In order to enable quality-aware web services selection in the process of service composition,this paper first describes the non-functional requirements of service consumers and the quality of elementary service or co...In order to enable quality-aware web services selection in the process of service composition,this paper first describes the non-functional requirements of service consumers and the quality of elementary service or composite service as a quality vector,and then models the QoS（quality of service）-aware composition as a multiple criteria optimization problem in extending directed graph.A novel simulated annealing algorithm for QoS-aware web services composition is presented.A normalizing for composite service QoS values is made,and a secondary iterative optimization is used in the algorithm.Experimental results show that the simulated annealing algorithm can satisfy the multiple criteria and global QoS requirements of service consumers.The algorithm produces near optimum solution with much less computation cost.展开更多
To address the problem of web services selection based on quality, an approach of multi-attribute group decision making algorithm is proposed. Based on the Borda social choice function, the group decision making algor...To address the problem of web services selection based on quality, an approach of multi-attribute group decision making algorithm is proposed. Based on the Borda social choice function, the group decision making algorithm aggregates the results of multiple methods with different principles which are used to obtain constantly changing quality of service, thus increasing the confidence to select the most appropriate web service for a special task. The experimental results indicate that the proposed approach has better scalability and can be applied to large-scale distributed service computing environments. It is also shown that the proposed group decision making approach can effectively optimize the services selection and outperforms the random and robin policies. By using this approach, it can extend a method to obtain constantly changing quality of service and construct a synthetic information entity with multi-level knowledge, which guarantees the accuracy of services selection.展开更多
The non-functional QoS (quality of service) information helps us to select a proper Web-service from the web applications, by using component services such as UDDI[1](Universal Description, Discovery, and Integration)...The non-functional QoS (quality of service) information helps us to select a proper Web-service from the web applications, by using component services such as UDDI[1](Universal Description, Discovery, and Integration) and MDS(Monitoring and Discovery System). MDS is a suite of web services to monitor and discover resources and service on Grids, but MDS only based on function aspects. This paper studies on an approach to provide the QoS information and a discovery model by using MDS and gives a system deployment and implementation plan. The simulation results show that the method is effective in service discovery.展开更多
Cloud computing is becoming a hot topic of the information industry in recent years. Many companies provide the cloud services, such as Google Apps and Apple multimedia services. In general, by applying the virtulizat...Cloud computing is becoming a hot topic of the information industry in recent years. Many companies provide the cloud services, such as Google Apps and Apple multimedia services. In general, by applying the virtulization technologies, the data center is built for cloud computing to provide users with the eomputing and storage resources, as well as the software environment. Thus, the quality of service （QoS） must be considered to satisfy users＇ requirements. This paper proposes a high efficiency scheduling scheme for supporting cloud computing. The virtual machine migration technique has been applied to the proposed scheduling scheme for improving the resources utilization and satisfying the QoS requirement of users. The experimental results show that in addition to satisfying the QoS requirement of users, the proposed scheme can improve the resources utilization effectively.展开更多
Cloud computing is high technology, which fulfills needs of common as well as enterprise level to meet their information and communication technology requirements and so on. Cloud computing extends existing informatio...Cloud computing is high technology, which fulfills needs of common as well as enterprise level to meet their information and communication technology requirements and so on. Cloud computing extends existing information technology capabilities and requirements. Many technologies are being merged with cloud computing, same as that orchestrations can boost cloud service provisioning process. The usage of orchestrations can play vital role to provision cloud services. Cloud service providers can create scalable cloud services at low cost by organizing cloud infrastructure by using cloud orchestrations. Dynamic orchestration flows can generate required cloud computing services to meet service level agreements and quality of services. There is a need to understand issues and barriers involved to integrate cloud orchestrations with cloud service provisioning process. There is also need to understand business related problems bordering cloud computing technology. There is much capacity to do targeted research work for cloud orchestrations and its integration with service level agreements as well as with SLI (service level integration) layer. In this article we have elaborated detailed analysis and identified a number of issues that will affect the cloud service users as well as cloud service providers and cloud service provisioning system. We are defining an approach to orchestrate cloud infrastructure by using orchestration flows, to generate cloud services in order to meet service level agreements and quality of standard.展开更多
Due to a rapid increase in the number of functionally equivalent web services at open and dynamic Io T service environment,Qo S has become a major discrimination factor to reflect the user's expectation and experi...Due to a rapid increase in the number of functionally equivalent web services at open and dynamic Io T service environment,Qo S has become a major discrimination factor to reflect the user's expectation and experience of using a service.There are different languages and models for expressing Qo S advertisements and requirements among service providers and consumers.Therefore,it leads to the issues of semantic interoperability of Qo S information and semantic similarity match between a semantic description of the service being requested by the service consumer,and a formal description of the service being offered by the service provider.In this paper,we propose a hierarchical two-layer semantic Qo S ontology to promote the description and declaration of Qo S-based service information in detail for any domain and application.And,we develop a semantic matchmaking algorithm to compare the web services according to their Qo S information and adopt analytical hierarchy process( AHP) to make decision for the ranked services depending on the Qo S criteria.The comparison study and experimental result show that our proposed system is superior to other service ranking approaches.展开更多
In order to support CSCW (Computer Supported Cooperative Work) applications, some basic technologies must be introduced into the computer supported environment. They are shared workspace, work management and interacti...In order to support CSCW (Computer Supported Cooperative Work) applications, some basic technologies must be introduced into the computer supported environment. They are shared workspace, work management and interaction among participants. Computer communication is essential and important for these technologies. In this paper, we will discuss different kinds of communication services required by CSCW. There are three communication styles in CSCW support environment: real time stream transfer, real time block transfer and non real time transfer. These communication services require different QoS quality of service parameters. The architecture of QoS is then analyzed and a framework of a QoS guaranteed communication service platform is proposed.展开更多
With the rapid growth of service scale, there are many services with the same functional properties but different non-flmctional properties on the Internet. There have been some global optimizing service selection alg...With the rapid growth of service scale, there are many services with the same functional properties but different non-flmctional properties on the Internet. There have been some global optimizing service selection algorithms for service selection. However, most of those approaches cannot fully reflect users＇ preferences or are not fully suitable for large-scale services selection. In this paper, an ant colony optimization （ACO） algorithm for the model of global optimizing service selection with various quality of srevice （QoS） properties is employed, and a user-preference based large-scale service selection algorithm is proposed. This algorithm aims at optimizing user-preferred QoS properties and selecting services that meet all user-defined QoS thresholds. Experiment results prove that this algorithm is very efficient in this regard.展开更多
Recent advancements in cloud computing(CC)technologies signified that several distinct web services are presently developed and exist at the cloud data centre.Currently,web service composition gains maximum attention ...Recent advancements in cloud computing(CC)technologies signified that several distinct web services are presently developed and exist at the cloud data centre.Currently,web service composition gains maximum attention among researchers due to its significance in real-time applications.Quality of Service(QoS)aware service composition concerned regarding the election of candidate services with the maximization of the whole QoS.But these models have failed to handle the uncertainties of QoS.The resulting QoS of composite service identified by the clients become unstable and subject to risks of failing composition by end-users.On the other hand,trip planning is an essential technique in supporting digital map services.It aims to determine a set of location based services(LBS)which cover all client intended activities quantified in the query.But the available web service composition solutions do not consider the complicated spatio-temporal features.For resolving this issue,this study develops a new hybridization of the firefly optimization algorithm with fuzzy logic based web service composition model(F3L-WSCM)in a cloud environment for location awareness.The presented F3L-WSCM model involves a discovery module which enables the client to provide a query related to trip planning such as flight booking,hotels,car rentals,etc.At the next stage,the firefly algorithm is applied to generate composition plans to minimize the number of composition plans.Followed by,the fuzzy subtractive clustering(FSC)will select the best composition plan from the available composite plans.Besides,the presented F3L-WSCM model involves four input QoS parameters namely service cost,service availability,service response time,and user rating.An extensive experimental analysis takes place on CloudSim tool and exhibit the superior performance of the presented F3L-WSCM model in terms of accuracy,execution time,and efficiency.展开更多
Web Service是目前研究界和产业界广泛关注的技术之一.随着Web Service的广泛应用,研究者们普遍认识到,服务的非功能属性,即服务质量(Quality of Service,QoS)是面向服务的应用能否成功的关键因素之一.因此,研究者们尝试从多个角度对Qo...Web Service是目前研究界和产业界广泛关注的技术之一.随着Web Service的广泛应用,研究者们普遍认识到,服务的非功能属性,即服务质量(Quality of Service,QoS)是面向服务的应用能否成功的关键因素之一.因此,研究者们尝试从多个角度对QoS相关问题展开了研究.然而,现有工作普遍关注基于QoS的动态服务选择和组装等上层应用技术,而对于如何获取、存储、度量QoS等基础支持技术研究较少,而这些基础性工作对QoS相关的研究工作具有显著的重要性.此外,不同应用领域对Web Service QoS的需求不尽相同,因此,需要有一套灵活的机制支持在QoS模型定义、QoS度量方法、QoS信息采集等方面体现出的领域特性.针对这个问题,文中提出了一个可扩展的Web Service QoS信息管理框架,详细分析了该框架涉及到的重要方法与核心技术,并给出了该框架在北京大学软件构件库系统中的设计决策和方案.最后,介绍了文中框架在一个863计划项目中的应用实例,该实例展示了用户根据其应用的领域需求对本框架进行扩展并进行Web Service QoS管理的方法,从而验证了本管理框架的可扩展性及实用性.展开更多
基金The National Natural Science Foundation of China(No.60773217)Free Exploration Project(985 Project of Renmin University of China)(No.21361231)
文摘In order to enable quality-aware web services selection in the process of service composition,this paper first describes the non-functional requirements of service consumers and the quality of elementary service or composite service as a quality vector,and then models the QoS（quality of service）-aware composition as a multiple criteria optimization problem in extending directed graph.A novel simulated annealing algorithm for QoS-aware web services composition is presented.A normalizing for composite service QoS values is made,and a secondary iterative optimization is used in the algorithm.Experimental results show that the simulated annealing algorithm can satisfy the multiple criteria and global QoS requirements of service consumers.The algorithm produces near optimum solution with much less computation cost.
文摘To address the problem of web services selection based on quality, an approach of multi-attribute group decision making algorithm is proposed. Based on the Borda social choice function, the group decision making algorithm aggregates the results of multiple methods with different principles which are used to obtain constantly changing quality of service, thus increasing the confidence to select the most appropriate web service for a special task. The experimental results indicate that the proposed approach has better scalability and can be applied to large-scale distributed service computing environments. It is also shown that the proposed group decision making approach can effectively optimize the services selection and outperforms the random and robin policies. By using this approach, it can extend a method to obtain constantly changing quality of service and construct a synthetic information entity with multi-level knowledge, which guarantees the accuracy of services selection.
文摘The non-functional QoS (quality of service) information helps us to select a proper Web-service from the web applications, by using component services such as UDDI[1](Universal Description, Discovery, and Integration) and MDS(Monitoring and Discovery System). MDS is a suite of web services to monitor and discover resources and service on Grids, but MDS only based on function aspects. This paper studies on an approach to provide the QoS information and a discovery model by using MDS and gives a system deployment and implementation plan. The simulation results show that the method is effective in service discovery.
文摘Cloud computing is becoming a hot topic of the information industry in recent years. Many companies provide the cloud services, such as Google Apps and Apple multimedia services. In general, by applying the virtulization technologies, the data center is built for cloud computing to provide users with the eomputing and storage resources, as well as the software environment. Thus, the quality of service （QoS） must be considered to satisfy users＇ requirements. This paper proposes a high efficiency scheduling scheme for supporting cloud computing. The virtual machine migration technique has been applied to the proposed scheduling scheme for improving the resources utilization and satisfying the QoS requirement of users. The experimental results show that in addition to satisfying the QoS requirement of users, the proposed scheme can improve the resources utilization effectively.
文摘Cloud computing is high technology, which fulfills needs of common as well as enterprise level to meet their information and communication technology requirements and so on. Cloud computing extends existing information technology capabilities and requirements. Many technologies are being merged with cloud computing, same as that orchestrations can boost cloud service provisioning process. The usage of orchestrations can play vital role to provision cloud services. Cloud service providers can create scalable cloud services at low cost by organizing cloud infrastructure by using cloud orchestrations. Dynamic orchestration flows can generate required cloud computing services to meet service level agreements and quality of services. There is a need to understand issues and barriers involved to integrate cloud orchestrations with cloud service provisioning process. There is also need to understand business related problems bordering cloud computing technology. There is much capacity to do targeted research work for cloud orchestrations and its integration with service level agreements as well as with SLI (service level integration) layer. In this article we have elaborated detailed analysis and identified a number of issues that will affect the cloud service users as well as cloud service providers and cloud service provisioning system. We are defining an approach to orchestrate cloud infrastructure by using orchestration flows, to generate cloud services in order to meet service level agreements and quality of standard.
基金Sponsored by the Scientific Research Foundation of NJUPT(Grant No.NY209017,NY211108,and NYKL201105)Huawei Company(Grant No.YB2014010003(Project IRP-2013-08-06))
文摘Due to a rapid increase in the number of functionally equivalent web services at open and dynamic Io T service environment,Qo S has become a major discrimination factor to reflect the user's expectation and experience of using a service.There are different languages and models for expressing Qo S advertisements and requirements among service providers and consumers.Therefore,it leads to the issues of semantic interoperability of Qo S information and semantic similarity match between a semantic description of the service being requested by the service consumer,and a formal description of the service being offered by the service provider.In this paper,we propose a hierarchical two-layer semantic Qo S ontology to promote the description and declaration of Qo S-based service information in detail for any domain and application.And,we develop a semantic matchmaking algorithm to compare the web services according to their Qo S information and adopt analytical hierarchy process( AHP) to make decision for the ranked services depending on the Qo S criteria.The comparison study and experimental result show that our proposed system is superior to other service ranking approaches.
文摘In order to support CSCW (Computer Supported Cooperative Work) applications, some basic technologies must be introduced into the computer supported environment. They are shared workspace, work management and interaction among participants. Computer communication is essential and important for these technologies. In this paper, we will discuss different kinds of communication services required by CSCW. There are three communication styles in CSCW support environment: real time stream transfer, real time block transfer and non real time transfer. These communication services require different QoS quality of service parameters. The architecture of QoS is then analyzed and a framework of a QoS guaranteed communication service platform is proposed.
基金Project supported by the Shanghai Leading Academic Discipline Project(Grant No.J50103)the Natural Science Foundation of Shanghai Municipality(Grant No.10ZR1411600)+1 种基金the Innovation Program of Education Commission of Shanghai Municipality(Grant No.10TX18)the New Generation Broadband Wireless Mobile Communication Network Key Technologies Research and Development Program of China 2010
文摘With the rapid growth of service scale, there are many services with the same functional properties but different non-flmctional properties on the Internet. There have been some global optimizing service selection algorithms for service selection. However, most of those approaches cannot fully reflect users＇ preferences or are not fully suitable for large-scale services selection. In this paper, an ant colony optimization （ACO） algorithm for the model of global optimizing service selection with various quality of srevice （QoS） properties is employed, and a user-preference based large-scale service selection algorithm is proposed. This algorithm aims at optimizing user-preferred QoS properties and selecting services that meet all user-defined QoS thresholds. Experiment results prove that this algorithm is very efficient in this regard.
文摘Recent advancements in cloud computing(CC)technologies signified that several distinct web services are presently developed and exist at the cloud data centre.Currently,web service composition gains maximum attention among researchers due to its significance in real-time applications.Quality of Service(QoS)aware service composition concerned regarding the election of candidate services with the maximization of the whole QoS.But these models have failed to handle the uncertainties of QoS.The resulting QoS of composite service identified by the clients become unstable and subject to risks of failing composition by end-users.On the other hand,trip planning is an essential technique in supporting digital map services.It aims to determine a set of location based services(LBS)which cover all client intended activities quantified in the query.But the available web service composition solutions do not consider the complicated spatio-temporal features.For resolving this issue,this study develops a new hybridization of the firefly optimization algorithm with fuzzy logic based web service composition model(F3L-WSCM)in a cloud environment for location awareness.The presented F3L-WSCM model involves a discovery module which enables the client to provide a query related to trip planning such as flight booking,hotels,car rentals,etc.At the next stage,the firefly algorithm is applied to generate composition plans to minimize the number of composition plans.Followed by,the fuzzy subtractive clustering(FSC)will select the best composition plan from the available composite plans.Besides,the presented F3L-WSCM model involves four input QoS parameters namely service cost,service availability,service response time,and user rating.An extensive experimental analysis takes place on CloudSim tool and exhibit the superior performance of the presented F3L-WSCM model in terms of accuracy,execution time,and efficiency.
文摘通过网络提供服务的Web Service的服务质量会随着网络环境、服务器负载等因素的变化而变化,如何更好地帮助用户选择在未来一段时间内符合服务质量需求的Web Service,是目前服务计算领域中需要解决的关键问题之一。针对上述问题,提出了一种基于时间序列分析的Web Service QoS预测方法,并实现了相应的Web Service QoS自动预测工具。该工具能够根据Web Service的历史QoS数据,有效地预测未来短期内的QoS信息。以17832个Web Service的历史数据为基础,设计了相关实验,并验证了方法的有效性。
文摘Web Service是目前研究界和产业界广泛关注的技术之一.随着Web Service的广泛应用,研究者们普遍认识到,服务的非功能属性,即服务质量(Quality of Service,QoS)是面向服务的应用能否成功的关键因素之一.因此,研究者们尝试从多个角度对QoS相关问题展开了研究.然而,现有工作普遍关注基于QoS的动态服务选择和组装等上层应用技术,而对于如何获取、存储、度量QoS等基础支持技术研究较少,而这些基础性工作对QoS相关的研究工作具有显著的重要性.此外,不同应用领域对Web Service QoS的需求不尽相同,因此,需要有一套灵活的机制支持在QoS模型定义、QoS度量方法、QoS信息采集等方面体现出的领域特性.针对这个问题,文中提出了一个可扩展的Web Service QoS信息管理框架,详细分析了该框架涉及到的重要方法与核心技术,并给出了该框架在北京大学软件构件库系统中的设计决策和方案.最后,介绍了文中框架在一个863计划项目中的应用实例,该实例展示了用户根据其应用的领域需求对本框架进行扩展并进行Web Service QoS管理的方法,从而验证了本管理框架的可扩展性及实用性.
