一种应用于移动Ad hoc网络的可扩展路由协议

移动Ad hoc网络是一种高度动态的无线网络,路由成为其实际应用中必须解决的关键问题.目前基于拓扑的MANET路由协议大多不具有良好的可扩展性.为此面向Ad hoc组网应用,提出一种具有可扩展性的中心控制路由协议.仿真结果和性能分析表明,在大型Ad hoc网络组网中,该路由协议具有较好的可扩展性和较高的分组递送率,并提供了QoS路由实现手段.     

基于NS-2的Ad hoc网络路由协议性能研究

移动Ad hoc是下一代网络(NGN)的重要组成部分,无需固定基础设施的临时网络.重点研究了目前典型的Ad hoc网络的路由协议,设计并实现了在NS-2环境下典型协议的仿真场景和性能分析比较.对Ad hoc路由协议的研究和组网具有参考指导意义.     

基于NS-2的MANET网络路由协议DSR性能研究

移动Ad hoc网络(MANET)是一组无线主机组成的没有任何建立好的基础设施的临时网络,网络拓扑高度变化自组织网络,由于其特点的限制,路由协议是其组网的关键技术和具有挑战性的问题之一,本文研究了典型的路由协议DSR的工作原理,设计了在NS-2中的仿真场景来研究分析DSR路由协议的性能和在移动网络环境中的适应性。对Ad hoc的组网和后续协议的研究具有指导意义。     

Ad hoc 网络组播路由协议研究现状、问题和方向

移动终端设备的快速发展和Ad hoc网络组网方便的特点使得Ad hoe网络有着广阔的应用前景，而组播路由技术在这些应用中起着非常重要的作用。本文综述了Ad hoe组播路由协议研究方面的一些最新工作，描述了设计Ad hoc组播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组播协议进行了分类阐述和对比、分析，最后讨论了设计组播路由协议的几个主要问题，同时指出了未来的研究方向。     

基于定位信息的Ad hoc路由协议

基于定位信息的路由协议的功能大大优于传统的Ad hoc路由协议,但基于定位信息的路由协议不能用于高风险环境.本文所介绍的Ad hoc网络基于定位信息的安全型路由协议"Secure Position Aided Ad hoc Routing"(SPAAR)目的在于提高移动Ad hoc路由的安全性、有效性和性能.     

可扩展的MAODV协议

随着近年来人们对移动Ad hoc网络和多播兴趣的日益增加,出现了许多适用于MANET上的多播路由协议.该文综述了这些移动Ad hoc网络上的多播协议,介绍了MAODV协议,提出了一种新的多播路由可扩展性解决方案.模拟结果显示,采用提出的技术增强了多播路由协议的性能和可扩展性.     

移动模型对Ad hoc网络路由协议能耗的影响

Ad hoc网络节点能量受限的路由协议的研究是目前的一个热点，IETF的MANET小组提出的几种经典的路由协议，属于最短路由，即最小跳数路由，没有考虑能量因素。由于Ad hoc网络中的节点是由电池供电，整个网络是一个能量受限系统，如何节省节点的能量，尽可能延长网络的可操控时间成为衡量路由协议性能的重要指标。目前针对这几种路由协议基于节点能量约束的评估很少。基于移动模型，该文以能量消耗程度为指标，对Ad hoc 4种典型的路由协议在不同的运动场景下进行了比较系统的仿真研究，得出了一些有益的结论，为进一步研究基于能耗的Ad hoc网络路由协议提供一些参考。     

移动Ad hoc网络路由安全性研究

路由协议安全性问题是移动Ad hoc网络研究重要课题。对移动Ad hoc网络路由协议中存在的安全问题和典型解决方案做了综述和分析。根据所适用的算法,将安全路由协议及其改进策略进行了分类。对路由安全性研究有较好的借鉴意义。     

移动Ad Hoc网络路由协议研究分析

移动Ad Hoc网络是随着无线通信技术的快速发展而出现的一种新型网络。由于Ad Hoc网络自身的特殊性，其路由协议的设计与传统固定网络有很大不同。文章描述了Ad Hoc网络中路由协议设计所面临的问题，讨论了Ad hoc网络中路由协议设计的几种策略。对现行的Ad Hoc网络路由协议进行了时比、分析和分类阐述，为进一步研究提出了新的课题。     

移动Adhoc网络安全路由协议研究

移动Ad hoc网络是由一组移动终端组成的无线多跳自治系统,具有无中心、自组织、多跳路由、动态拓扑结构等特点.尽管有带宽受限等缺点,但无线Ad hoc网络具备灵活机动、组网迅速的优势,在军事通信、民用通信和各种临时通信中具有广阔的应用前景.近来其路由技术、Qos、安全性问题,尤其是路由协议的安全成为研究的热点.介绍了针对其路由协议的攻击,重点分析比较了典型的移动Ad hoe网络安全路由协议,最后指出下一步研究的方向.     

Survey of network coding-aware routing protocols in wireless networks

In recent times, there have been many advances in the field of information theory and wireless ad hoc network technologies. Regarding information theory progression and its connection with wireless ad hoc networks, this study presents fundamental concepts related to the application of the state-of-the-art Network Coding (NC) within wireless ad hoc networks in the context of routing. To begin with, this paper briefly describes opportunistic routing and identifies differentiation between NC-aware and NC-based routing mechanisms in wireless ad hoc networks. However, our main focus is to provide a survey of available NC-aware routing protocols that make forwarding decisions based on the information of available coding opportunities across several routes within wireless ad hoc networks. The taxonomy and characteristics of various representative NC-aware routing protocols will also be discussed. In summary, we provide a comparison of available NC-aware routing schemes and conclude that NC-aware routing techniques have several advantages over traditional routing in terms of high throughput, high reliability, and lower delay in a wireless scenario. To the best of our knowledge, this work is the first that provides comprehensive discussion about NC-aware routing protocols.     

QoS routing with traffic distribution in mobile ad hoc networks

Mobile ad hoc networks (MANETs) follow a unique organizational and behavioral logic. MANETs’ characteristics such as their dynamic topology coupled with the characteristics of the wireless communication medium make Quality of Service provisioning a difficult challenge. This paper presents a new approach based on a mobile routing backbone for supporting Quality of Service (QoS) in MANETs. In real-life MANETs, nodes will possess different communication capabilities and processing characteristics. Hence, we aim to identify those nodes whose capabilities and characteristics will enable them to take part in the mobile routing backbone and efficiently participate in the routing process. Moreover, the route discovery mechanism we developed for the mobile routing backbone dynamically distributes traffic within the network according to current network traffic levels and nodes’ processing loads. Simulation results show that our solution improves network throughput and packet delivery ratio by directing traffic through lowly congested regions of the network that are rich in resources. Moreover, our protocol incurs lower communication overheads than AODV (ad hoc on-demand distance vector routing protocol) when searching for routes in the network.     

RDSR-V. Reliable Dynamic Source Routing for video-streaming over mobile ad hoc networks

Mobile ad hoc networks (MANETs) are infrastructureless networks formed by wireless mobile devices with limited battery life. In MANETs for civilian applications, the network nodes may not belong to a single authority and they may not have a common goal. These MANETs are particularly vulnerable to selfish behavior, as some nodes may prefer saving resources to forward data. There are a few generic reputation-based systems for MANETs which could be used to enforce cooperation among nodes. However, we envision that the system performance can be highly improved by using cross-layer techniques that take into account the specific characteristics of each particular service. In this article, we propose a distributed and easy-to-implement routing mechanism based on reputation for the provision of MPEG-2 video-streaming services over MANETs. The main novelty that we introduce regarding the existent literature is that our proposal is service aware, that is to say, we consider the video-streaming service characteristics to develop a cross-layer design with the routing protocol. In addition, we do not introduce extra signaling overhead to monitor reputation because we use the standard video-streaming end-to-end signaling. Finally, simulation results show that our proposal clearly outperforms both standard Dynamic Source Routing (DSR) and OCEAN (a generic reputation-based mechanism).     

无线自组织网络中CBRP路由算法改进

移动自组织网络(MobileAdHocNetworks)是一种完全由无线移动主机自主构成的通信网络,常用在需要紧急或临时搭建网络的环境下,具有带宽有限和拓扑结构易变等特点。为了提高AdHoc网络路由算法性能,实现并分析了IETF提出的基于层次化“簇”结构的CBRP路由算法协议(ClusterBasedRoutingProtocol),并提出了针对CBRP算法的网关节点选择优化机制和网络结构维护优化策略。最后通过单台计算机对一组具有不同终端节点的网络小区进行仿真。其结果表明,优化后的算法提高了紧急情形和恶劣环境下CBRP路由算法的性能。     

Differentiation, QoS guarantee, and optimization for real-time traffic over one-hop ad hoc networks

Nodes having a self-centrically broadcasting nature of communication form a wireless ad hoc network. Many issues are involved to provide quality of service (QoS) for ad hoc networks, including routing, medium access, resource reservation, mobility management, etc. Previous work mostly focuses on QoS routing with an assumption that the medium access control (MAC) layer can support QoS very well. However, contention-based MAC protocols are adopted in most ad hoc networks since there is no centralized control. QoS support in contention-based MAC layer is a very challenging issue. Carefully designed distributed medium access techniques must be used as foundations for most ad hoc networks. In this paper, we study and enhance distributed medium access techniques for real-time transmissions in the IEEE 802.11 single-hop ad hoc wireless networks. In the IEEE 802.11 MAC, error control adopts positive acknowledgement and retransmission to improve transmission reliability in the wireless medium (WM). However, for real-time multimedia traffic with sensitive delay requirements, retransmitted frames may be too late to be useful due to the fact that the delay of competing the WM is unpredictable. In this paper, we address several MAC issues and QoS issues for delay-sensitive real-time traffic. First, a priority scheme is proposed to differentiate the delay sensitive real-time traffic from the best-effort traffic. In the proposed priority scheme, retransmission is not used for the real-time traffic, and a smaller backoff window size is adopted. Second, we propose several schemes to guarantee QoS requirements. The first scheme is to guarantee frame-dropping probability for the real-time traffic. The second scheme is to guarantee throughput and delay. The last scheme is to guarantee throughput, delay, and frame-dropping probability simultaneously. Finally, we propose adaptive window backoff schemes to optimize throughput with and without QoS constraints.     

Ad hoc无线网络负载自适应平衡跨层多径路由算法

提出了一种Ad hoc无线网络流量自适应平衡的多径路由选择算法LACLMRA。算法LACLMRA利用网络的跨层信息：传输层提供的数据端到端传输延迟、节点MAC层提供的最近一次传输成功前重传次数、网络层的缓存队列长度等信息,构建多条不相交的多径路由。在实际的数据传输过程中,根据路由的质量,在多条路径中自适应分配流量,缓解节点的拥塞,延长Ad hoc无线网络的生存时间。仿真结果也显示该算法与SMR、AOMDV等多径路由算法相比,在降低网络平均延迟、提高吞吐量、延长网络生存时间方面,有更好的表现。     

Two-tier authentication for cluster and individual sets in mobile ad hoc networks

Mobile ad hoc networks (MANETs) have been proposed as an extremely flexible technology for establishing wireless communications. In comparison with fixed networks or traditional mobile cellular networks, some new security issues have arisen with the introduction of MANETs. Routing security, in particular, is an important and complicated issue. In this work, we propose a two-tier authentication scheme for cluster and individual sets, in MANETs. The first tier, based on a hash function and the MAC concept, provides fast message verification and group identification. The second tier, based on secret sharing technology, provides secure user identification. The scenario of two-tier authentication can prevent internal and external attacks, including black holes, impersonation, routing table overflows and energy consummation attacks.     

移动Ad Hoc网络路由协议的性能分析与比较

移动Ad Hoe网络是由一组无线移动主机组成的一个没有任何建立好的基础设施或集中管理设备的临时网络.网络拓扑易变、带宽、能源有限是移动Ad Hoe网络的主要特点.分析表驱动路由协议DSDV和按需路由协议DSR、AODV和TO-RA,并利用NS2软件进行了仿真实验,通过改变节点的暂停时间和移动速度这两个参数来比较这两个参数对这四种协议性能的影响.仿真结果表明,按需路由协议在分组投递率、端到端的平均时延、路由开销方面都表现出较好的性能.但同时结合表驱动路由协议的特点,为进一步在综合考虑以上两类路由协议特点的基础上研究新的路由协议提供很好的参考.     

MANET中基于位置的无信标路由算法与DSR的性能比较

由于节点的移动性、无线链路的带宽有限、可获得的能量有限等原因,对移动Ad hoc网络进行路由提出了具有挑战性的要求。基于位置的路由协议由于不必维护明确的路由,在这种高度动态的网络中具有很好的扩展性。该文通过仿真将一种基于位置的贪婪转发路由:基于改进进程无信标路由(IPPBBLR),与一种基于拓扑的路由:动态源路由(DSR)进行了性能比较。仿真结果表明基于位置的路由比基于拓扑的路由在移动的情况下可以达到更高的发送成功率和更小的端到端延迟,且端到端延迟几乎不受移动速率的影响。