of services invocations together with the example services' input values.

Dynamic planning approach to automated web service composition

In this paper, novel ideas are presented for solving the automated web service composition problem. Some of the possible real world problems such as partial observability of the environment, nondeterministic effects of web services and service execution failures are solved through a dynamic planning approach. The proposed approach is based on a novel AI planner that is designed for working in highly dynamic environments under time constraints, namely Simplanner. World altering service calls are done according to the WS-Coordination and WS-Business Activity web service transaction specifications in order to physically recover from failure situations and prevent the undesired side effects of the aborted web service composition efforts.

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.

Utilizing the interactive techniques to achieve automated service composition for Web Services

Web Service (WS) is used to support implementation of the distributed system and has already achieved interoperability with a variety of online platforms. This result is accomplished by loosely coupling many different services together. However, as the Internet environment becomes more and more complex, this objective also becomes more difficult to fulfill. For the purpose of maintaining correctness and automated WS composition, effectively managing the WSs and inter-WS interaction in the WS environment will be a major challenge for future infrastructure. In this paper, we propose a distributed infrastructure utilizing interactive techniques to achieve automated WS composition.