In any organization where SOA has been implemented, all of the web services are registered in UDDI and users’ needs are served by using appropriate web services. So in this paper, we will try to discover a service fr...In any organization where SOA has been implemented, all of the web services are registered in UDDI and users’ needs are served by using appropriate web services. So in this paper, we will try to discover a service from repository first that can provide the required output to the user. The process becomes difficult when a single service is not able to fulfill a user’s need and we need a combination of services to answer complex needs of users. In our paper, we will suggest a simpler approach for dynamic service composition using a graph based methodology. This will be a design time service composition. This approach uses the functional and non-functional parameters of the services to select the most suitable services for composition as per user’s need. This approach involves “service classification” on the basis of functional parameters, “service discovery” on the basis of user’s need and then “service composition” using the selected services on the basis of non-functional parameters like response time, cost, security and availability. Another challenge in SOA implementation is that, once the composition has performed, some services may become faulty at runtime and may stop the entire process of serving a user’s need. So, we will also describe a way of “dynamic service reconfiguration” in our approach that will enable us to identify and replace a faulty service that is violating the SLA or is not accessible anymore. This service reconfiguration is done without redoing or reconfiguring the entire composition. In the end, to simulate the proposed approach, we will represent a prototype application built on php 5.4 using My SQL database at backend.展开更多
In order to realize flexible, adaptable, extensible, efficient, and user-friendly service composition, we propose a service design oriented Web Service composite platform （SDOWSCP） and a service composition mechanis...In order to realize flexible, adaptable, extensible, efficient, and user-friendly service composition, we propose a service design oriented Web Service composite platform （SDOWSCP） and a service composition mechanism called composed-service-requestor-orient ed service composition （OBSDOSC）. SDOWSCP imports ontology into UDDI to define and annotate services in a flexible and intuitive manner and employs a concept of bond as a solution to the process heterogeneity. OBSDOSC is proposed in order to do some efforts to overcome some defects which current design tools usually have such as not user friendly and too professional. This paper proposes a pattern which describes the basic features of semi-automatic composite mode, discusses the whole lifetime of composed service and highlights how to lessen the descriptive heterogeneity and process heterogeneity and how to facilitate the design of composing a service.展开更多
This paper proposes a method of data-flow testing for Web services composition. Firstly, to facilitate data flow analysis and constraints collecting, the existing model representation of business process execution lan...This paper proposes a method of data-flow testing for Web services composition. Firstly, to facilitate data flow analysis and constraints collecting, the existing model representation of business process execution language （BPEL） is modified in company with the analysis of data dependency and an exact representation of dead path elimination （DPE） is proposed, which over-comes the difficulties brought to dataflow analysis. Then defining and using information based on data flow rules is collected by parsing BPEL and Web services description language （WSDL） documents and the def-use annotated control flow graph is created. Based on this model, data-flow anomalies which indicate potential errors can be discovered by traversing the paths of graph, and all-du-paths used in dynamic data flow testing for Web services composition are automatically generated, then testers can design the test cases according to the collected constraints for each path selected.展开更多
This paper proposes a dynamic Web service trust (WS Trust) model, and somecorresponding trust metric evaluation algorithms. The main goal is to evaluate the trustworthinessand predict the future bchaxiors of entities ...This paper proposes a dynamic Web service trust (WS Trust) model, and somecorresponding trust metric evaluation algorithms. The main goal is to evaluate the trustworthinessand predict the future bchaxiors of entities in oeder to help users find trustworthy Web serviceproviders and prevent users from providing unfair ratings against service providers.展开更多
For the problem of dynamic optimization in Web services composition, this paper presents a novel approach for selecting optimum Web services, which is based on the longest path method of weighted multistage graph. We ...For the problem of dynamic optimization in Web services composition, this paper presents a novel approach for selecting optimum Web services, which is based on the longest path method of weighted multistage graph. We propose and implement an Immune Algorithm for global optimization to construct composed Web services. Results of the experimentation illustrates that the algorithm in this paper has a powerful capability and can greatly improve the efficiency and veracity in service selection.展开更多
To solve the problem of chaining distributed geographic information Web services （GI Web services）, this paper provides an ontology-based method. With this method, semantic service description can be achieved by sem...To solve the problem of chaining distributed geographic information Web services （GI Web services）, this paper provides an ontology-based method. With this method, semantic service description can be achieved by semantic annotation of the elements in a Web service description language（WSDL） document with concepts of geographic ontology, and then a common under-standing about service semantics between customers and providers of Web services is built. Based on the decomposition and formalization of customer requirements, the discovery, composition and execution of GI Web services are explained in detail, and then a chaining of GI Web services is built and used to achieve the customer＇s requirement. Finally, an example based on Web ontology language for service （OWL-S） is provided for testing the feasibility of this method.展开更多
The concept and definition of trust degree of Web service is given. Evaluating trust degree of Web services with the method of neural network from the aspect of trust history sequence is proposed. The principle of the...The concept and definition of trust degree of Web service is given. Evaluating trust degree of Web services with the method of neural network from the aspect of trust history sequence is proposed. The principle of the method, applicable neural network structure, neural network construc ting, input standardization, training sample constructing, and the procedure of evaluating trust degree of Web services with trained neural network are described. Experiments show that it is feasible and effective to evaluate trust degree of Web Service with neural network.展开更多
It is essential to build a modern information management system to store and manage data of our circumlunar explorer in order to realize the scientific objectives. It is difficult for an information system based on tr...It is essential to build a modern information management system to store and manage data of our circumlunar explorer in order to realize the scientific objectives. It is difficult for an information system based on traditional distributed technology to communicate information and work together among heterogeneous systems in order to meet the new requirement of Internet development. XML and Web Services, because of their open standards and self-containing properties, have changed the mode of information organization and data management. Now they can provide a good solution for building an open, extendable, and compatible information management system, and facilitate interchanging and transferring of data among heterogeneous systems. On the basis of the three-tiered browse/server architectures and the Oracle 9i Database as an information storage platform, we have designed and implemented a data archiving and retrieval system for the circumlunar explorer-LUNARINFO. We have also successfully realized the integration between LUNARINFO and the cosmic dust database system. LUNARINFO consists of five function modules for data management, information publishing, system management, data retrieval, and interface integration. Based on XML and Web Services, it not only is an information database system for archiving, long-term storing, retrieving and publication of lunar reference data related to the circumlunar explorer, but also provides data web Services which can be easily developed by various expert groups and connected to the common information system to realize data resource integration.展开更多
Most of the existing approaches focus on identifying mismatches and synthesizing adaptors at design-time or recently at run-time. However, few works have been proposed to support adaptor reconfiguration when services ...Most of the existing approaches focus on identifying mismatches and synthesizing adaptors at design-time or recently at run-time. However, few works have been proposed to support adaptor reconfiguration when services in the composition evolve due to changes in business needs. To address the deficiencies, the problem of adaptor reconfiguration is targeted in the context of service composition. Firstly, the formal models for describing services and adaptors are presented. Then, under this formalization,the notion of reconfiguration compliance is proposed to determine the validity of an adaptor instance with respect to its history executions and future executions. Based on the notion,the algorithm for reconfiguration analysis of adaptors is presented and it can be used for determining the migratability of an adaptor instance and the corresponding target state of reconfiguration if migratable.Finally,feasibility of the proposed approach is validated on a realistic case study. The proposed approach improves the flexibility of adaptor-based service composition by equipping adaptors with reconfiguration capabilities.展开更多
目前软件应用广泛,对软件可靠性要求越来越高。近几年云计算技术的研究逐渐增多,对于云平台的可靠性技术也有了新的要求。Amazon Web Services(AWS)提供了一整套云计算服务,用户能够构建复杂、可扩展的应用程序。AWS在最小成本情况下,...目前软件应用广泛,对软件可靠性要求越来越高。近几年云计算技术的研究逐渐增多,对于云平台的可靠性技术也有了新的要求。Amazon Web Services(AWS)提供了一整套云计算服务,用户能够构建复杂、可扩展的应用程序。AWS在最小成本情况下,为用户提供了一套构建容错的软件系统平台。在技术和性能等多方面的优势,被业界广泛认可和接受。该文主要研究Amazon Web Services云平台中的核心组件是如何提供可靠性技术的,分别对核心组件Amazon EC2,Amazon Simple Storage(S3),Elastic Storage Block(EBS),Elastic Load Balancing,Auto Scaling进行研究分析,为以后云计算平台的搭建和可靠性技术的研究提供依据。展开更多
Performance anomaly detection is the process of identifying occurrences that do not conform to expected behavior or correlate with other incidents or events in time series data.Anomaly detection has been applied to ar...Performance anomaly detection is the process of identifying occurrences that do not conform to expected behavior or correlate with other incidents or events in time series data.Anomaly detection has been applied to areas such as fraud detection,intrusion detection systems,and network systems.In this paper,we propose an anomaly detection framework that uses dynamic features of quality of service that are collected in a simulated setup.Three variants of recurrent neural networks-SimpleRNN,long short term memory,and gated recurrent unit are evaluated.The results reveal that the proposed method effectively detects anomalies in web services with high accuracy.The performance of the proposed anomaly detection framework is superior to that of existing approaches using maximum accuracy and detection rate metrics.展开更多
文摘In any organization where SOA has been implemented, all of the web services are registered in UDDI and users’ needs are served by using appropriate web services. So in this paper, we will try to discover a service from repository first that can provide the required output to the user. The process becomes difficult when a single service is not able to fulfill a user’s need and we need a combination of services to answer complex needs of users. In our paper, we will suggest a simpler approach for dynamic service composition using a graph based methodology. This will be a design time service composition. This approach uses the functional and non-functional parameters of the services to select the most suitable services for composition as per user’s need. This approach involves “service classification” on the basis of functional parameters, “service discovery” on the basis of user’s need and then “service composition” using the selected services on the basis of non-functional parameters like response time, cost, security and availability. Another challenge in SOA implementation is that, once the composition has performed, some services may become faulty at runtime and may stop the entire process of serving a user’s need. So, we will also describe a way of “dynamic service reconfiguration” in our approach that will enable us to identify and replace a faulty service that is violating the SLA or is not accessible anymore. This service reconfiguration is done without redoing or reconfiguring the entire composition. In the end, to simulate the proposed approach, we will represent a prototype application built on php 5.4 using My SQL database at backend.
基金Supported by the National Key Technologies Re-search and Development Programming in the 10th Five-Year(2004BA721A05)
文摘In order to realize flexible, adaptable, extensible, efficient, and user-friendly service composition, we propose a service design oriented Web Service composite platform （SDOWSCP） and a service composition mechanism called composed-service-requestor-orient ed service composition （OBSDOSC）. SDOWSCP imports ontology into UDDI to define and annotate services in a flexible and intuitive manner and employs a concept of bond as a solution to the process heterogeneity. OBSDOSC is proposed in order to do some efforts to overcome some defects which current design tools usually have such as not user friendly and too professional. This paper proposes a pattern which describes the basic features of semi-automatic composite mode, discusses the whole lifetime of composed service and highlights how to lessen the descriptive heterogeneity and process heterogeneity and how to facilitate the design of composing a service.
基金the National Natural Science Foundation of China(60425206, 60503033)National Basic Research Program of China (973 Program, 2002CB312000)Opening Foundation of State Key Laboratory of Software Engineering in Wuhan University
文摘This paper proposes a method of data-flow testing for Web services composition. Firstly, to facilitate data flow analysis and constraints collecting, the existing model representation of business process execution language （BPEL） is modified in company with the analysis of data dependency and an exact representation of dead path elimination （DPE） is proposed, which over-comes the difficulties brought to dataflow analysis. Then defining and using information based on data flow rules is collected by parsing BPEL and Web services description language （WSDL） documents and the def-use annotated control flow graph is created. Based on this model, data-flow anomalies which indicate potential errors can be discovered by traversing the paths of graph, and all-du-paths used in dynamic data flow testing for Web services composition are automatically generated, then testers can design the test cases according to the collected constraints for each path selected.
基金Supported by the National Key Basic Research andDevelopment Program (973 Program G20000263)
文摘This paper proposes a dynamic Web service trust (WS Trust) model, and somecorresponding trust metric evaluation algorithms. The main goal is to evaluate the trustworthinessand predict the future bchaxiors of entities in oeder to help users find trustworthy Web serviceproviders and prevent users from providing unfair ratings against service providers.
基金Supported by the National Key Technologies Re-search and Development Programinthe 10th Five-Year Plan of China(2004BA721A05)
文摘For the problem of dynamic optimization in Web services composition, this paper presents a novel approach for selecting optimum Web services, which is based on the longest path method of weighted multistage graph. We propose and implement an Immune Algorithm for global optimization to construct composed Web services. Results of the experimentation illustrates that the algorithm in this paper has a powerful capability and can greatly improve the efficiency and veracity in service selection.
基金the National Natural Science Fundation ofChina (60774041)
文摘To solve the problem of chaining distributed geographic information Web services （GI Web services）, this paper provides an ontology-based method. With this method, semantic service description can be achieved by semantic annotation of the elements in a Web service description language（WSDL） document with concepts of geographic ontology, and then a common under-standing about service semantics between customers and providers of Web services is built. Based on the decomposition and formalization of customer requirements, the discovery, composition and execution of GI Web services are explained in detail, and then a chaining of GI Web services is built and used to achieve the customer＇s requirement. Finally, an example based on Web ontology language for service （OWL-S） is provided for testing the feasibility of this method.
基金Supported by the National Natural Science Foun-dation of China(60403027)the Natural Science Foundation of HubeiProvince (2005ABA258) the Open Foundation of State Key Labora-tory of Software Engineering(SKLSE05-07)
文摘The concept and definition of trust degree of Web service is given. Evaluating trust degree of Web services with the method of neural network from the aspect of trust history sequence is proposed. The principle of the method, applicable neural network structure, neural network construc ting, input standardization, training sample constructing, and the procedure of evaluating trust degree of Web services with trained neural network are described. Experiments show that it is feasible and effective to evaluate trust degree of Web Service with neural network.
文摘It is essential to build a modern information management system to store and manage data of our circumlunar explorer in order to realize the scientific objectives. It is difficult for an information system based on traditional distributed technology to communicate information and work together among heterogeneous systems in order to meet the new requirement of Internet development. XML and Web Services, because of their open standards and self-containing properties, have changed the mode of information organization and data management. Now they can provide a good solution for building an open, extendable, and compatible information management system, and facilitate interchanging and transferring of data among heterogeneous systems. On the basis of the three-tiered browse/server architectures and the Oracle 9i Database as an information storage platform, we have designed and implemented a data archiving and retrieval system for the circumlunar explorer-LUNARINFO. We have also successfully realized the integration between LUNARINFO and the cosmic dust database system. LUNARINFO consists of five function modules for data management, information publishing, system management, data retrieval, and interface integration. Based on XML and Web Services, it not only is an information database system for archiving, long-term storing, retrieving and publication of lunar reference data related to the circumlunar explorer, but also provides data web Services which can be easily developed by various expert groups and connected to the common information system to realize data resource integration.
基金National Natural Science Foundations of China(Nos.61272083,61262002,61170043)China Postdoctoral Science Foundation(Nos.20110491411,2014M562177)The Science Foundations of Nanjing Institute of Technology,China(Nos.QKJB201304,YKJ201420)
文摘Most of the existing approaches focus on identifying mismatches and synthesizing adaptors at design-time or recently at run-time. However, few works have been proposed to support adaptor reconfiguration when services in the composition evolve due to changes in business needs. To address the deficiencies, the problem of adaptor reconfiguration is targeted in the context of service composition. Firstly, the formal models for describing services and adaptors are presented. Then, under this formalization,the notion of reconfiguration compliance is proposed to determine the validity of an adaptor instance with respect to its history executions and future executions. Based on the notion,the algorithm for reconfiguration analysis of adaptors is presented and it can be used for determining the migratability of an adaptor instance and the corresponding target state of reconfiguration if migratable.Finally,feasibility of the proposed approach is validated on a realistic case study. The proposed approach improves the flexibility of adaptor-based service composition by equipping adaptors with reconfiguration capabilities.
文摘Performance anomaly detection is the process of identifying occurrences that do not conform to expected behavior or correlate with other incidents or events in time series data.Anomaly detection has been applied to areas such as fraud detection,intrusion detection systems,and network systems.In this paper,we propose an anomaly detection framework that uses dynamic features of quality of service that are collected in a simulated setup.Three variants of recurrent neural networks-SimpleRNN,long short term memory,and gated recurrent unit are evaluated.The results reveal that the proposed method effectively detects anomalies in web services with high accuracy.The performance of the proposed anomaly detection framework is superior to that of existing approaches using maximum accuracy and detection rate metrics.
