In recent years, Web services and Peer-to-Peer (or simply P2P) appear as two of the hottest research topics in network computing. On the one hand, by adopting a decentralized, network-based style, P2P technologies can...In recent years, Web services and Peer-to-Peer (or simply P2P) appear as two of the hottest research topics in network computing. On the one hand, by adopting a decentralized, network-based style, P2P technologies can make P2P systems enhance overall reliability and fault-tolerance, increase autonomy, and enable ad-hoc communication and collaboration. On the other hand, Web services provides a good approach to integrate various heterogeneous systems and applications into a cooperative environment. This paper presents the techniques of combining Web services and P2P technologies into GIS to construct a new generation of GIS, which is more flexible and cooperative. As a case study, an ongoing project JGWS is introduced, which is an experimental GIS Web services platform built on JXTA. This paper also explores the schemes of building GIS Web services in a P2P environment.展开更多
Network security policy and the automated refinement of its hierarchies aims to simplify the administration of security services in complex network environments. The semantic gap between the policy hierarchies reflect...Network security policy and the automated refinement of its hierarchies aims to simplify the administration of security services in complex network environments. The semantic gap between the policy hierarchies reflects the validity of the policy hierarchies yielded by the automated policy refinement process. However, little attention has been paid to the evaluation of the compliance between the derived lower level policy and the higher level policy. We present an ontology based on Ontology Web Language （OWL） to describe the semantics of security policy and their implementation. We also propose a method of estimating the semantic similarity between a given展开更多
Service composition is considered to be an effective way for resource sharing and node collaboration in Mobile Ad hoc NETworks (MANETs) environment.In order to improve the reliability and shorten the response time of ...Service composition is considered to be an effective way for resource sharing and node collaboration in Mobile Ad hoc NETworks (MANETs) environment.In order to improve the reliability and shorten the response time of composite services,this paper first analyzes the node environments and network environments that affect the component services' availability,and then proposes an Environment-aware Quantitative Evaluation Model for Service Availability (EQEM-SA).In addition,based on EQEM-SA,a service field concept is proposed as well as the availability attenuation equation,where the availability value is considered as the field strength.Then the service selection approach based on service field model is presented.The effectiveness of the proposed approach is illustrated and compared with related references,and the results of experimental evaluations indicate that our approach significantly reduces the failure rate and shortens the service delay.展开更多
Along with the rapid development of communications,the Internet,and smart terminals,mobile Internet has become a hot topic with both opportunities and challenges.In this article,a new perspective on edge content deliv...Along with the rapid development of communications,the Internet,and smart terminals,mobile Internet has become a hot topic with both opportunities and challenges.In this article,a new perspective on edge content delivery service for mobile Internet is described,based on cooperating terminals.A mobile cloud architecture named Cloudlet Aided Cooperative Terminals Service Environment(CACTSE) is proposed as an edge network service environment.The Service Manager(SM),a cloudlet like module,is introduced into the local service domain in order to manage the in-domain terminals and help coordinate the content delivery requests for better bandwidth efficiency as well as user experience.The reference model is presented in this article with architecture and mechanism design.Moreover,the research progress and potential technology trends of CACTSE are analysed based on the related R&D directions.展开更多
This paper summarizes the requirements for modem maritime wireless communication networks in the marine environments including the sea- to-sea and sea-to-shore communication scenarios. The existing maritime wireless c...This paper summarizes the requirements for modem maritime wireless communication networks in the marine environments including the sea- to-sea and sea-to-shore communication scenarios. The existing maritime wireless communication sys- tems are presented and the development of the state-of-the-art maritime communication systems is surveyed. Furthermore, a hierarchical and integrated maritime network architecture is proposed to satisfy the increasing various classes of services which demand different Quality of Service （QoS）. Finally, the open issues for further development of maritime communications are identified.展开更多
WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System （ColTS）. However, the mobility of...WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System （ColTS）. However, the mobility of nodes makes data dissemination a hard nut to crack. In this paper, we propose MSDD, a multiple mobile sinks data dissemination mechanism for solving the dissemination problem. The main ideas of MSDD are constructing a two-tier grid structure by a designated sink, exploiting a hierarchical monitoring mechanism, and employing a global agent to track the sink locations in order to make the emergencies reported to the sinks immediately, In addition, MSDD supports the query-driven data dissemination. Being compared with TTDD, MSDD is theoretically proved to have less communication overhead. We also validate MSDD outperforms TTDD in reliability and the emergency delivery latency bv simulations.展开更多
In the network environment, changes of resources structure, information technology and users requirements of standards library cause series of problems such as unobvious effect of services, low efficiency of resource ...In the network environment, changes of resources structure, information technology and users requirements of standards library cause series of problems such as unobvious effect of services, low efficiency of resource utilization, poor innovation ability, etc. And we point out the problems and challenges faced by traditional standards library in the network environment. The standards library must redesign the organization structure and business process radically so that standards library could improve the service model, enhance the service quality and utilization rate of various document resources.展开更多
基金Acknowledgements： This work is supported by the National Research Foundation for the Doctoral Program of Higher Education of China under Grant No. 20020001015： the National Grand Fundamental Research 973 Program of China under Grant No.2002CB312000 the National Science Foundation of China under Grant No.60073016 and No.60203002+1 种基金 the National High Technology Development 863 Program under Grant No. 2002AA 135330, No. 2002AA 134030 and No. 2001AAI 13151 the Beijing Science Foundation under Grant No.4012007.
文摘In recent years, Web services and Peer-to-Peer (or simply P2P) appear as two of the hottest research topics in network computing. On the one hand, by adopting a decentralized, network-based style, P2P technologies can make P2P systems enhance overall reliability and fault-tolerance, increase autonomy, and enable ad-hoc communication and collaboration. On the other hand, Web services provides a good approach to integrate various heterogeneous systems and applications into a cooperative environment. This paper presents the techniques of combining Web services and P2P technologies into GIS to construct a new generation of GIS, which is more flexible and cooperative. As a case study, an ongoing project JGWS is introduced, which is an experimental GIS Web services platform built on JXTA. This paper also explores the schemes of building GIS Web services in a P2P environment.
基金the National Natural Science Foundation of China
文摘Network security policy and the automated refinement of its hierarchies aims to simplify the administration of security services in complex network environments. The semantic gap between the policy hierarchies reflects the validity of the policy hierarchies yielded by the automated policy refinement process. However, little attention has been paid to the evaluation of the compliance between the derived lower level policy and the higher level policy. We present an ontology based on Ontology Web Language （OWL） to describe the semantics of security policy and their implementation. We also propose a method of estimating the semantic similarity between a given
基金supported in part by the National Key Basic Research Program of China(Grant Nos.2009CB320406and2009CB320504)Foundation for Innovative Research Groups of the National Natural Science Foundation of China(Grant No.60821001)National Natural Science Foundation of China(Grant No.61070206)
文摘Service composition is considered to be an effective way for resource sharing and node collaboration in Mobile Ad hoc NETworks (MANETs) environment.In order to improve the reliability and shorten the response time of composite services,this paper first analyzes the node environments and network environments that affect the component services' availability,and then proposes an Environment-aware Quantitative Evaluation Model for Service Availability (EQEM-SA).In addition,based on EQEM-SA,a service field concept is proposed as well as the availability attenuation equation,where the availability value is considered as the field strength.Then the service selection approach based on service field model is presented.The effectiveness of the proposed approach is illustrated and compared with related references,and the results of experimental evaluations indicate that our approach significantly reduces the failure rate and shortens the service delay.
基金supported by the "New Generation Broadband Wireless Mobile Communication Network"Key Project under Grant No. 2011ZX03005004-02the National Natural Science Foundation of China under Grants No. 60971125,No.61101119+2 种基金the Funds for Creative Research Groups of China under Grant No. 61121001the European Commission FP7 Project EVANS under Grant No. 2010-269323the Program for Changjiang Scholars and Innovative Research Team in University of China under Grant No. IRT1049
文摘Along with the rapid development of communications,the Internet,and smart terminals,mobile Internet has become a hot topic with both opportunities and challenges.In this article,a new perspective on edge content delivery service for mobile Internet is described,based on cooperating terminals.A mobile cloud architecture named Cloudlet Aided Cooperative Terminals Service Environment(CACTSE) is proposed as an edge network service environment.The Service Manager(SM),a cloudlet like module,is introduced into the local service domain in order to manage the in-domain terminals and help coordinate the content delivery requests for better bandwidth efficiency as well as user experience.The reference model is presented in this article with architecture and mechanism design.Moreover,the research progress and potential technology trends of CACTSE are analysed based on the related R&D directions.
基金the "Program for Promoting Maritime Economies with Science and Technology" in Tianjin，the National Natural Science Foundation of China，the Tianjin Research Program of Application Foundation and Advanced Technology，the National Science and Technology Major Project，Seed Foundation of Tianjin University
文摘This paper summarizes the requirements for modem maritime wireless communication networks in the marine environments including the sea- to-sea and sea-to-shore communication scenarios. The existing maritime wireless communication sys- tems are presented and the development of the state-of-the-art maritime communication systems is surveyed. Furthermore, a hierarchical and integrated maritime network architecture is proposed to satisfy the increasing various classes of services which demand different Quality of Service （QoS）. Finally, the open issues for further development of maritime communications are identified.
基金This work was supported in part by China National Natural Science Foundation under Grant 61271185,and the Fundamental Research Funds for the Central Universities
文摘WSN has been developing from traditional environment monitoring applications to the ubiquitous information services such as the Congestion-oriented Intelligent Transportation System （ColTS）. However, the mobility of nodes makes data dissemination a hard nut to crack. In this paper, we propose MSDD, a multiple mobile sinks data dissemination mechanism for solving the dissemination problem. The main ideas of MSDD are constructing a two-tier grid structure by a designated sink, exploiting a hierarchical monitoring mechanism, and employing a global agent to track the sink locations in order to make the emergencies reported to the sinks immediately, In addition, MSDD supports the query-driven data dissemination. Being compared with TTDD, MSDD is theoretically proved to have less communication overhead. We also validate MSDD outperforms TTDD in reliability and the emergency delivery latency bv simulations.
文摘In the network environment, changes of resources structure, information technology and users requirements of standards library cause series of problems such as unobvious effect of services, low efficiency of resource utilization, poor innovation ability, etc. And we point out the problems and challenges faced by traditional standards library in the network environment. The standards library must redesign the organization structure and business process radically so that standards library could improve the service model, enhance the service quality and utilization rate of various document resources.
