As a new promising paradigm, cloud computing can make good use of economics of scale and elastically deliver almost any IT related services on demand. Nevertheless, one of the key problems remaining in cloud computing...As a new promising paradigm, cloud computing can make good use of economics of scale and elastically deliver almost any IT related services on demand. Nevertheless, one of the key problems remaining in cloud computing is related to virtual machine images, which require a great amount of space/time to reposit/provision, especially with diverse requests from thousands of users simultaneously. In this paper, by using the splitting and eliminating redundant data techniques, a space and time efficient approach for virtual machines is proposed. The experiments demonstrate that, compared with existing solutions, our approach can conserve more disk space and speed up the provisioning of virtual machines.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
Web service （WS） is an emerging software technology, especially acting an important role in cloud computing. The WS choreography description language （WS-CDL） is the standard for modeling the observable behavior o...Web service （WS） is an emerging software technology, especially acting an important role in cloud computing. The WS choreography description language （WS-CDL） is the standard for modeling the observable behavior of WS composition across multiple participants from a global point of view. However, it lacks of a formal semantics and could easily lead to misunderstanding and different implementations. In this paper, the WS-CDL based specifications are formally extracted in a communicating sequential process supporting a formal approach to checking WS models. In addition, formalisms and model checking are explicitly illustrated through a simple but non-trivial example with the help of model checker process analysis toolkit （PAT）.展开更多
基金Project supported by the Shanghai Leading Academic Discipline Project(Grant No.J50103)the Natural Science Foundation of Shanghai Municipality(Grant No.10Z1411600)+1 种基金the Innovation Foundation of Shanghai Municipal Education Commission(Grant No.10YZ18)the National Science and Technology Major Project(Grant No.LX101102103)
文摘As a new promising paradigm, cloud computing can make good use of economics of scale and elastically deliver almost any IT related services on demand. Nevertheless, one of the key problems remaining in cloud computing is related to virtual machine images, which require a great amount of space/time to reposit/provision, especially with diverse requests from thousands of users simultaneously. In this paper, by using the splitting and eliminating redundant data techniques, a space and time efficient approach for virtual machines is proposed. The experiments demonstrate that, compared with existing solutions, our approach can conserve more disk space and speed up the provisioning of virtual machines.
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.
基金supported by the Shanghai Leading Academic Discipline Project (Grant No.J50103)
文摘Web service （WS） is an emerging software technology, especially acting an important role in cloud computing. The WS choreography description language （WS-CDL） is the standard for modeling the observable behavior of WS composition across multiple participants from a global point of view. However, it lacks of a formal semantics and could easily lead to misunderstanding and different implementations. In this paper, the WS-CDL based specifications are formally extracted in a communicating sequential process supporting a formal approach to checking WS models. In addition, formalisms and model checking are explicitly illustrated through a simple but non-trivial example with the help of model checker process analysis toolkit （PAT）.
