Ad Hoc网络路由协议研究及其性能比较

介绍和分析了当前Ad Hoc网络中的主要路由协议算法,在Linux下使用网络仿真软件NS2评价Ad Hoc路由协议中的距离矢量路由协议、临时排序路由算法、动态源路由协议和Ad Hoc按需距离矢量路由协议,编写了用于仿真实现的脚本程序,并对仿真结果进行了分析比较和性能评价,由此得出不同协议的特性及其适用范围。     

移动代理技术在Ad Hoc无线网络中的应用研究

Ad Hoc无线网络是一组具有路由和转发功能的移动节点组成的一个多跳的临时性自治系统,是一种无中心的无线网络。现有的主动路由协议或者按需路由协议都不能很好地满足Ad Hoc网络的需要。介绍了Ad Hoc无线移动网络和移动代理技术。在分析了现有的2种路由协议后,提出了在按需路由协议中加入移动代理技术来增强Ad Hoc无线网络的性能。在这些结果的基础上,提出了移动代理通信协议。     

"线性结构"Ad Hoc网络按需路由协议的性能研究

"线性结构"的Ad Hoc网络有很多的实际应用.采用OPNET建立"线性结构"的Ad Hoc网络,对典型的按需路由协议DSR和AODV的接收分组数量、路由负载、信道接入时延、吞吐量等参数进行了仿真比较,为"线性结构"的Ad Hoc网络选择路由协议提供理论依据.     

AODV、AOMDV和AODV-UU路由协议性能仿真与分析

使用NS-2(Network Simulator Version 2)仿真软件,选取分组投递率、端到端平均时延、归一化路由开销和路由发现频率4个指标对按需距离矢量路由(AODV,Ad hoc On-Demand Distance Vector Routing)、多径按需距离矢量路由(AOMDV,Ad Hoc On-Demand Multipath Distance Vector Routing)和乌普萨拉大学开发的按需距离矢量路由(AODV-UU,Ad Hoc On-Demand Distance Vector Routing developed by Uppsala University)进行了性能仿真,通过改变节点最大运动速度和业务源连接对数分析比较这些参数对3个协议性能的影响,研究结果表明了AODV-UU协议的优越性。并提出了对AODV-UU协议的改进。     

紫外光空分复用自组织网络路由协议

为了改善紫外光(UV)点对点通信中传输距离有限、覆盖范围小的问题,组建了UV自组织(Ad Hoc)网络。结合UV通信的信道特性,提出了一种UV组网通信收发装置设计方案。基于该方案,给出了UV Ad Hoc网络节点定位算法,该算法利用节点间的通信距离和扇区信息求得节点间的相对位置。以无线Ad Hoc网络多播按需距离矢量路由协议为基础,提出了一种UV空分复用Ad Hoc网络路由协议,并对该路由协议进行了仿真,给出了不同节点数和运动区域下的仿真结果。结果表明:在满足发包数、时延和丢包率等通信要求的前提下,在一定运动区域内,应选择较少的节点;当节点数一定时,应选择较小的运动区域。     

Ad Hoc移动骨干网分层路由协议的研究

为了解决Ad Hoc网络的可扩充性问题,分级结构在Ad Hoc网络中的应用得到了广泛的研究.文中提出了一种适用于移动Ad Hoc网络中的多频分级结构--移动骨干网的分层路由协议Layered-AODV.该协议结合了网络多频分级的结构特点在各级采用不同的按需路由策略以降低全网冗余路由信息的传播,提高了网络的可扩展性.仿真结果表明,该协议能够有效减少移动Ad Hoc网络中的路由开销,端到端传播时延,并能有效地提高网络业务的性能,在一定程度上能够解决随着Ad Hoc网络规模扩大而网络性能下降的问题.     

移动Ad Hoc网络按需路由协议的研究

移动Ad Hoc网络是一种具有高度动态拓扑结构、节点任意移动的自组织网络。路由协议能够为数据分组的传输指定路径,是移动节点相互通信的基础,对移动Ad Hoc网络的性能起着至关重要的作用。文中介绍移动Ad Hoc网络及其路由协议的基本概念和特殊性,研究几种典型按需路由协议的原理,对协议进行综合比较,简要讨论了各自的优缺点。     

高动态Ad Hoc路由协议性能分析

Ad Hoc网络是一种没有固定设施的无线移动自组织网络,动态变化的拓扑结构对路由协议的性能有着重要影响。研究了动态源路由(DSR)协议、Ad Hoc按需距离矢量(AODV)路由协议和最优链路状态路由(OLSR)协议3种传统路由协议,利用OPNET软件作为仿真工具,设计了2种不同网络规模条件下空中飞行平台网络拓扑结构背景的高动态仿真方案,通过比较网络时延、归一化网络吞吐量、路由负载和数据传送成功率,分析了它们的性能。仿真结果表明,OLSR协议的综合性能优于其它协议,更适合于节点高速移动且网络拓扑结构频繁变化的Ad hoc网络,并为下一步研究打下基础。     

延长网络生存时间的AODV路由改进算法

AODV(Ad Hoc on-demand distance vector)路由协议是Ad Hoc网络中一种具有代表性的按需路由协议。传统的AODV是以“最小跳数”为参数建立和更新路由的。随着网络负荷的增加,以这种方式建立和更新路由容易引起网络中部分节点较其它节点更多地参与通信,在这些节点发生拥塞的可能性将更大,频率将更高,这会增加网络能耗,缩短网络生存时间。针对这一问题,笔者提出了通过控制拥塞对AODV进行节能改进的一种算法—Lengthen Lifetime AODV(LLAODV)。     

AODV路由协议性能的改进研究

路由问题一直是移动Ad Hoc网络（MANET）研究中的难点和重要问题。按需路由协议是当前移动Ad Hoc网络的主流路由协议。丈中通过对AODV和DSR两种典型的按需路由协议的分析与比较，提出了一种利用DSR的路径收集机制来改进和提高AODV路由协议性能的方法。通过NS2仿真实验表明，该方法能有效减少路由请求的数量，从而降低路由的开销，提高分组发送的成功率，减少端对端的延时。     

Middleman covert channel establishment based on MORE routing protocol using network coding in ad hoc networks

Covert channels have been recently the subject of the study in both creation and countermeasure aspects. There are many different ways to embed the covert data in network standards and protocols, especially in wireless networks. MORE (MAC‐independent opportunistic routing) is an opportunistic routing protocol which uses networks coding to enhance routing performance by reducing the repetitions. This protocol can be a suitable medium for covert channel establishment. A middleman covert channel establishment method is proposed in this paper over MORE routing protocol and with the use of network coding. Hidden data are transferred through packet's payload bytes. Covert sender manipulates coding mechanism by calculating packets' coefficients instead of random selection. The proposed covert channel provides the average throughput of 218 and 231 bps, using two different data length approaches which is relatively a good comparing to the previous network layer covert channels. The proposed covert channel is also a covert storage channel and cannot be removed or restricted. Effect of different network characteristics on the proposed method's capacity and security is investigated by a simulation study, and the results are discussed.     

Dynamic Adaptive Routing for a Heterogeneous Wireless Network

This paper presents an integrated architecture of a Heterogeneous Wireless Network (HWN) and a dynamic adaptive routing protocol (DARP) for a HWN. To allow mobile users versatile communication with anyone or any device at any place and anytime, HWN integrates cellular network with an ad hoc network (independent Basic Service Set) in wireless local area network (WLAN) and reserves advantages of sizable coverage in a cellular network and high data rate in deployable ad hoc network. It also enlarges the scope of communication for ad hoc network and improves the throughput for cellular network. Consequently, nodes in HWN can communicate with each other or access Internet ubiquitously. We also address the routing issues for HWN, because the routing protocol for HWN is different from those used in cellular network or ad hoc network. The dynamic adaptive routing protocol establishes a better path for the source to arrive at the destination across multiple hops or cellular network and provides appropriate QoS (quality of service) in HWN.Through simulation, we will demonstrate the merit of the HWN, proposed routing performance on HWN and overhead of control traffic. A performance analysis of the proposed protocol is depicted. The results of the analysis, and simulations, are presented and discussed.     

基于节能的移动Ad Hoc网络AODV路由协议改进

移动Ad Hoc网络是一种无基础设施的新型无线网络.由于军事和抢险救灾等方面的需要,移动Ad Hoc网络路由协议成为当前研究的热点之一.在AODV协议的基础上,提出了一种节能的路由协9义AODVE,并采用了备份路由机制.仿真结果验证了,相对于AODV,该协议在分组传输率、时延和路由开销方面得到了较大的改善.     

基于LEACH的WSN路由算法研究

为了提高无线传感器网络的可扩展性在其路由协议中通常会采用分簇技术。由于无线传感器网络由能量有限的节点组成,网络中节点的能量多为电池供电,因此高效节能以延长网络生命周期是无线传感器网络必须要充分考虑的问题。针对LEACH(低功耗自适应分簇)路由算法在簇首选择时存在的问题,提出一种改进建议。对改进算法利用仿真工具NS2进行仿真,并对节点存活率和网络能耗两个方面进行比较与分析,仿真结果表明,改进算法很好地延长了网络的寿命。     

Adaptive load distribution approach based on congestion control scheme in ad-hoc networks

The ‘load distribution’ proposition in mobile ad-hoc networks (MANETs) is accomplishing great stimulation. This is because of the phenomenal facets it possesses including advanced network resilience, reliability and performance. Though there are other leading network layer routing protocols, but they radically utilise single-path communication paradigm, which is why they fail in achieving efficient load distribution in a network. Via this paper, we propose an efficient cross-layer adaptive load distribution approach to capitalise network’s channel utilisation and to rapidly adapt to dynamic wireless channel characteristic changes. The proposed method modifies the load balanced congestion adaptive routing (LBCAR) protocol and is developed using dynamic load distribution technique, by pioneering (i) novel parameters, which report for the availability of route pertaining to minimum traffic load and better link lifetime and also adapt according to varying available network resources; (ii) an absolute dynamic method to lessen the redundant route oscillations which further reduces the routing instabilities. The simulation results demonstrate the usefulness of the proposed method and yields better results in comparison to LBCAR and standard instead of dynamic ource outing, it is dynamic source routing (DSR) protocol.     

认知无线Mesh网络中满足QoS的高吞吐量安全路由协议

提出了一种综合考虑链路安全、链路冲突、链路可靠度与链路可用带宽的路由判据SIEB。SIEB包括链路安全和链路性能2个方面,在SIEB的链路安全权值计算中,为了抵御各种洞攻击,提出了基于两跳邻居反馈的链路信任值计算方法。在此基础上,提出了链路安全权值计算算法LSWC和链路性能权值计算算法LSPC,提出了分布式满足QoS约束的路由协议SIEBP,SIEBP的目标是：构造安全的路由路径,并且最大化网络吞吐量。仿真结果表明,SIEBP能达到预定目标,构造的路径能抵御黑洞、灰洞、虫洞等攻击,并且获得了较高的网络吞吐量。     

基于AODV的多度量无线路由算法研究

随着移动自组网络的快速发展,对距离矢量按需路由协议(AODV)的服务质量提出了越来越高的要求.为了提升AODV在无线传感器网络通信中的表现,文章提出了一种新型的基于AODV的多度量无线路由协议(MWR-AODV).MWR-AODV综合考虑了对路由协议性能影响重大的最小跳数、剩余能量、能量流失率和网络节点密度这四个因素,并且引入了一种低成本且高效的本地修复策略.通过Network Simulator-2仿真平台对MWR-AODV与标准AODV、DSDV协议的表现进行了仿真分析.结果表明,所提出的MWR-AODV能为无线传感器网络提供更好的通信服务,并且在均衡能量消耗延长网络寿命和平衡网络通信负载方面也有上佳表现.     

无线传感器网络UDHR协议的设计与实现

针对无线传感器网络(WSN)数据流的特点,提出一种WSN上下行路由异构的协议(UDHR),上下行路由可采用不同的算法,适合于时间驱动、事件驱动以及查询的数据收集模式.利用OMNeT++平台对UDHR协议进行建模仿真,结果表明该协议开销小、扩展性好、健壮稳定.并且在自主开发的Testbed平台上实现了该路由协议,利用该平台可实时观察整个WSN网络拓扑变化、网络开销、监测每个节点能量消耗以及数据收集等情况.     

无线Mesh网络多路径路由协议的研究

L2MPM路由协议工作在第2层,属于多经路由中的备份路由,但并未考虑主路经与备份路径之间存在链路相交的问题,降低了网络的容错能力。因此,在L2MPM协议的基础上,提出了LD-L2MPM路由协议。该协议通过采用链路不相交策略,在Hello包中添加第一跳和最后一跳字段来确保所选的两条路径是链路不相交。仿真结果表明,与原有协议相比,数据包投递率提高约6%,平均端到端时延降低约5%。     

Scalability enhancement of AODV using local link repairing

Dynamic change in the topology of an ad hoc network makes it difficult to design an efficient routing protocol. Scalability of an ad hoc network is also one of the important criteria of research in this field. Most of the research works in ad hoc network focus on routing and medium access protocols and produce simulation results for limited-size networks. Ad hoc on-demand distance vector (AODV) is one of the best reactive routing protocols. In this article, modified routing protocols based on local link repairing of AODV are proposed. Method of finding alternate routes for next-to-next node is proposed in case of link failure. These protocols are beacon-less, means periodic hello message is removed from the basic AODV to improve scalability. Few control packet formats have been changed to accommodate suggested modification. Proposed protocols are simulated to investigate scalability performance and compared with basic AODV protocol. This also proves that local link repairing of proposed protocol improves scalability of the network. From simulation results, it is clear that scalability performance of routing protocol is improved because of link repairing method. We have tested protocols for different terrain area with approximate constant node densities and different traffic load.