覆盖网能有效分离网络应用与底层网络基础设施,提升服务质量(quality of service,QoS)和用户体验(quality of users’experience,QoE)。设计了一种普适性较强的覆盖网拓扑构建算法——基于最小生成树(minimum spanning tree,MST)的拓扑...覆盖网能有效分离网络应用与底层网络基础设施,提升服务质量(quality of service,QoS)和用户体验(quality of users’experience,QoE)。设计了一种普适性较强的覆盖网拓扑构建算法——基于最小生成树(minimum spanning tree,MST)的拓扑感知度约束(minimum spanning tree-based topology-aware degree bound,MST-TADB)覆盖网构建算法。该方法感知网络拓扑,逐步生成MST,同时参考节点的转发和计算能力作为节点度约束收敛算法。由仿真结果可知,和同类算法相比,本文方法的故障恢复率、恢复路径跳数惩罚、服务节点平均节点度和时间复杂度综合权衡较好,并保证了所构建的覆盖网的自愈性。展开更多
This paper presents an overlay network topology called Virtual and Dynamic Hierarchical Architecture (VDHA) for discovering Grid services with high performance. Service discovery based on VDHA has scalable, autonomous...This paper presents an overlay network topology called Virtual and Dynamic Hierarchical Architecture (VDHA) for discovering Grid services with high performance. Service discovery based on VDHA has scalable, autonomous, efficient, reliable and quick responsive. We propose two service discovery algorithms. Full Search Query and Discovery Protocol (FSQDP) discovers the nodes that match the request message from all N nodes, which has time complexity O(logN), space complexity O(nvg) (nvg being node numbers of each virtual group), and message-cost O(N), and Domain-Specific Query and Discovery Protocol (DSQDP) searches nodes in only specific domains with time complexity O(nvg), space complexity O(nvg), and message-cost O(nvg). In this paper, we also describe VDHA, its formal definition, and Grid Group Management Protocol.展开更多
In this paper, we propose the dynamically-evolving active overlay network （DEAON）, which is an efficient, scalable yet simple protocol to facilitate applications of decentralized information retrieval in P2P network...In this paper, we propose the dynamically-evolving active overlay network （DEAON）, which is an efficient, scalable yet simple protocol to facilitate applications of decentralized information retrieval in P2P networks. DEAON consists of three novel components ： a Desirable Topology Construction and Adaptation algorithm to guide the evolution of the overlay topology towards a small-world-like graph; a Semantic-based Neighbor Selection scheme to conduct an online neighbor ranking; a Topology-aware Intelligent Search mechanism to forward incoming queries to deliberately selected neighbors. We deploy and compare DEAON with other several existing distributed search techniques over static and dynamic environments. The results indicate that DEAON outperforms its competitors by achieving higher recall rate while using much less network resources, in both of the above environments.展开更多
The author constructs the sheaf of generalized fundamental group of a topological space Xand obtains the relationship between its lst cohomology set and all covering spaces Of X undersuitable conditions imposed upon X.
文摘This paper presents an overlay network topology called Virtual and Dynamic Hierarchical Architecture (VDHA) for discovering Grid services with high performance. Service discovery based on VDHA has scalable, autonomous, efficient, reliable and quick responsive. We propose two service discovery algorithms. Full Search Query and Discovery Protocol (FSQDP) discovers the nodes that match the request message from all N nodes, which has time complexity O(logN), space complexity O(nvg) (nvg being node numbers of each virtual group), and message-cost O(N), and Domain-Specific Query and Discovery Protocol (DSQDP) searches nodes in only specific domains with time complexity O(nvg), space complexity O(nvg), and message-cost O(nvg). In this paper, we also describe VDHA, its formal definition, and Grid Group Management Protocol.
文摘In this paper, we propose the dynamically-evolving active overlay network （DEAON）, which is an efficient, scalable yet simple protocol to facilitate applications of decentralized information retrieval in P2P networks. DEAON consists of three novel components ： a Desirable Topology Construction and Adaptation algorithm to guide the evolution of the overlay topology towards a small-world-like graph; a Semantic-based Neighbor Selection scheme to conduct an online neighbor ranking; a Topology-aware Intelligent Search mechanism to forward incoming queries to deliberately selected neighbors. We deploy and compare DEAON with other several existing distributed search techniques over static and dynamic environments. The results indicate that DEAON outperforms its competitors by achieving higher recall rate while using much less network resources, in both of the above environments.
文摘The author constructs the sheaf of generalized fundamental group of a topological space Xand obtains the relationship between its lst cohomology set and all covering spaces Of X undersuitable conditions imposed upon X.
