光突发交换网络中QoS机制研究与实现

光突发交换作为下一代光互联网最有前途的解决方案已经越来越受到人们的关注,如何增强光突发交换网络的服务质量(QoS)保障能力,已成为光交换领域内的一个重要研究课题。论文对光突发交换网络中基于偏置时间的QoS机制进行了研究,采用低优先级直接丢弃算法,结合突发分片技术和最近可用信道-空隙填充算法,提出了一种新的QoS解决方案,通过建立相应的光突发交换网络模型对该解决方案进行了仿真比较,仿真结果表明该方案可以明显地降低阻塞率,提高信道利用率,为各类业务提供良好的QoS保障。     

Circuit-Switched Broadcasting in Multi-Port Multi-Dimensional Torus Networks

The one-to-all broadcast is the most primary collective communication pattern in a multicomputer network. This paper studies this problem in a circuit-switched torus with -port capability, where a node can simultaneously send and receive messages at one time. This is a generalization of the one-port and all-port models. We show how to efficiently perform broadcast in tori of any dimension, any size, square or nonsquare, using near optimal numbers of steps. The main techniques used are: (i) a span-by-dimension approach, which makes our solution scalable to torus dimensions, and (ii) a squeeze-then-expand approach, which makes possible solving the difficult cases where tori are non-square. Existing results, as compared to ours, can only solve very restricted sizes or dimensions of tori, or use more numbers of steps.     

A Sampler of Circuit Switching Networks

This overview presents several different types of circuit switching networks: concentrators, connectors, expanders, partitioners, SIMD interconnectors, and sorters.     

基于应用的交换网络

随着网络应用的多样化,计算机网络不仅要提供足够的带宽,而且对于不同的应用要具有不同的服务质量(QoS)。该文通过对多层交换的介绍,说明了在多层交换技术支持下,如何保证不同网络应用的QoS,以满足用户网络应用的需求。     

一种交换式网络内的ARP欺骗的解决方案

研究了ARP欺骗的原理，给出了一种网络级检测和恢复变换式局域网内ARP欺骗的解决方案．并使用基于WinPcap开发的测试程序进行了实现并在局域网内进行了测试。实验表明该方案能够成功检测该局域网内存在的ARP欺骗。并能成功地恢复。     

A Comparative Study of Switching Methods in Multicomputer Networks

The switching method determines the way messages visit intermediate routers, and has a great impact on network performance. This paper conducts an extensive comparative performance analysis, by means of analytical modelling, of three well-known switching methods proposed for multicomputer networks, namely wormhole switching, circuit switching, and pipelined circuit switching. The results reveal that wormhole switching is the most efficient when messages are short. Pipelined circuit switching can perform better than circuit switching and provides superior performance over wormhole switching when messages are relatively long.     

一种适应于移动互连网的数字签名方案

本文描述了一种适用于移动互连网的数字签名方案。这种方案基于分布式计算体系,在签名者(或验证签名者)私有密钥和与通信对端共享的密钥不扩散的前提下实现签名方案。该方案解决了在只有弱计算能力的移动通信终端进行复杂签名和验证签名计算的问题。     

Flocking in Fixed and Switching Networks

This note analyzes the stability properties of a group of mobile agents that align their velocity vectors, and stabilize their inter-agent distances, using decentralized, nearest-neighbor interaction rules, exchanging information over networks that change arbitrarily (no dwell time between consecutive switches). These changes introduce discontinuities in the agent control laws. To accommodate for arbitrary switching in the topology of the network of agent interactions we employ nonsmooth analysis. The main result is that regardless of switching, convergence to a common velocity vector and stabilization of inter-agent distances is still guaranteed as long as the network remains connected at all times     

绿色网络节能方案综述

随着互联网的迅速发展、移动通信的广泛普及，信息通讯技术（Information and Communication Technology，ICT）发挥着越来越重要的作用。与此同时，网络能源的消耗也急剧攀升。为了应对业务量的增长，无法预测的实时流量，以及保证连接和服务质量（Quality of Service，QoS），现有网络通常是按照网络业务量的峰值来设定，而且网络设备的耗能有时也是按照峰值来设定。但是网络的业务量在大部分时间里不会达到峰值，甚至远远小于峰值。这就意味着能量的利用率很低，大部分的能量会被浪费掉。因此，降低能耗成本，提高能耗利用率已经成为目前急需解决的问题。这一类问题被统称为绿色网络节能问题。针对目前已有的绿色网络节能方案，将这些方案根据在不同网络中的节能问题分成了三类，并对不同分类中的具体方案进行详细描述，对比了它们之间的优缺点，总结分析了这些方案的贡献及不足，并进一步提出了未来的研究方向。     

一种高速网络的公平带宽算法

路由器的设计要考虑带宽的公平分配问题。就象公平排队算法(FairQueueing)所做的一样,它有许多对互联网上拥塞控制的考虑。然而,这样的要求经常需要设置一些状态、控制缓存块、和/或在考虑每个信息流基础上的复杂的数据包处理算法。技术的复杂性使得它的应用和配置难以得到推广。为了降低设计复杂度,文章提出了一种新的体系结构及在其之上的算法。根据其特点,把这种算法称为状态无关的核心路由器公平排队算法(Core-StatelessFairQueueing)。