基于路径标识的多路径域间路由的开发与实现

针对现有网络架构中路由扩展性方面的问题日益严重,目前提出一种基于路径标识的多路径域间路由方案,可提高域间路由可扩展性和可靠性,但该研究只停留在理论阶段。现对基于路径标识的多路径路由协议进行了开发与实现,针对域间路由协议BGP的控制层和基于Linux内核的转发层进行了具体模块的结构分析和开发,并进行了功能性测试。结果显示,开发系统可以实现路径标识路由和多路径路由的功能。     

一种Ad Hoc网络中路由软切换策略的研究

提出了一种新的Ad Hoc网络中对路由的维护方法,即基于局部多路径路由维护的路由软切换技术。在当前路由中某段或某几段链路出现问题时,通过建立局部的多路径路由,分担问题链路中的负载,维护网络保持通信连接不被中断;当路由稳定时,从局部多路径路由中寻找一条满足当前主路由通信需要的子路径,并且将数据传输切换到此子路径上,达到路由抢先维护和软切换的目的。该方法能够缩短路由重建的时间,延长单路径路由的寿命,使用多路径维护,避免了网络拥塞出现造成路由中断,能够很好地提高网络性能。     

Ad Hoc网络基于能源熵的多路径安全路由协议

由于节点是随机移动的,且其电池容量有限,在无线Ad Hoc网络(自组织网络)中减少能源消耗以延长网络生存期、保证节点的安全性是研究多路径路由中的主要问题。文章分析了AODV(基于距离矢量单路径按需路由)协议和AOMDV(基于距离矢量多路径按需路由)协议的一些基本特点,在考虑安全网格定位服务的基础上,结合能源熵,提出了一种新的安全多路径路由协议-EEBSMRP。仿真计算结果表明,EEBSMRP在发现最小的节点能源消耗路由、平衡各个节点能源利用率、延长整个网络生存期以及安全性方面有较大的改进。     

基于Ad Hoc的多路径路由协议研究

分析Ad Hoc网络中单路径路由协议和多路径路由协议的特点,指出当前Ad Hoc网络中多路径路由协议的研究进展。对当前已有的几种典型多路径路由协议进行介绍分析,得出在多路径路由协议设计时所面临的各种问题,为今进一步研究基于Ad Hoc的多路径路由协议提供重要参考。     

移动Ad hoc网络多路径路由技术研究

相对于单路径路由而言,多路径路由在容错、路由可靠性、QoS路由等方面有很多优势。因此,为了进一步提高移动Ad Hoc网络的路由质量,多路径路由问题逐渐成为了近年来的一个研究热点。首先在分析传统的单路径路由协议的特点和不足的基础上,阐述了多路径路由的基本概念及其分类,以及多路径路由的优势。然后介绍了移动Ad hoc网络中多路径路由技术的最新研究进展,并对有关多径路由协议进行了评述。     

面向Ad Hoc网络的多路径路由协议研究

Ad Hoc网络多路径路由协议作为对单路径的扩展,具备提供容错、负载平衡和更多的聚合带宽等优点。本文在研究了一种典型路由协议的基础上,提出了一种基于变化能量的多路径路由协议算法。仿真实验表明,该改进算法相对于AODV协议在时间延迟和成功投包率上都得到了较大的提高。     

QoS路由的多路径算法

本文分析了预约网络中采用多路径路由传送数据以保证应用的带宽要求、和/或端到端时延限制条件.文中提出的路由方案综合了单路径和多路径路由的优点:通过多路径路由以降低呼叫阻塞率,同时侧重单路径路由以降低协议开销.在考察网络中的四个一般性问题基础上,提出了启发式算法.     

基于AOMDV的多径路由协议改进及仿真分析

Ad Hoc网络是由一些移动节点组成、拓扑结构复杂且动态变化的自组织网络。网络中没有固定的网络基础设施,对路由协议要求较高。通过在每个节点的路由表和发送接收包中增加能量参数等措施,提出基于AOMDV的多路径路由协议改进方案PE-AOMDV协议,最后在NS2仿真平台上实现对改进的AOMDV多路径路由协议仿真分析。仿真结果表明：与AOMDV协议相比,新的基于能量的多路径路由协议PE-AOMDV的传输时延和路由开销都有所降低,并提高了分组投递率,从而提高了网络性能。     

移动Ad Hoc网络中基于Qos的多路径路由协议研究

针对现有移动Ad Hoc网在大流量业务下无法提供高质量QoS保障的问题,通过推导证明提出了路径长度限制的路径稳定的约束关系,进而将QoS的判定因子引入一种确定性的最优权值约束路由算法进行实例化,并在该路由算法的基础上提出了基于QoS保障的多路径路由协议(MP-QAODV).通过仿真,验证了MP-QAODV协议在平均端到端时延、端到端数据分组投递率、归一化路由开销等方面优于AODV和AOMDV协议.     

基于树路由的ZigBee网络高效多径路由算法

针对ZigBee网络多路径分层树路由算法(Z-MHTR)存在网络开销过大,路径建立机制不够优化等问题,提出一种基于树路由的高效多路径路由算法Z-EMR(ZigBee Efficient Multipath Routing).Z-EMR算法在多路径建立过程中减少了寻路数据分组的发送个数,并且删除了树路径的重复发现过程,从而使得算法变得更加高效.仿真结果表明,与Z-MHTR算法相比,Z-EMR算法有效地降低了网络开销,减少了路径平均长度和平均端到端时延,达到了路径优化和提高ZigBee网络整体性能的目的.     

一种基于仿生学的MANET拥塞节点自适应回避路由协议

 针对MANET中出现的因节点拥塞而导致路由不稳定、频繁重路由等问题,本文借鉴大肠杆菌培育过程中对营养液浓度变化的新陈代谢自适应调节行为和其数学描述模型ARAS,提出了一种新的拥塞节点自适应回避的MANET路由协议ATAR,其主要思路是:将节点缓存队列信息(可反映该节点拥塞程度)和目的端反馈包跳数信息(可反映该节点到目的端的路径长短)归一化处理后定义为节点的适应值,并将其映射为菌体的成长速率;再在随机性上修正了原始描述模型ARAS,并用其分别计算该节点的所有邻节点若被当作它到目的端路由的下一跳节点时,它们各自对该路由性能的改善度,然后选择其中改善度最大的邻节点作为其下一跳节点,以自适应避开拥塞的邻节点,同时选择较短路径.仿真结果比较显示:ATAR突发大时延发生概率明显较小,具有更低的数据包平均端到端延迟,数据分组投递率也得到提高,体现出ATAR拥塞避免的策略优势较大,并且还观察到ATAR负载均衡程度也优于AODV,瓶颈节点承担的负载差异较AODV小54%.     

A bio‐inspired OSPF path selection scheme based on an adaptive attractor selection model

Current Internet Protocol routers only support equal cost multi‐path routing, which performs the random path selection or the traffic uniform distribution among equal‐cost paths. In biology, an adaptive attractor selection model is presented to simulate the concentration changes of two kinds of Escherichia coli 's mRNA in changing nutrition environments with bistability equations. Inspired by the metabolism behaviors of E. coli , we propose an adaptive path selection scheme Open Shortest Path First‐path selection by attractor selection to dynamically select the transmission path by the real‐time path quality. Here, the mRNA concentration is analogous to the path quality. Then, to reflect the multipath quality, multi‐stability equations are adopted and redesigned. Our scheme consists of two main features. The first one is a redefined path‐activity to indicate multipath transmission goodness, which is inversely proportional to the offset between current path quality and best path quality. And the second one is a new attractor expression of the multi‐stability equations to concretely specify the effect of a stochastic item noise in the equations on the path selection. Compared with the greedy selection and the uniform random selection in file transfer protocol (FTP) service, our scheme gains better performance on reducing file transmission time, traffic throughput, and traffic dropped. Copyright © 2015 John Wiley & Sons, Ltd.     

P-Chord:一种基于分区的Chord路由模型

在P2P系统中,有效地定位分布在网络中不同节点的数据资源一直是研究的重点。结构化P2P网络Chord的路由表存在着严重的信息冗余,影响了整个系统的效率。针对这种情况,文中在Chord的基础上提出了一种基于分区的Chord路由模型(P-Chord),通过对Chord的分区,将节点的路由表进行改造,消除了冗余信息,增加了有效信息。试验结果表明,P-Chord在保持Chord其他性能的前提下,减少了平均查找跳数,提高了查找效率。     

Novel disjoint path selection scheme based on link availability in ASON

Risk-disjoint routing is an efficient way to improve network survivability.In this article, a partial risk-disjoint routing algorithm based on link availability (PRDRA-LA) is proposed based on the complete risk-disjoint routing algorithm (CRDRA).While calculating the protection path with PRDRA-LA, the links that share risks with the links in the working path are filtered by link availability.In addition, the risk disjoint degree between the protection path and the working path can be adjusted freely.Simulation results showed that when compared with CRDRA, routing connections with PRDRA-LA can achieve improved survivability while the number of connections that can be successfully routed over the current network is kept from serious decline.     

一种归一化QPLL的未知时变谐波噪声主动控制算法

针对船舶机械未知时变谐波噪声的主动控制问题,基于正交锁相环原理,提出了一种归一化QPLL（Quadrature Phase Locked Loop）的未知时变谐波噪声主动控制方法.通过在相位/频率更新结构中引入参数调整因子,形成一种改进的QPLL结构;引入次级通道,设计并提出了基于QPLL的未知时变谐波噪声控制算法.首先,通过平均化理论和线性化方法,分析该算法的稳定性,指出了次级通道特性和谐波信号幅值对该算法收敛性能的影响;其次,基于分析结果,引入次级通道、幅值归一化措施,形成一种归一化的未知时变谐波噪声主动控制算法,提升稳定性能和收敛速度;最后,通过仿真验证了归一化改进措施对未知时变谐波噪声主动控制算法综合性能的改善效果.     

移动Ad hoc网络基于链路可用时间的动态源路由协议

为了提高链路的稳定性,增加路径可用时间,提出一种应用于移动Ad hoc网络的基于链路可用时间的动态源路由协议(LARP).该协议以路径可用时间作为路径评价的参数,优先选择具有最大路径可用时间的路径进行数据包传递.路径可用时间反映了当前节点移动对路径稳定性的影响,其数值取决于路径中的最小链路可用时间.仿真结果表明该协议相...     

A RWA Algorithm for Differentiated Services with QoS Guarantees in the Next Generation Internet based on DWDM Networks

A major challenge in next generation Internet (NGI) backbone networks based on dense-wavelength division multiplexing (DWDM) is the provision of guaranteed quality-of-service (QoS) for a wide variety of multimedia applications. This paper proposes a new routing algorithm called multi-wavelength minimum interference path routing (MW-MIPR) to provide more reliable QoS guarantees by consideration of the potential future network's congestion status. This improves wavelength utilization by choosing a route that does not interfere too much with potential future connection requests. Moreover, we introduce a differentiated routing and wavelength assignment (RWA) mechanism combined with recovery strategy and the proposed MW-MIPR algorithm based on the differentiated service model in the NGI. Simulation results show that the proposed MW-MIPR algorithm achieves a smaller blocking probability than dynamic routing (DR) that yields the best performance among previous RWA algorithms. And we prove that a differentiated RWA combined with a recovery capability together with the proposed routing scheme provides satisfied QoS assurance for each service class in terms of signal quality and survivability.     

Routing metric of interference-aware link quality： an improved ETX in wireless mesh networks

This article addresses the problem of route selection in wireless mesh networks （WMNs）. The traditional routing metrics adopt packet delivery ratio （PDR） as a representative metric of wireless link quality assessment. However, PDR measured by the broadcast-based probe method is affected by the size, number and transmission rate of probe packets, which influences the metric accuracy. In this paper, improved expected transmission count （iETX）, a new routing metric of interference-aware link quality, is proposed for WMNs. Dispensing with traditional broadcast-based probing method, the iETX uses regional physical interference model to obtain PDR. Regional physical interference model is built upon the relationship between signal to interference plus noise ratio （SINR） and PDR, which contributes to the improvement of metric accuracy. The iETX comprehensively considers the effects of interference and link quality and minimizes the expected number of packet transmissions required for successful delivery, which helps find a path with minimum interference and high throughput. Simulation shows that the proposed metric can significantly improve the network performance.     

层次分析法在ZigBee网络语音通信中的应用研究

在自组织网络语音通信中,针对音频传输中存在的延时、丢包等主要问题,在ZigBee网络路由的基础上建立层次分析法评价模型,设计了一种音频传输路由算法AHP-RP。通过分析路径链路质量、音频负载值、路径存活时间和路径长度等因素对音频质量的影响,构建以网络的4个因素为因子的比较矩阵,选择最优传输路径。仿真及实际通信平台验证表明,该算法能有效地适应网络状态,明显改善了语音通话质量。     

FWM aware evolutionary programming algorithm for transparent optical networks

This paper proposes and evaluates a four-wave mixing (FWM) aware evolutionary programming algorithm for dynamically setting up lightpaths in an optical wavelength division multiplexed network (WDM network). The proposed algorithm also considers the effect of amplified spontaneous emission noise (ASE noise) on a lightpath during propagation of the optical signal from any source to the intended destination. As crosstalk due to FWM and ASE noise are two transmission impairments that degrade the quality of optical signal even at low to medium data rates, it is mandatory for an algorithm for dynamic routing and wavelength assignment in a WDM network to consider the effect of these two impairments on the lightpath to be established. The distinguishing feature of the proposed algorithm is that it is based on an initial population of a single individual and uses a fitness function that is expressed in terms of the number of hops, path cost, variance contributions due to FWM crosstalk, amplifier noise, and different beat noises at the receiver. The performance of a newly introduced FWM aware priority-based wavelength assignment technique is compared with few of the existing wavelength assignment techniques in the present work.