This paper presented a new shared cache technique-the grouping cache, which could solve many invalid queries in the broadcast probe and the control bottleneck of the centralized web cache by dividing all cooperative c...This paper presented a new shared cache technique-the grouping cache, which could solve many invalid queries in the broadcast probe and the control bottleneck of the centralized web cache by dividing all cooperative caches into several groups according to their positions in the network topology. The technique has the following characteristics: The overhead of multi-cache query can be reduced efficiently by the cache grouping scheme; the compact summary of the cache directory can rapidly determine if a request exists in a cache within the group; the distribution algorithm based on the web-access logs can effectively balance the load among all the groups. The simulation test demonstrated that the grouping cache was more effective than any other existing shared cache techniques.展开更多
Hybrid systems can be represented by a discrete event model interacting with a continuous model, and the interface by ideal switching components which modify the topology of a system at the switching time. This paper ...Hybrid systems can be represented by a discrete event model interacting with a continuous model, and the interface by ideal switching components which modify the topology of a system at the switching time. This paper deals with the modelling of such systems using the bond graph approach. The paper shows the interest of the implicit representation: to derive a unique state equation with jumping parameters, to derive the implicit state equation with index of nilpotency one corresponding to each configuration, to analyze the properties of those models and to compute the discontinuity.展开更多
The stable multicast flow aggregation （MFA） problem in internet protocol （IP） over optical network under the dynamical scenario is studied. Given an optical network topology, there is a set of head ends and access...The stable multicast flow aggregation （MFA） problem in internet protocol （IP） over optical network under the dynamical scenario is studied. Given an optical network topology, there is a set of head ends and access touters attached to the optical network, in which each head end can provide a set of programs （IP multicasting flows） and each access router requests a set of programs, we find a set of stable light-trees to accommodate the optimally aggregated multicast IP flows if the requests of access touters changed dynamically. We introduce a program correlation matrix to describe the preference of end users＇ requests. As the original MFA problem is NP-complete, a heuristic approach, named most correlated program first （MCPF）, is presented and compared with the extended least tree first （ELTF） algorithm which is topology- aware. Simulation results show that MCPF can achieve better performance than ELTF in terms of stability with negligible increment of network resource usage.展开更多
文摘This paper presented a new shared cache technique-the grouping cache, which could solve many invalid queries in the broadcast probe and the control bottleneck of the centralized web cache by dividing all cooperative caches into several groups according to their positions in the network topology. The technique has the following characteristics: The overhead of multi-cache query can be reduced efficiently by the cache grouping scheme; the compact summary of the cache directory can rapidly determine if a request exists in a cache within the group; the distribution algorithm based on the web-access logs can effectively balance the load among all the groups. The simulation test demonstrated that the grouping cache was more effective than any other existing shared cache techniques.
基金supported by the Taishan Scholar Construction Engineering by Shandong Government,the National Natural Science Foundation of China(61034007,61120106011,61203029,61304045,61403235)
文摘Hybrid systems can be represented by a discrete event model interacting with a continuous model, and the interface by ideal switching components which modify the topology of a system at the switching time. This paper deals with the modelling of such systems using the bond graph approach. The paper shows the interest of the implicit representation: to derive a unique state equation with jumping parameters, to derive the implicit state equation with index of nilpotency one corresponding to each configuration, to analyze the properties of those models and to compute the discontinuity.
基金the National Natural Science Foundation of China (No.60502004) and the"863"Program of China.
文摘The stable multicast flow aggregation （MFA） problem in internet protocol （IP） over optical network under the dynamical scenario is studied. Given an optical network topology, there is a set of head ends and access touters attached to the optical network, in which each head end can provide a set of programs （IP multicasting flows） and each access router requests a set of programs, we find a set of stable light-trees to accommodate the optimally aggregated multicast IP flows if the requests of access touters changed dynamically. We introduce a program correlation matrix to describe the preference of end users＇ requests. As the original MFA problem is NP-complete, a heuristic approach, named most correlated program first （MCPF）, is presented and compared with the extended least tree first （ELTF） algorithm which is topology- aware. Simulation results show that MCPF can achieve better performance than ELTF in terms of stability with negligible increment of network resource usage.
