AD HOC网络路由协议的仿真及分析

Ad hoc网络是一种由移动节点组成、拓扑结构动态变化的自组织网络。介绍了Ad Hoc网络中常见的四种路由协议，利用NS进行了仿真，从网络时延、丢包率和路由开销方面对这四种路由协议仿真结果进行了分析比较。     

基于网络模拟的自组网路由协议分析

Ad Hoe网络是无须中心设施的无线网络,网络节点依靠自身寻找路由,这使得路由协议得到更多关注.为了考察传输层协议对路由性能的影响,文章在研究Ad Hoc网络典型路由协议工作原理的基础上,利用NS2网络仿真软件,分析了它们在UDP、TCP两种传输层协议下的性能变化.结果表明,采用UDP协议时,AODV总体性能对DSDV优势明显,而使用TCP协议时,AODV的性能略逊于DSDV.     

Ad Hoc网络路由技术

无线自组织网络(Adhoc)是一个复杂的系统,其中路由协议是该领域中的研究热点。通过采用合理的路由技术,可使无线自组网具有更为灵活的组网方式,从而达到提升网络性能、减少网络开销等目的。通过与认知无线电(CR)技术、协同通信(CC)技术以及多输入多输出(MIMO)天线技术等物理层新技术的有效结合,可以大大改善Adhoc路由协议的性能。     

多跳无线Ad hoc网络路由协议的模拟和性能比较

文中采用随机场景的模拟方法对3种多跳无线Ad hoc网络路由协议的性能做了定量性的分析.对网络模拟器NS-2做了更进一步的拓展:增加SASR路由协议、增加AODV的MAC层虚拟HELLO机制,在此基础上对路由协议AODV,DSR和SASR进行了模拟.模拟结果显示:3种路由协议都能适应网络的拓扑结构变化,但是SASR和AODV路由协议在多跳无线Ad Hoc网络仍然具有相对的优越性.     

即时无线移动网络及相关路由协议

即时无线网络需要设置固定的路由设备,网络中的每一个移动终端都可以充当路由器,即时无线网络的路由协议包括路由表驱动型路由协议和源节点发起型路由协议。本文分别以无线路由协议和即时指令型距离向量路由协议对上述两类协议进行了详细讨论。     

无线Ad Hoc网络中的QoS路由协议

无线Ad Hoc网络的应用环境以及与Internet的互连都要求其必须提供一定的服务质量(QoS)保证,QoS路由技术是在无线Ad Hoc网络中实现QoS的重要方法。本文对近年来国内外在无线Ad Hoc网络中的QoS路由技术方面取得的研究成果进行了全面的概括总结和分类,对资源预留路由、多径路由和跨层优化路由3类QoS路由协议进行比较分析,并且提出了QoS路由技术亟待解决的问题和今后的发展方向。     

无线Ad Hoc网络路由协议及性能分析

Ad Hoc网络是一种由移动节点组成、拓扑结构动态变化的自组织网络.网络中没有固定的网络基础设施.由于移动主机的通信范围有限,相距较远的主机需要通过其他主机的"多跳"转发才能通信,因此网络中的主机同时也作为路由器为其他主机转发报文.目前设计的各种Ad Hoc路由协议大多数并没有具体的性能分析与比较.本文介绍几种典型的路由协议DSDV,TORA,DSR和AODV,利用Ns-2进行仿真,并对仿真结果进行分析.     

两种移动Ad Hoc网络协议及其性能比较

主要比较了两种移动Ad hoc网络路由协议——动态源路由协议和Ad hoc按需距离矢量路由协议。这两种协议虽然有一些共性,不过它们协议本身的特点导致在不同的网络负荷、节点移动性等条件下有明显的性能差异。这些性能差异通过实验结果得到进一步分析,并对如何改进两种协议给出建议。     

自组网的路由协议及其QoS保障

自组网是一种新型的移动计算机网络，它应用广泛，并具有重要的商业价值。首先介绍了自组网的概念和特点，然后分析了自组网路由协议的特点与设计思路，并丰此基础上讨论了在自组网环境下实现QoS的策略与方法。     

Ad Hoc网络中路由协议的安全问题及认证式路由协议

对Ad Hoc网络中两个典型的按需路由协议AODV和DSR可能受到的各种攻击进行分析，然后介绍一种认证式路出协议（ARAN），该协议在路由发现、路由建立和路由维护过程中使用数字证书和数字签名的方式进行路由信息的认证，有效防止可能受到的攻击。最后通过计算机仿真验证认证式路由协议预防攻击的性能。     

Performance Evaluation of Routing Protocols for Ad Hoc Wireless Networks

A mobile ad hoc network is a collection of autonomous mobile nodes that communicate with each other over wireless links. Such networks are expected to play an increasingly important role in future civilian and military settings, being useful for providing communication support where no fixed infrastructure exists or the deployment of a fixed infrastructure is not economically profitable and movement of communicating parties is possible. However, since there is no stationary infrastructure such as base stations, mobile hosts need to operate as routers in order to maintain the information about the network connectivity. Therefore, a number of routing protocols have been proposed for ad hoc wireless networks. In this paper, we study and compare the performance of the following routing protocols AODV, PAODV (preemptive AODV), CBRP, DSR, and DSDV. A variety of workload and scenarios, as characterized by mobility, load and size of the ad hoc network were simulated. Our results indicate that despite its improvement in reducing route request packets, CBRP has a higher overhead than DSR because of its periodic hello messages while AODV's end-to-end packet delay is the shortest when compared to DSR and CBRP. PAODV has shown little improvements over AODV.     

基于能量有效的Ad hoc无线网络路由协议的研究

Ad hoc是一种无固定基础设施的特殊无线网络,此网络中节点一般由电池供能,需要考虑能量有效因素来最大化网络生命周期.对各类基于能量有效的Ad hoc无线网络路由协议进行比较和分析,可以看出路由协议对能量优化有着显著作用.     

移动Ad hoc网络中路由协议的研究

移动Ad hoc网络由无线移动节点在没有任何现存的网络基础设施的情况下组成的自治系统,成为一个具有任意通信拓扑图模型的通信网络.由于网络节点的多跳性、有限的传输带宽、高速移动性、能量受限等特点,使路由协议成为Ad hoc网络设计的关键.主要介绍了Ad hoc网络的路由协议设计策略及分类原则,并对现有的具有代表性的路由协议性能进行了比较分析,为进一步研究提出新的课题.     

Effectiveness of Reliable Routing Protocols in Mobile Ad Hoc Networks

Due to unpredictable topology change and frequent link failure, it becomes evident major challenge to provide the stable route between source and destination in mobile ad hoc networks. Unlike previous multipath routing schemes for redundancy and unicast routing protocol utilizing the longest route expiration time measured by geographical information supported by Global Positioning System (GPS), we develop a framework to establish the most stable route based on measured frequency of link failure, available battery as well as the number of actual connections. To evaluate performance of proposed scheme, we provide practical simulation results for multipath and unicast routing protocol in terms of packet delivery ratio, control overhead, average hop length as well as end-to-end delay. Through analysis of simulation results, we demonstrate that our scheme shows better performance than general unicast routing protocol as well as similar packet delivery ratio to multipath routing protocol with less maintenance overhead. Ki-Il Kim received the M.S. and Ph.D. degrees in computer science from the Chungnam National University, Daejeon, Korea, in 2002 and 2005, respectively. He is currently with Department of Information Science, Gyeongsang National University as a faculty member. His research interests include routing for MANET, QoS in wireless network, multicast, and sensor networks. Sang-Ha Kim received the B.S. degree in chemistry from Seoul National University, Seoul, Korea, in 1980. He received the M.S. and Ph.D. degrees in quantum scattering and computer science from the University of Houston, Houston, TX, in 1984 and 1989, respectively. From 1990 to 1991, he was with the Supercomputing Center, SERI, Korean Institute of Science and Technology (KIST) as Senior Researcher. He joined Chungnam National University, Daejeon, Korea, in 1992, where he is a Professor. His current research interests include wireless networks, ad hoc networks, QoS, optical networks, and network analysis.     

Survey of Secure Routing Protocols for Wireless Ad Hoc Networks

The mobile ad hoc network is a type of wireless network characterized by mobile nodes without a centralized administration. Frequent variations of the topology and the nature of the radio links have a negative impact on the stability of the links. Indeed, the link quality deteriorates rapidly and link breaks become frequent. To overcome these problems, new forms of routing protocols are used as the MultiPath routing. In addition, routing protocols require the knowledge of the nodes neighborhood to build and manage routes. The neighbor discovery process is performed by a Hello protocol. The Hello protocol typically involves several parameters such as the packet’s period; node’s transmit power, node’s position and node’s battery level. The purpose of this paper is to change the behavior of ad hoc On demand Multi-path Distance Vector (AOMDV) routing protocol by considering the density of the nodes as well as the interference of the neighboring nodes. This selection of paths goes through two stages. In the first step, we study the impact of the neighbor discovery process to select a set of paths having a minimum number of neighboring nodes to diminish contention problems and interference rate. In the second step, the Interference Ratio (IR) metric is used to select the paths in which the nodes are surrounded by a minimum of interference. We choose for our study two proposed approaches based on AOMDV routing protocol. The first is called AOMDV_neighbor and considers the density parameter as a path metric. The second is called AOMDV_neighbor_IR which considers the interference rate (IR) between each node and its neighborhood as a path metric. We evaluate the proposed routing protocols performance under various NS2 simulation scenarios in a shadowing environment.

     

移动Ad Hoc网络中的QoS路由协议研究

移动Ad Hoc网络是一种无线多跳自治系统网络，如何提供QoS保障是它面临的重要问题，其中QoS路由是一个关键技术。文章首先介绍了AdHoc网络的特点，并且介绍了其QoS保障技术。接着对当前AdHoc网络主要的路由协议进行了详细的分析与研究，并从几个方面进行了比较和分析。最后指出了Ad Hoc网络QoS路由协议中需要解决的问题和今后的研究方向。     

无线Ad hoc网络中QOS路由协议的研究

QoS保证体系在Ad hoc网络中扮演着重要的角色.在引入Ad hoc网络中QoS保证体系的基本组件和面临的新挑战之后,对其中的QoS路由协议进行了讨论,按照先应式、反应式、基于群集、利用地理位置信息、组播、多径等类别,对近几年来的各种研究成果进行了阐述和分析,并对未来的发展趋势进行了展望.     

Ad Hoc网络路由协议性能分析

介绍了移动自组网的表驱动和按需驱动两类路由协议.提出了定量评估网络路由协议性能的六个基本指标.利用网络仿真器NS-2,对四种典型的路由协议(DSR、DSDV、AODV和TORA)建立仿真模型,配置仿真参数,并进行了仿真.对仿真过程产生的文档进行处理,分析,比较它们的性能指标.试验结果表明,模型仿真结果接近理论分析和实际情况,该方法在路由协议研究,设计与仿真方面具有较强的实用性和通用性.     

基于定向天线的移动自组网路由协议研究

同等功耗下,定向天线能够产生更高的增益,提供更大的传输范围,提高网络的空间复用度和吞吐量,天线选择的方向性又降低了邻近结点之间的相互干扰,采用定向天线能够给移动自组网带来潜在性能的提高。对基于定向天线的移动自组网路由协议进行研究,简单介绍了定向天线,总结了引入定向天线产生的路由问题,对现有的一些典型定向路由协议进行了分类、介绍和比较,最后对引入定向天线带来的好处进行了分析。     

Ad Hoc网络中两种按需路由协议的比较

Ad hoc网络的特征是多跳的无线连接，网络拓扑的频繁变化，以及需要有效的动态路由协议。重点比较Ad hoc网络中两种主要的按需路由协议：动态源路由（DSR）协议和Ad hoc按需距离矢量路由（AODV）协议。尽管DSR和AODV都是按需路由协议，但不同的协议机制导致了网络性能的显著差异。在OPNET仿真平台下，对采用不用路由协议的网络时延和吞吐量进行比较，从而分析不同的路由机制引起的网络性能差异。