共查询到20条相似文献,搜索用时 140 毫秒
1.
2.
本文讨论高可靠性并行处理群机系统的通信互连网络及切换技术。首先介绍存储器通道,然后研究基于该结构的一个四处理结点的高可靠性并行处理群机系统,并对通信及系统切换性能进行了分析。 相似文献
3.
近年来随着空间网络应用的快速发展,临近空间网络逐渐成为新的研究热点。高度暴露、动态组网、通信能力受限的临近空间网络要求高实时性、高安全性移动安全接入,具有频繁的入/退网、频繁切换的特点,对切换效率与安全提出了更高的要求。提出了一种临近空间网络安全切换机制,给出了安全切换的定义、内涵,分析了安全切换与传统切换、切换安全的不同之处,并设计了MPHR选择算法与信任传递机制,实现了安全通道的整体切换与安全通信的连续性,在保证安全性的同时有效提高了切换效率,减少了临近空间网络的安全切换延时。 相似文献
4.
5.
本文讨论了高可靠性并行处理群体系统的通信互连网络及切换技术。首先介绍存储器通道,然后研究了基于该结构的一个四处理结点的高可靠性并行处理群机系统,并对通信及系统切换性能进行了分析。 相似文献
6.
对断电后业务保护问题进行分析,通道保护和复用段保护是传输网常用的保护方式,由于网络容量不同、保护机制不同,在网络保护方式选择上要依据实际情况来定。在经常停电的站点要选择通道环或用光切换设备来保护网上其它站点的业务;但由于通道环的容量相对小,核心层和汇聚层网络不适合使用通道环。所以核心层和汇聚层一般使用复用段保护或ASON网络,这就要求核心层、汇聚层节点的配套设施与之匹配,避免由于停电,而影响业务。 相似文献
7.
8.
王健 《计算机测量与控制》2010,18(1)
多波束天线利用多信号分类(MUSIC)算法对目标参数进行精确估计时,存在多波束天线的通道幅度和相位误差的失配现象,使MUSIC算法的性能严重下降;针对基于MUSIC的数字波束通道不一致问题,给出了一种新的基于MUSIC算法的最小化代价函数的波束无源自校正算法,利用阵列结构的先验知识对接收数据进行预处理,得到校正矩阵后自校正,并根据多波束阵列天线形成网络天线实测参数,加入随机幅度和相位误差进行计算机模拟仿真,验证仿真算法的正确性。 相似文献
9.
10.
11.
Pan Li Scalabrino N. Yuguang Fang Gregori E. Chlamtac I. 《Parallel and Distributed Systems, IEEE Transactions on》2009,20(11):1641-1652
Operating on a frequency band occupying several nonoverlapping channels, IEEE 802.11 is now widely used in wireless mesh networks (WMNs). Many multichannel MAC protocols are proposed to improve the spatial reuse in the network under the assumption that the transmissions on nonoverlapping channels do not interfere with each other. Some joint routing and channel assignment algorithms are also designed to increase the network throughput based on the premise that we can switch between different channels freely. Although simulations show that great improvements on network throughput can be observed in both cases, two fundamental questions remain: 1) Can we really use multiple nonoverlapping channels freely in WMNs? 2) If we can, what will be the cost when we switch channels dynamically and frequently? In this paper, by conducting extensive experiments on our testbed, we attempt to answer these questions. We find that in spite of interference between both overlapping and nonoverlapping channels, we can still use multiple channels in mesh networks under certain conditions but with care. We also show that the channel switching cost is actually very significant in WMNs. We recommend not to switch the channels too frequently when designing the channel assignment algorithms, and those channel assignment algorithms selecting one channel for each packet are not really beneficial. 相似文献
12.
The performance analysis of packet switched networks usually does not account for the loss of transmission bandwidth caused by the switch processing time. In wide area networks, where transmission channels are of the order of 64 kbps or less, this is a valid approach since switch processing time is negligible compared to average transmission times for packets. However, in Local Area Networks (LANs), the transmission channels are usually of the order of 1 mbps or greater and thus when evaluating the performance of a LAN that is based on a packet switch, it is necessary to consider the effect of the switch processing time which is now comparable to that of the average packet's transmission time. This paper investigates the effect of this processing time on network performance, and an exhaustive cyclic queueing algorithm to minimise this effect on overall network performance is discussed. An approximate analytical technique for evaluating the performance of such a LAN is derived. This technique makes it possible to do interactive calculations which can be used in the provisioning and configuring of such networks. 相似文献
13.
三层交换机既实现数据的高速交换,又完成VLAN之间的路由.在网络规划设计时,利用两台互为备份设备第三层路由模块的连接和第二层交换模块的连接的结合来达到冗余备份、提高网络可靠性的功能.本文详细阐述了三层交换机进行VRRp冗余备份时所采用的两种方式. 相似文献
14.
叶刚 《计算机光盘软件与应用》2011,(21)
三层交换机是将交换机融入到网络层功能中,并实现与第二层交换机、第三层路由器的有机结合。发挥各自优势。通过应用三层交换机,可有效提高网络运行的稳定性与安全性。本文结合笔者实际经验。对局域网组网中接入层开始使用三层交换机的必要性等相关问题进行分析与阐述。 相似文献
15.
16.
We present a practical scheme for deterministically teleporting quantum information via probabilistic communication channels in a centralized quantum switch network. In the network, a central quantum switch agent is assigned for regulating probabilistic channels so as to construct a direct deterministic channel between the sender and the receiver. This scheme is further extended to a hierarchical network and a tree network involving multiple agents. The advantage of the scheme is that all required multi qubit gates from distributed terminal agents are uniformly performed by a central agent, with which the physical design of terminal nodes is greatly simplified and more reliable deterministic teleportation can be realized in a centralized quantum probabilistic network. 相似文献
17.
认知无线电思想在ZigBee无线传感器网络中的应用 总被引:1,自引:0,他引:1
本文将认知无线电的思想在基于ZigBee技术的无线传感器网络中进行应用尝试,提出一种新的多频多跳的Ad-hoc组网方法。该方法充分利用现代高级无线射频芯片对信道占用情况的能量检测功能,解决了传统网络采用时分复用的方法时对信道的利用率不高的问题。针对该方法只在组网开始时对信道进行静态频谱分配的不足,本文给出了进一步改进的建议。改进后的算法具有依据射频情况智能地判决是否进行信道切换的功能。 相似文献
18.
Linux操作系统实时性测试及分析 总被引:2,自引:0,他引:2
在特定平台上对Linux的实时性重要指标:中断响应和上下文切换开销加以测试并分析,为Linux嵌入式中的实时应用提供了依据。Linux中断响应与Linux内核机制和内存管理机制紧密相关,而Linux上下文切换开销与Linux进程空间和硬件平台情况紧密相关。 相似文献
19.
弹性分组环(ResilientPacketRing,RPR)是一种能高效地支持数据业务的新兴城域网络技术。论文主要使用IntelIXP2800网络处理器设计和实现了能为以太网提供接入RPR网络能力的三层交换机。设计过程中,在二层交换机制的基础上,参考了IPoverRPR框架和三层交换原理,对RPR网络与以太网络之间IP数据交换机制进行了优化,并借助IXP2800网络处理器的高性能和灵活性,使该交换机能高效地进行IP数据交换,而且提高了RPR环网的带宽利用率。 相似文献
20.
本文通过对二层交换机、三层交换机工作原理的分析,从网络拓扑结构、网络带宽、网络优化三个方面探讨了构建三层交换以太网的设计。 相似文献