共查询到20条相似文献,搜索用时 11 毫秒
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现在的虚拟机放置研究大多集中在物理服务器能源能耗或网络设备能耗的优化,然而随着这些资源的过度聚合,有可能会带来应用性能的下降。提出了一种虚拟机放置方案,主要有2个目的:最小化激活物理机和网络设备的个数来减少数据中心能源消耗;最小化最大链路利用率来改善网络性能。此方案在优化网络性能的同时,减少物理服务器和网络设备的能耗,使得能源效率与网络性能达到平衡。设计了一种新的二阶段启发式算法来求解,首先,利用基于最小割的层次聚类算法与最佳适应算法相结合来优化能源效率,然后,利用局部搜索算法再次优化虚拟机位置来最小化最大链路利用率。仿真实验结果表明,所提方案取得了良好的效果。 相似文献
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针对虚拟网的节能映射问题,建立了结合时间和能量感知的虚拟网映射算法。在对节点和路径的评价标准中加入了时间因素,综合考虑了物理资源的运行时间等因素,用概率理论辅助分析了每个虚拟节点的多个可用物理节点被选中的概率。在节点选择阶段,综合考虑底层节点的剩余资源量、CPU资源利用率增量、节点开启情况和是否延长使用时间等因素,并使用条件概率理论辅助分析得到各可用节点的重要性;在链路选择阶段,综合考虑链路开启情况、延长使用时间和链路长度等因素。不仅使虚拟网请求映射在当前较小的节点和链路集合中,而且映射到了延长时间较短的设备上。实验结果表明,与未考虑时间因素的方法相比,该方法能带来更好的性能和更低的能耗。 相似文献
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In order to deal with the performance degradation caused by resource contention due to the sharing of physical resources between VNF in the network slicing,a network slicing deployment method based on performance-awareness was proposed.When deploying network slice instances,first two-phase deployment that mapping virtual nodes was adopted,and then virtual links were mapped.In the virtual nodes mapping phase,the VNF performance influences factor was defined from the perspective of resource supply and demand to quantify the degree of VNF performance impact.Then the sum of the performance influence factors of all VNF on the deployable physical server was found in the network slice instance,the physical server with the smallest sum of performance influence factors was used as the mapping location,and the simulated annealing-discrete particle swarm algorithm was used to find the nodes mapping result.In the virtual links mapping phase,the shortest path algorithm was used to obtain the link mapping result.The simulation results show that the proposed method reduces the impact of other network slices on its own service performance. 相似文献
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在网络安全研究方面和网络运营商提供的服务中,虚拟机技术越来越起着重要位置.虚拟机的网络连接问题是首要解决的问题.在平时工作和研究中,人们对虚拟机网络连接概念模糊,相关的参数设置考虑不全,造成虚拟机找不到宿主机或宿主机找不到虚拟机,以至于虚拟机无法访问互联网.本文以虚拟机的三种网络连接模式为线索,论述不同连接模式下虚拟机与物理机在网络中的关系,以及虚拟机与宿主机的IP地址、子网掩码、网关和DNS服务器地址,阐明虚拟机网络连接参数设置方法. 相似文献
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Zhiguo Liu Lingyu Qin Qingli Liu Junmei Liu Yuanming Ding 《International Journal of Satellite Communications and Networking》2019,37(3):224-233
The virtual resource management architecture for satellite networks currently suffers from a very poor virtual network mapping success rate. This arises because of the need to map multiple heterogeneous virtual networks to the underlying satellite network. Most heuristic algorithms divide virtual network mapping into node mapping and link mapping, which aims to reduce the complexity of the problem. However, this approach is not well suited to highly dynamic satellite networks. In this paper, we propose a hybrid virtual network mapping algorithm that is based on threshold load. This takes the overall load for the nodes as its optimization objective, and combines the idea of backtracking contained in 1‐stage mapping methods and the idea of global optimization contained in 2‐stage mapping methods. The algorithm reduces the complexity of backtracking computation, while avoiding any incompleteness that might result from separating nodes and link mapping. The success rate for virtual network mapping is thus improved, as is the utilization rate for satellite network resources. 相似文献
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为对装备供应链可靠性进行评估,构建了一种基于贝叶斯网络的评估模型.首先,阐述了装备供应链可靠性的基本概念,然后,介绍了装备供应链的主要环节,最后,根据贝叶斯网络的基本原理,将装备供应链的故障树模型转化为贝叶斯网络模型. 相似文献
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基于动态贝叶斯网络的可信度量模型研究 总被引:1,自引:0,他引:1
针对可信网络中亟需解决的可信度量模型展开研究,以社会学中的人际关系信任模型为基础,研究网络节点间的可信关系,提出了一种与时间因素关联的基于动态贝叶斯网络的可信度量模型。该模型充分考虑身份认证、网络交互行为对可信度量的影响,引入历史交互证据窗口、时效性因子和惩罚因子,同时给出了直接可信度和间接可信度的聚合方法,提高了模型的动态自适应能力以及计算的灵敏度和准确度,有效地抑制了异常实体的威胁。仿真实验结果表明,与传统的贝叶斯网络模型相比,该模型能够灵敏有效地进行可信度计算,同时具有良好的动态自适应性。 相似文献
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针对目前传统入侵检测系统难以得出网络攻击行为之间存在的关联关系问题,以攻击图表示模型为指引,提出一种基于贝叶斯网络的攻击事件智能发掘模型。本文以先验知识建立贝叶斯攻击行为关联图。基于属性相似度聚合网络攻击行为,针对网络攻击场景设计高效的ExApriori算法发掘攻击行为间的关联规则,并建立攻击行为组集。利用贝叶斯攻击行为关联图的参数对攻击行为组集进行计算,实现对攻击事件的发掘。实验表明,本模型能有效提取网络攻击事件及发现攻击路径,为网络攻击事件的发现与应对措施提供理论支持和技术支撑。 相似文献
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Ching‐Huang Lin Chien‐Tung Lu Ying‐Hsien Chen Jung‐Shian Li 《International Journal of Communication Systems》2014,27(12):4210-4225
One of the key technologies in cloud computing is virtualization. Using virtualization, a system can optimize usage of resources, simplify management of infrastructure and software, and reduce hardware requirements. This research focuses on infrastructure as a service, resource allocation by providers for consumers, and explores the optimization of system utilization based on actual service traces of a real world cloud computing site. Before activating additional virtual machines (VM) for applications, the system examines CPU usage in the resource pools. The behavior of each VM can be estimated by monitoring the CPU usage for different types of services, and consequently, additional resources added or idle resources released. Based on historical observations of the required resources for each kind of service, the system can efficiently dispatch VMs. The proposed scheme can efficiently and effectively distribute resources to VMs for maximizing utilization of the cloud computing center. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Lü Bo HUANG Tao WANG Zhen-kai CHEN Jian-ya LIU Yun-jie LIU Jiang Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts Telecommunications Beijing China 《中国邮电高校学报(英文版)》2011,(5):87-94
Network virtualization is considered as a powerful way to deploy different network architectures and protocols over a shared physical infrastructure.Virtual network(VN)embedding plays an important role in the network virtualization environment.Virtual network embedding is mainly about mapping virtual nodes and virtual links onto the physical network resources efficiently.However,load balancing of substrate network has not received much consideration.This paper proposes an adaptive virtual network mapping algorithm based on status feedback.The main contribution is to embed the virtual network requests according to the current load distribution of substrate network.This adaptive algorithm differentiates the residual bandwidth of substrate links and takes full advantage of the multi-path to improve the load balancing of the substrate network.Simulation experiments show that the proposed algorithm improves the load distribution of substrate network distinctly while reducing the average substrate link stress significantly. 相似文献
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应用粒子群优化的绿色虚拟网络映射算法 总被引:1,自引:0,他引:1
绿色网络是近年来网络技术研究的热点,以节能为优化目标的虚拟网络映射算法成为基于网络虚拟化技术中资源分配研究的重点.提出了应用粒子群优化的绿色虚拟网络映射算法,重定义粒子群优化算法中的参数和粒子进化行为,以关闭底层网络节点和链路数量最多为适应度函数,在较低的算法复杂度条件下,获得绿色虚拟网络映射的最优解.仿真结果表明,与对比算法相比,静态环境下所提算法的运行时间大幅度降低;动态环境下所提算法的节点关闭率、链路关闭率、虚拟网络请求接受率均有所提升,算法运行时间也大大缩短. 相似文献
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针对无线网络链路可靠性差影响无线虚拟网络的分配这一问题,提出了一种基于链路可靠性的无线虚拟网络分配算法(WVNEA-LR)。该算法通过物理网络拓扑预处理和允许同一个虚拟请求中的多个虚拟节点映射到同一个物理节点上的方法,提高了Vn构建成功率和节约了物理链路资源。利用Q因子改善了因拓扑分配稀疏时Vn构建成功率低的问题。此外,WVNEA-LR的节点分配为链路分配作了准备,并通过选择可靠性高的承载路径保证了分配后的Vn具有高可靠性。仿真结果表明, WVNEA-LR获得较好的虚拟网络构建成功率、较高的收益成本比和资源利用率。 相似文献
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