Service Composition Application Research Articles

Norm-based reinforcement learning for QoS-driven service composition

QoS-aware service composition is challenging due to a high number of QoS attributes, component services, and candidate services. Realistic service composition applications operate in uncertain environments where QoS values may change dynamically. Moreover, user requirements on QoS attributes should be considered, and their different nature can make it difficult to express them by adopting relative weights. Reinforcement Learning is proposed as a viable approach in order to deal with the complexity and variability of the environment. In this paper, we propose a novel approach that integrates traditional reinforcement learning with a norm-based paradigm to consider cases where component services may have a different number and types of QoS attributes. In such a way, it is possible to consider additional local requirements that may hold only for specific service components still pursuing a global optimization. Norms allow using a uniform formalism to express qualitative and quantitative as well as hard and soft user requirements. The approach has been tested on a real dataset of 2500 web services showing its performance, scalability, and adaptability properties.

An Efficient IIoT Gateway for Cloud–Edge Collaboration in Cloud Manufacturing

The cloud manufacturing system can provide consumers with on-demand manufacturing services, which significantly improve the utilization rate of distributed manufacturing resources and the response speed of personalized product needs. In the cloud manufacturing platform, the successful implementation of various industrial applications relies on the uploading and streaming of related field-level manufacturing data. For example, the realization of manufacturing service composition application should match the manufacturing tasks with distributed manufacturing resources according to their working state data and performance measurement data. Therefore, this paper proposes a data integration and analysis framework of a cloud manufacturing system based on cloud–edge collaboration and the Industrial Internet of Things (IIoT). A service-oriented information model is established to uniformly describe the related operational data and functional attributes of heterogeneous manufacturing resources. Secondly, a real-time transmission and integration method of high-volume operational field and sensor data based on message middleware is proposed to realize the remote monitoring of distributed manufacturing resources and efficient distribution of related data. Finally, a cloud–edge collaboration mechanism is put forward to train and update the parameters of various artificial intelligence models deployed at edge gateways. In the experiment, taking the computer numerical control (CNC) lathe as an example, the effectiveness of the proposed manufacturing resource access method is verified. Taking the fault diagnosis model of the CNC lathe as an example, the efficiency of the proposed cloud–edge collaboration mechanism for model updating is verified.

IWSN: A novel method for modeling the interaction of web services

As the most notable implementation of service-oriented architectures, web services has brought some challenging research issues, one of which is the composition. Correct interaction among web services is the prerequisite of their successful composition. In this paper, we propose a novel approach to model dynamic interactive behavior of web services, aiming to effectively take advantage of the flexibility of service composition technology and guarantee the behavior compatibility of web services and further to facilitate the application of web service composition in healthcare field. An interaction model of web services based on Kahn process network (KPN) is presented in this paper, which is a data-flow and channel-based model supporting parallel and cooperative computation. Formal behavioral semantics of this model is defined by Pi-calculus process algebra and formal properties of the proposed model are discussed. An application case is demonstrated to illustrate how the proposed model can be applied to describe services behavior and their interaction. The reachability analysis of the application case is performed based on modal -calculus. How the supporting tool, i.e. CWB-NC, can be utilized to verify the properties we anticipate is presented.

Trust-Based Service Management for Mobile Cloud IoT Systems

We propose and analyze a 3-tier cloud-cloudlet-device hierarchical trust-based service management protocol called IoT-HiTrust for large-scale mobile cloud Internet of Things (IoT) systems. Our mobile cloud hierarchical service management protocol allows an IoT customer to report its service experiences and query its subjective service trust score toward an IoT service provider following a scalable report-and-query design. We conduct a formal scalability analysis along with an ns-3 simulation performance analysis demonstrating that IoT-HiTrust not only achieves scalability without compromising accuracy, convergence, and resiliency properties against malicious attacks but also outperforms contemporary distributed and centralized IoT trust management protocols. We test the feasibility by applying IoT-HiTrust to two case studies: 1) a smart city travel service composition and binding application and 2) an air pollution detection and response application. The results demonstrate that IoT-HiTrust outperforms contemporary distributed and centralized trust-based IoT service management protocols in selecting trustworthy nodes to maximize application performance, while achieving scalability.

Trust-Based Service Management for Social Internet of Things Systems

A social internet of things (IoT) system can be viewed as a mix of traditional peer-to-peer networks and social networks, where “things” autonomously establish social relationships according to the owners’ social networks, and seek trusted “things” that can provide services needed when they come into contact with each other opportunistically. We propose and analyze the design notion of adaptive trust management for social IoT systems in which social relationships evolve dynamically among the owners of IoT devices. We reveal the design tradeoff between trust convergence versus trust fluctuation in our adaptive trust management protocol design. With our adaptive trust management protocol, a social IoT application can adaptively choose the best trust parameter settings in response to changing IoT social conditions such that not only trust assessment is accurate but also the application performance is maximized. We propose a table-lookup method to apply the analysis results dynamically and demonstrate the feasibility of our proposed adaptive trust management scheme with two real-world social IoT service composition applications.

Trust Management for SOA-Based IoT and Its Application to Service Composition

A future Internet of Things (IoT) system will connect the physical world into cyberspace everywhere and everything via billions of smart objects. On the one hand, IoT devices are physically connected via communication networks. The service oriented architecture (SOA) can provide interoperability among heterogeneous IoT devices in physical networks. On the other hand, IoT devices are virtually connected via social networks. In this paper we propose adaptive and scalable trust management to support service composition applications in SOA-based IoT systems. We develop a technique based on distributed collaborative filtering to select feedback using similarity rating of friendship, social contact, and community of interest relationships as the filter. Further we develop a novel adaptive filtering technique to determine the best way to combine direct trust and indirect trust dynamically to minimize convergence time and trust estimation bias in the presence of malicious nodes performing opportunistic service and collusion attacks. For scalability, we consider a design by which a capacity-limited node only keeps trust information of a subset of nodes of interest and performs minimum computation to update trust. We demonstrate the effectiveness of our proposed trust management through service composition application scenarios with a comparative performance analysis against EigenTrust and PeerTrust.

Optimizing the Reliability and Performance of Service Composition Applications with Fault Tolerance in Wireless Sensor Networks.

The services composition technology provides flexible methods for building service composition applications (SCAs) in wireless sensor networks (WSNs). The high reliability and high performance of SCAs help services composition technology promote the practical application of WSNs. The optimization methods for reliability and performance used for traditional software systems are mostly based on the instantiations of software components, which are inapplicable and inefficient in the ever-changing SCAs in WSNs. In this paper, we consider the SCAs with fault tolerance in WSNs. Based on a Universal Generating Function (UGF) we propose a reliability and performance model of SCAs in WSNs, which generalizes a redundancy optimization problem to a multi-state system. Based on this model, an efficient optimization algorithm for reliability and performance of SCAs in WSNs is developed based on a Genetic Algorithm (GA) to find the optimal structure of SCAs with fault-tolerance in WSNs. In order to examine the feasibility of our algorithm, we have evaluated the performance. Furthermore, the interrelationships between the reliability, performance and cost are investigated. In addition, a distinct approach to determine the most suitable parameters in the suggested algorithm is proposed.

A New Formal Modeling Method for Web Service Composition

With the rapid development of e-commerce, the application of web service composition is becoming increasingly important in many areas. If we apply unchecked web service composition, then we can only discover problems afterwards, and we have to devote unnecessary energy to repair. Here, formal modeling serves to be a premise to check. This paper brings up a formal modeling method for web service composition based on BDL (behavioral description language). The structure of this essay is to analyze the description of BPEL process, and we can get the formal model from the BPEL-to-BDL mapping relation.

An efficient and reliable approach for quality-of-service-aware service composition

With the rapidly increasing number of independently developed Web services that provide similar functionalities with varied quality of service (QoS), service composition is considered as a problem in the selection of component services that are in accordance with users’ QoS requirements; a practice known as the QoS-aware service composition problem. However, current solutions are unsuitable for most real-time decision-making service composition applications required to obtain a relatively optimal result within a reasonable amount of time. These services are also unreliable (or even risky) given the open service-oriented environment. In this paper, we address these problems and propose a novel heuristic algorithm for an efficient and reliable selection of trustworthy services in a service composition. The proposed algorithm consists of three steps. First, a trust-based selection method is used to filter untrustworthy component services. Second, convex hulls are constructed to reduce the search space in the process of service composition. Finally, a heuristic global optimization approach is used to obtain the near-optimal solution. The results demonstrate that our approach obtains a close-to-optimal and reliable solution within a reasonable computation time.

A Fault-Tolerant Method for Enhancing Reliability of Services Composition Application in WSNs Based on BPEL

In recent years, some approaches have been presented for the seamless integration of WSNs with the existing, widely deployed SOA technologies such as XML, Web services, and the Business Process Execution Language (BPEL) to build a wireless sensor networks service application. However, there a great challenge on fault tolerant in WSNs. In this paper, we present our framework and approach to enhance the reliability of service composition applications in WSNs through modeling and analyzing a wireless sensor networks service application based on BPEL with exception handler and compensation mechanism. At first, we analyze all possible states during the execution of BPEL instance in WSNs. Then, we present a state framework for modeling execution context in BPEL instance in WSNs. Based on this framework, we analyze state transition and operational semantics in the case of both correct execution and exceptional execution of BPEL instance in WSNs. Furthermore, we propose the state transition models for three types of activities in BPEL instance. In the end, we present a formal approach to model the execution context in BPEL for WSNs. Using this formal model, one can describe and analyze the control flow result from the exception handler and compensation mechanism in BPEL instance for WSNs.

A Fast Optimization Method for Reliability and Performance of Cloud Services Composition Application

At present the cloud computing is one of the newest trends of distributed computation, which is propelling another important revolution of software industry. The cloud services composition is one of the key techniques in software development. The optimization for reliability and performance of cloud services composition application, which is a typical stochastic optimization problem, is confronted with severe challenges due to its randomness and long transaction, as well as the characteristics of the cloud computing resources such as openness and dynamic. The traditional reliability and performance optimization techniques, for example, Markov model and state space analysis and so forth, have some defects such as being too time consuming and easy to cause state space explosion and unsatisfied the assumptions of component execution independence. To overcome these defects, we propose a fast optimization method for reliability and performance of cloud services composition application based on universal generating function and genetic algorithm in this paper. At first, a reliability and performance model for cloud service composition application based on the multiple state system theory is presented. Then the reliability and performance definition based on universal generating function is proposed. Based on this, a fast reliability and performance optimization algorithm is presented. In the end, the illustrative examples are given.

一种高效的服务组合优化算法

With the rapid increasing number of the independently developed web services that provide the same functionality but differ in quality of service (QoS), how to select corresponding component services for each task of a specific service composition process in the way that maximizes the aggregation QoS value, while satisfying the constraints set by the end-users is practice known as an NP hard problem. Current solutions are not suitable for most real-time decision-making service composition applications which are required to obtain an optimal result in reasonable time. In this paper, we present an approach which addresses the issue of this problem by constructing convex hulls. The proposed heuristic algorithm consists of two steps: first, convex hulls are constructed for reducing the search space, then the multi-objective optimization problem is solved based on M-HEU. The results of the experiments demonstrate that our approach can obtain a close-to-optimal solution in a reasonable amount of time.

Application of dynamic service composition in web question answering

Web Question Answering (WQA) and Web Service (WS) are parallel fields in intelligent web computing. In network services, they are used widely, and they are rarely combined together. For many intelligent web applications, however, using them together tends to be important. This paper based on the study of significant techniques of WQA, WS and Hierarchical Task Network (HTN), including Natural Language Processing (NLP), Web Service Ontology and a planner of HTN, gives a proposal of WQA framework. This framework combines NLP, predicate logic, Semantic Web description and an HTN planner-SHOP2, turning question answering into a planning problem by question mapping and service planning. It addresses a transition from natural language to semantic expression, composites web services dynamically by using SHOP2, and obtains the answering that meets customers' question by executing the web services sequence.

On Web Service Composition with QoS Constraint

The software architecture based on web service has become the critical technique to construct system in the distributed environments. The web service composition is the most important method to find the correct service in the complicated application circumstance. The key question is to find service based on the QoS and how to guarantee the quality. This thesis focuses the web service composition in order to get dynamic business cooperation and integration. The key component of web service is discussed and the method of web service composition is analyzed including the formalization verification and service composition architecture and the QoS-aware composition methods. Aimed at the application of web service composition, a method based on approved genetic algorithm is put forward. The simple genetic algorithm based web service composition has many problems such as slow convergence rate and non-optimal service composition. In this paper a genetic algorithm based on niche is provided for the Qos-aware composition and it can get more accurate service composition result and can get the optimal path quickly especially in the large scale problems according to the experiment.

Application of workflow-based service composition in E-government

To solve the information silo problem in the construction of E-government system,the authors put forward a frame based on workflow technology to implement service composition,which set up a process service center to compose the service of legacy system and implement the integration of legacy system and trans-departmental cooperative work.In this way,it could be suitable for the individual demand and realize quick response for business agility.Finally,a trans-departmental E-government system verifies the rationality of that frame,which suggests it is feasible and effective.

서비스 조합을 위한 XForms 기반의 모바일 사용자 인터페이스 개발

ABSTRACT As web services have become an important architecture solution, web service composition applications are developed actively. A mobile application supporting multiple services requires a complex user interface so that the interface needs to consist of more than one view and to provide a way to navigate between views. In this paper, we presented a formal way to analyze a set of views for a given service specification, and a relation model between views and methods. We then provided an algorithm to generate codes for service method calls and navigation between views. Therefore, with an optional user configuration input, we could automatically generated XForms codes from the web service specifications. Finally, we developed a proof of concept implementation of XForms browser to show that the generated codes works well as an interface for web service compositions.Keywords:Xforms, Service Composition, Mobile Presentation Framework 1. 서 론 1) REST(Representational State Transfer) 기반의 웹서비스[9]는 서비스 중심 아키텍춰(Service Oriented Architecture)를 구현하기 위한 가벼운 패러다임으로 광범위하게 사용되고 있다. REST 서비스는 가벼운 메시지 통신 방법으로서 개발이 간단하고 유연하여 모바일 환경에 적합하여 상황이나 장소에 따라 필요한 웹 기반의 서비스를 제공하는 어플리케이션 개발이 가능하다.

Iterative selection algorithm for service composition in distributed environments

In service oriented architecture (SOA), service composition is a promising way to create new services. However, some technical challenges are hindering the application of service composition. One of the greatest challenges for composite service provider is to select a set of services to instantiate composite service with end-to-end quality of service (QoS) assurance across different autonomous networks and business regions. This paper presents an iterative service selection algorithm for quality driven service composition. The algorithm runs on a peer-to-peer (P2P) service execution environment — distributed intelligent service execution (DISE), which provides scalable QoS registry, dynamic service selection and service execution services. The most significant feature of our iterative service selection algorithm is that it can work on a centralized QoS registry as well as cross decentralized ones. Network status is an optional factor in our QoS model and selection algorithm. The algorithm iteratively selects services following service execution order, so it can be applied either before service execution or at service run-time without any modification. We test our algorithm with a series of experiments on DISE. Experimental results illustrated its excellent selection and outstanding performance.