一种基于跨层的无线Mesh网络路由协议

无线Mesh网络的很多技术特点和优势来自于Mesh多跳路由.因此,路由协议的研究与设计是无线Mesh网络技术的一个重要课题.由于无线Mesh网络有自身负载均衡、路由容错与网络容量等要求,因此运用跨层设计,采用更好的路由参数,使用多径路由等方法已经成为无线Mesh网络路由协议设计的重要思路.根据无线Mesh的网络特点,按照其路由协议的设计要求,分析了路由协议DSR在Mesh网络中的不足,引入跨层设计的方法,提出了采用路由质量路径帧投递率(PFDR)为路由准则,并具有负载平衡、拥塞避免的路由协议CMRP.分析和仿真结果表明,CMRP在保持Mesh网络自身优点的同时,比起DSR在网络性能上有了较大的提升,在吞吐率方面有了很大的提高,相应的时延、抖动参数均有了大幅的下降,更加适用于无线Mesh网络.     

基于IEEE 802．11s的无线Mesh网络路由协议研究

基于IEEE802．11s的无线Mesh网络已成为机动宽带接入技术研究领域的一个研究热点。对无线Mesh网络中的关键技术——混合无线Mesh协议（HWMP）进行详细的分析,与传统按需路由机制相比,该协议既具有先验式路由协议的灵活性,亦具备按需路由协议的有效性,同时,对该协议度量机制做出改进,其将在应急通信等特殊应用环境中发挥重要作用。     

无线Mesh网络路由协议研究

无线Mesh网络WMN（wireless mesh networks）是一种新型的无线网络，它融合了无线局域网（WLAN）和Ad Hoc网络的优势，成为宽带接入的一种有效手段。首先介绍了无线Mesh网的网络结构和特点．并在此基础上讨论了无线Mesh网络对路由协议的要求。无线Mesh网络的路由算法是Mesh领域的研究难点，通过分析比较4种针对WMN的路由协议，总结了现有的路由协议的优缺点，并对今后的研究方向做出了展望。     

一种改进无线Mesh网络孤岛效应的路由算法研究

针对无线Mesh网络路由协议自身的缺陷而导致的孤岛效应,分析了其形成原因以及对网络的危害,通过对AODV、DSDV、DSR和TORA等典型路由协议的具体分析,提出动态传输距离算法,整理形成了改进的AODV路由协议,仿真结果表明,改进后的协议能够很好地解决Mesh孤岛效应。     

无线Mesh网络DSR路由协议改进方法的研究

目前国内外已经有许多研究对DSR路由协议进行改进,使其符合无线Mesh网络的结构特性.本文根据不同的优化原则如路由判据、QoS保证、负载均衡、跨层设计等,研究了各种优化原则下的DSR协议的改进思路,以及对现有的DSR协议改进算法进行了总结.     

无线MESH网络路由协议研究

无线Mesh网络WMN (wireless mesh networks)是近年来的研究热点之一,它融合了无线局域网(WLAN)和Ad Hoc网络的优势,为解决"最后一公里"问题提供了一种很有效的宽带接入手段.而无线Mesh网络的路由算法则是这个领域中的研究难点.本文首先介绍了无线Mesht网络的一些背景及其特点.然后对可以应用于无线Mesh网络的几种传统的路由协议进行了分析比较.最后简单介绍了当前这个领域的几种最新的无线Mesh网络路由算法.并展望了今后无线Mesh网络路由算法的研究前景.     

无线Mesh网络可信路由协议THWMP研究

为了使节点在网络中存在恶意节点和自私节点时能够选择安全可靠的路由,降低恶意节点和自私节点对无线Mesh网络带来的影响,文中通过对无线Mesh网络混合路由协议HWMP(Hybrid Wireless Mesh Protocol)和信任模型的研究,提出了基于主观逻辑信任模型的无线Mesh网络可信路由协议THWMP(Trusted HWMP),大大降低了因为信任的传递带来的网络开销,同时保证了路由的可信度。与HWMP路由协议相比较,在网络中存在恶意节点时,THWMP路由协议能够在增加有限的额外开销的情况下保证全网有较高的数据传递成功率和吞吐量。     

基于无线Mesh网络跨层协议研究

介绍无线Mesh网络的基本概念和特点,基于Mesh网络的相关MAC协议和路由协议,从物理层、MAC层、路由协议层等层面介绍WMN跨层设计的一般原则和方法,对WMN的跨层设计方法和方案进行了阐述,对目前Mesh网络中的传统OSI分层结构参考模型存在的问题进行了分析,提出需要进一步研究的问题。     

无线Mesh网路由协议仿真及性能分析

当前对无线网格网络（Mesh网络）主要研究之一是无线路由技术,即针对无线Mesh网络自身的特点进行路由设计。在熟悉基于Linux平台的网络仿真器（NS2）针对Mesh网络路由协议的仿真过程的基础上,利用NS2网络仿真软件分别从端到端平均时延、分组递交率、归一化路由开销三个方面比较了目前三种典型的路由协议——按需平面距离矢量路由（AODV）、动态源路由（DSR）和目的序列距离矢量路由（DSDV）的性能,并详细介绍了整个仿真过程的步骤。最后,通过分析AODV协议的吞吐量,得出网络最佳容纳的节点数,研究成果对协议的实现具有重要的应用价值。     

Mesh网下AODV、DSR和ZigBee路由的比较分析

为了研究在Mesh拓扑网络下不同无线自组网络路由协议的性能优劣,在网络设计中有选择地使用,分析和研究了ZigBee路由、动态源路由协议（DSR）和平面距离矢量路由协议（AODV）三种无线自组网络路由协议的思想和原理。通过网络模拟软件NS-2,在其他外部条件相同的条件下对三者在Mesh拓扑结构组网进行模拟,得到端到端平均延迟、包传输率和路由开销率三种性能指标的折线图。从仿真结果图上看,ZigBee路由在其应用范围内具有独特优势,适合在Mesh拓扑网络中应用。     

Mobile Multihop Ad Hoc Networks: Simulation and Study

In this work we propose the use of more detailed graphics to study the performance of routing protocols for mobile multihop ad hoc networks when studying the feasibility of providing quality of service to upper layer real--time applications. Classic success ratio and round trip time curves provide important parameters to study and compare routing protocols, but they also mask valuable information about the evolution of the network. This masquerading is due to the averaging techniques used in classic curves. The dynamic behavior of the network makes these curves inappropriate when analyzing routing protocols with quality of service constraints. In order to obtain more detailed graphics, we propose the use of time windows and discrimination of the results on a per link basis. Our proposal provides better comprehension of the routing protocol characteristics and its applicability to quality of service in mobile multihop ad hoc networks.     

面向Ad Hoc网络的QoS路由研究

节点可以自由自主地进入网络拓扑并且无须基础网络设施的特性，使得移动Ad Hoc网络应用广泛，同时也使得它在提供一定的服务质量（QoS）时面临许多新的挑战，本文通过Ad Hoc网络QoS的体系结构设计和支持QoS的路由算法设计两个方面来考虑，对近年来国内外在这方面的研究成果作了全面的概括总结和比较分析。     

自组网路由协议综述

自组网路由协议用于监控网络拓扑结构变化,交换路由信息,定位目的节点位置,产生、维护和选择路由,并根据选择的路由转发数据。本文综述了自组网路由协议研究方面的一些最新工作,描述了设计自组网路由协议所面临的问题,并着重对该研究开展以来所提出的各种主要协议进行了对比、分析和分类阐述,为进一步的研究提出了新的课题。     

Efficient flooding with passive clustering-an overhead-free selective forward mechanism for ad hoc/sensor networks

High capacity real-time data communications in sensor networks usually require multihop routing and ad hoc routing protocols. Unfortunately, ad hoc routing protocols usually do not scale well and cannot handle dense situations efficiently. These two issues-scalability and density-are the major limitations when we apply ad hoc routing schemes to sensor networks. Passive clustering (PC) classifies ad hoc/sensor nodes into critical and noncritical nodes without any extra transmission. By 2-b piggybacking and monitoring user traffic (e.g., data polling requests from a sink), PC deploys the clustering structure "for free". Moreover, PC makes even the first flooding as efficient as all subsequent floodings (i.e., no initialization overhead). PC introduces many benefits, including efficient flooding and density adaptation. As a result, PC reduces control overhead of ad hoc routing protocols significantly and, as a consequence, enables ad hoc routing in large, dense sensor networks. The resulting structure can be utilized in cluster-based ad hoc network/sensor networking as well as for active node selection.     

Comparison of two routing metrics in OLSR on a grid based mesh network

Predicting the performance of ad hoc networking protocols for mesh networks has typically been performed by making use of software based simulation tools. Experimental study and validation of such predictions is a vital to obtaining more realistic results, but may not be possible under the constrained environment of network simulators. This paper presents an experimental comparison of OLSR using the standard hysteresis routing metric and the ETX metric in a 7 by 7 grid of closely spaced Wi-Fi nodes to obtain more realistic results. The wireless grid is first modelled to extract its ability to emulate a real world multi-hop ad hoc network. This is followed by a detailed analysis of OLSR in terms of hop count, routing traffic overhead, throughput, delay, packet loss and route flapping in the wireless grid using the hysteresis and ETX routing metric. It was discovered that the ETX metric which has been extensively used in mesh networks around the world is fundamentally flawed when estimating optimal routes in real mesh networks and that the less sophisticated hysteresis metric shows better performance in large dense mesh networks.     

Power-aware routing protocols in ad hoc wireless networks

An ad hoc wireless network has no fixed networking infrastructure. It consists of multiple, possibly mobile, nodes that maintain network connectivity through wireless communications. Such a network has practical applications in areas where it may not be economically practical or physically possible to provide a conventional networking infrastructure. The nodes in an ad hoc wireless network are typically powered by batteries with a limited energy supply. One of the most important and challenging issues in ad hoc wireless networks is how to conserve energy, maximizing the lifetime of its nodes and thus of the network itself. Since routing is an essential function in these networks, developing power-aware routing protocols for ad hoc wireless networks has been an intensive research area in recent years. As a result, many power-aware routing protocols have been proposed from a variety of perspectives. This article surveys the current state of power-aware routing protocols in ad hoc wireless networks.     

一种实用的适用于移动自组织网络的认证协议

与传统网络相比，自组织网络本身存在许多系统脆弱性．使得传统网络安全机制不再适用于自组织网络。文章对传统PKI作必要改进，定义了适用于自组织网络的的公钥基础设施AH-PKI．并设计了一种基于AH-PKI的认证协议。     

Efficient routing for wireless mesh networks using a backup path

Wireless mesh networks (WMNs) have a proven record in providing viable solutions for some of the fundamental issues in wireless networks such as capacity and range limitations. WMN infrastructure includes clusters of mobile ad‐hoc networks connected through a fixed backbone of mesh routers. The mesh network can be constrained severely because of various reasons, which could result in performance degradation such as a drop in throughput or long delays. Solutions to this problem often focus on multipath or multichannel extensions to the existing ad‐hoc routing protocols. In this paper, we propose a novel solution by introducing an alternative path to the mesh backbone that traverses the mobile ad‐hoc networks part of the WMN. The new routing solution allows the mobile nodes (MNs) to establish direct communication among peers without going through the backbone. The proposed alternative ad‐hoc path is used only when the mesh backbone is severely constrained. We also propose, for the first time in WMNs, using MNs with two interfaces, one used in the mesh backbone communication and the other engaged in the ad‐hoc network. A scheme is presented for making the MN aware of link quality measures by providing throughput values to the ad‐hoc on‐demand distance vector protocol. We use piggybacking on route reply messages in ad‐hoc on‐demand distance vector to avoid incurring additional costs. We implemented our solution in an OPNET simulator and evaluated its performance under a variety of conditions. Simulation results show that the alternative ad‐hoc path provides higher throughput and lower delays. Delay analysis show that the throughput improvement does not impose additional costs. Copyright © 2012 John Wiley & Sons, Ltd.     

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.     

Provably Secure On-Demand Source Routing in Mobile Ad Hoc Networks

Routing is one of the most basic networking functions in mobile ad hoc networks. Hence, an adversary can easily paralyze the operation of the network by attacking the routing protocol. This has been realized by many researchers and several "secure" routing protocols have been proposed for ad hoc networks. However, the security of those protocols has mainly been analyzed by informal means only. In this paper, we argue that flaws in ad hoc routing protocols can be very subtle, and we advocate a more systematic way of analysis. We propose a mathematical framework in which security can be precisely defined and routing protocols for mobile ad hoc networks can be proved to be secure in a rigorous manner. Our framework is tailored for on-demand source routing protocols, but the general principles are applicable to other types of protocols too. Our approach is based on the simulation paradigm, which has already been used extensively for the analysis of key establishment protocols, but, to the best of our knowledge, it has not been applied in the context of ad hoc routing so far. We also propose a new on-demand source routing protocol, called endairA, and we demonstrate the use of our framework by proving that it is secure in our model