多跳无线移动Ad Hoc网络路由协议的研究分析

无线移动Ad Hoe网络(MANET)作为可移动分布式多跳无线网络，没有预先确定的网络拓扑或网络基础设施以及集中控制．为了在如此的网络中促进通信，路由协议主要用于在节点之间发现路径．Ad Hoe网络路由协议的主要目的是网络拓扑的动态变化、任意两个节点之间建立一个使得通信总费用和带宽消费最少的正确和有效的通信路径．描述了设计移动Ad Hoe网络路由协议所面临的问题以及对它们的评价，详细比较了七种典型无线移动AdHoe网络路由协议的特性和功能，即DSDV，CGSR，WRP，AODV，DSR，TORA和ABR，为进一步的研究提出了新的课题．     

A low-overhead fault-tolerant routing algorithm for mobile ad hoc networks: A scheme and its simulation analysis

The fault-prone nodes in a mobile ad hoc network (MANET) degrade the performance of any routing protocol. Using greedy routing mechanisms that tend to choose a single path every time, may cause major data losses, if there is a breakdown of such a path in a fault-prone environment. On the other hand, using all the available paths causes an undesirable amount of overhead on the system. Designing an effective and efficient fault-tolerant routing protocol is inherently hard, since the problem is NP-complete because of the unavailability of precise path information in adversarial environments [1].To address the above mentioned problem, we present a fault-tolerant routing algorithm (FTAR), which bases on the ideas of foraging in natural ants [2]. The algorithm is divided into six stages, namely, initialization, path selection, pheromone deposition, confidence calculation, evaporation and negative reinforcement. Simulation results show that FTAR achieves high packet delivery ratio and throughput as compared to some of the key protocols which do not address fault-tolerance at all. Most importantly, FTAR is established to supersede the performance of one of the best fault-tolerant MANET routing schemes [1] known currently, with respect to the amount of routing overhead incurred – it is an important achievement for ad hoc networks.     

基于贪婪覆盖集的MANET自适应组播路由算法研究

MANET所具有的分布式、多跳、自组织、动态拓扑、时变信道、资源受限等特点,使得传统的有线网和有中心无线网络的路由算法和协议无法在MANET中直接应用,为此需要根据MANET的特点设计专门的组播路由算法和协议.结合基于Mesh和基于树形转发结构两类MANET组播路由的优点,提出一种基于贪婪覆盖集(Greedy Set Cover)的MANET组播路由算法ADMMR(Adaptive Distributed MANET Multicast Route based on Greedy Set Cover),节点可以动态地、分布式计算各自的转发列表,根据转发列表进行组播数据的转发,节省有限的带宽,减少信道冲突,降低网络负载,提高算法的总体性能.最后运用OPNET验证了该算法的有效性.     

Routing with adaptive path and limited flooding for mobile ad hoc networks

In MANET, each mobile host can freely move around and the network topology is dynamically changing. To send a datagram, a source host broadcasts a route discovery packet to the network. All neighboring nodes receiving this packet will rebroadcast this packet until it reaches the destination. It will have large flooding overhead, poor network performance and undesirable battery power consumption. To improve network performance, we design a novel routing protocol called RAPLF (Routing with Adaptive Path and Limited Flooding) for mobile ad hoc networks. Simulation results show that our protocol has better performance especially in packet delivery rate and flooding overhead when compared to similar protocols.     

一种基于改进RTS/CTS的MANET高效报文转发策略

MANET网络由可自主移动的无线节点组成。节点的自主移动导致了链路路由的改变,因此需要有一个机制维护和发现路由信息。目前人们已经针对MANET网络提出了几种路由协议,但这些路由协议都是基于IP的且路由维护的代价高,这严重影响了MANET网络的稳定性、可扩展性和用户有效带宽。本文提出了一种基于改进RTS/CTS的MANET高效报文转发策略。该策略对标准IEEE 802.11协议进行了修改,利用改进的RTS/CTS报文信息,进行报文转发,从而避免了使用MANET网络路由协议给网络性能带来的影响。使用改进的NS-2模拟了基于改进RTS/CTS的MANET高效报文转发策略。模拟结果表明:该策略可以有效地降低路由维护的开销并降低报文传输的延迟。     

Anonymous Geo-Forwarding in MANETs through Location Cloaking

In this paper, we address the problem of destination anonymity for applications in mobile ad hoc networks where geographic information is ready for use in both ad hoc routing and Internet services. Geographic forwarding becomes a lightweight routing protocol in favor of the scenarios. Traditionally the anonymity of an entity of interest can be achieved by hiding it among a group of other entities with similar characteristics, i.e., an anonymity set. In mobile ad hoc networks, generating and maintaining an anonymity set for any ad hoc node is challenging because of the node mobility, consequently the dynamic network topology. We propose protocols that use the destination position to generate a geographic area called {em anonymity zone (AZ)}. A packet for a destination is delivered to all the nodes in the AZ, which make up the anonymity set. The size of the anonymity set may decrease because nodes are mobile, yet the corresponding anonymity set management is simple. We design techniques to further improve node anonymity and reduce communication overhead. We use analysis and extensive simulation to study the node anonymity and routing performance, and to determine the parameters that most impact the anonymity level that can be achieved by our protocol.     

基于表驱动的最佳动态路由代理MANET路由算法

MANET(mobileadhocnetworks)是由无线移动节点动态地构成的一个临时网络,它不需要任何固定的网络基础设施或网络管理中心。由于无线传输的范围有限,因此,一个节点要和另一个节点交换信息可能通过多跳的方式跨越另一个网络。文章在基于路由表驱动的基础上,针对MANET提出了一个提高带宽利用率,适应网络拓扑结构动态变化的路由算法,并与DSDV,GSR做了对比。     

Dynamic address autoconfiguration in hybrid ad hoc networks

The use of ad hoc networking technologies is emerging as a viable and cost-effective solution to extend the range of traditional wireless local area networks (WLANs). In these networks, mobile client traffic reaches the access points through multi-hop wireless paths that are established by using an ad hoc routing protocol. However, several technical challenges have to be faced in order to construct such an extended WLAN. For instance, traditional autoconfiguration protocols commonly used in infrastructure-based WLANs, such as DHCP or Zeroconf, are not directly applicable in multi-hop wireless networks. To address this problem, in this paper we propose extensions to DHCP to enable the dynamic allocation of globally routable IPv4 addresses to mobile stations in hybrid ad hoc networks, which transparently integrate conventional wired technologies with wireless ad hoc networking technologies. Some of the attractive features of our solution are its ability to cope with node mobility, the introduction of negligible protocol overheads, and the use of legacy DHCP servers. We have implemented a prototype of our scheme, and tested its functionalities considering various topology layouts, network loads and mobility conditions. The experimental results show that our solution ensures short address configuration delays and low protocol overheads.     

移动自组网络中一种有效的选播路由协议

移动自组网是一种特殊的无线移动通信网络，它由一系列带有无线收发装置的动态节点临时形成一个多跳的自治系统，因此传统网络中的路由协议不适合于移动自组网络．选播作为一类新的通信协议，能有效平衡网络负载分布和提高网络性能．本文首先描述了移动自组网络的特点及该环境下的路由协议，在此基础上提出了一种有效的选播路由协议．通过平均分组传送成功概率和平均控制字节数指标的测试表明了算法的有效性．     

Using particle swam optimization for QoS in ad-hoc multicast

A mobile ad hoc network (MANET) is a collection of self-organized mobile nodes that are capable of communicating with each other without the aid of any established infrastructure or centralized administration. Multicasting plays a very important role in the application of ad hoc networks. As the number of participants increases, scalability of the multicast protocol becomes an important issue. When considering the increasing demand of Quality-of-Service (QoS) requirements in many applications, the existing multicast routing protocols used for ad-hoc network should be adapted appropriately to effectively meet the stringent QoS requirements of specific multimedia traffic. We thus propose a multicast routing protocol which tries its best to meet the variation of behavior of network topology and satisfy QoS requirements of specific multimedia traffic using particle swam optimization (PSO) in the volatile environments of a MANET. Meanwhile, a priority scheduler with PSO is also proposed to make scheduling decisions so that the packet loss rate can be further reduced. The results of a series of simulations exhibit the practicability and feasibility of our protocol.     

移动自组网基于路径维持概率的按需路由协议

在移动自组网(mobile ad hoc networks,简称MANET)中,节点的移动使无线链路经常发生断裂,从而导致路由无效.为了提高路由的稳定性,在分析单跳链路的t-时间维持概率的基础上,提出了一种基于路径t-时间维持概率的按需路由协议.该协议通过目的节点对路由请求的二次应答和中间节点对路由的反向优化来选择具有最大t-时间维持概率的路径,从而延长了路由的维持时间.仿真结果表明:与AODV(ad hoc on-demand distance vector)和DSR(dynamic source ro     

两种Ad hoc网络组播路由协议的性能比较和分析

目前研究人员已提出多种Adhoc网络组播路由协议,根据MANET制定的路由协议性能评价标准,还没有一种组播路由协议能满足所有的性能要求,因此对协议在各种应用环境下的性能进行测试和比较,有助于人们选择和设计组播路由协议。该文首先介绍了两种组播路由协议—ODMRP和DBRMP的基本思想,接着提出这两种协议的控制开销计算方法,并对它们的性能进行了定性比较,最后使用了NS-2仿真平台对两种组播路由协议在各种应用环境下的性能进行了仿真,并根据仿真结果详细比较和分析了两种协议在各种应用环境下的性能特点。     

一种移动Ad Hoc网络中身份认证与地址分配方案

现有ad hoc网络协议都是假设节点进入网络时已经分配了IP地址，而且在节点进入网络时假设节点之间无条件信任，这种缺乏对安全性的考虑是无法在实际战场环境下使用的。该文提出一种新的安全的解决方案，它由建立路由前的节点间的相互身份认证和安全地址分配(公钥散列产生节点地址)两个部分组成。方案可以有效地防止各种相关的攻击，最后还进行了方案的效率分析。     

The performance impact of traffic patterns on routing protocols in mobile ad hoc networks

As mobile ad hoc network (MANET) systems research has matured and several testbeds have been built to study MANETs, research has focused on developing new MANET applications such as collaborative games, collaborative computing, messaging systems, distributed security schemes, MANET middleware, peer-to-peer file sharing systems, voting systems, resource management and discovery, vehicular computing and collaborative education systems. The growing set of diverse applications developed for MANETs pose far more complex traffic patterns than the simple one-to-one traffic pattern, and hence the one-to-one traffic pattern widely used in previous protocol studies has become inadequate in reflecting the relative performance of these protocols when deployed to support these emerging applications.As a first step towards effectively supporting newly developed and future diverse MANET applications, this paper studies the performance impact of diverse traffic patterns on routing protocols in MANETs. Specifically, we propose a new communication model that extends the previous communication model to include a more general traffic pattern that varies the number of connections per source node. We study the performance impact of traffic patterns on various routing protocols via detailed simulations of an ad hoc network of 112 mobile nodes. Our simulation results show that many of the conclusions drawn in previous protocol comparison studies no longer hold under the new traffic patterns. These results motivate the need for performance evaluation of ad hoc networks to not only include rich and diverse mobility models as has been done in the past but also include diverse traffic patterns that stress a wide set of protocol design issues.     

大规模移动自主网络中基于簇的QoS多路径路由

在移动自主网络中,提供服务质量支持是一个核心研究问题.大量研究表明,在移动自主网络中提供服务质量保障具有很大的挑战性.提出一个基于簇的QoS多路径路由协议(CQMRP),通过一种可扩展、灵活的方式为移动自主网络提供服务质量保证.在这个策略中,每个节点只维持局部路由信息而不是整个网络的全局状态信息.它支持多个服务质量约束.采用OPNET模拟器对协议性能进行了评估,结果表明,这个协议能够为移动自主网络提供一个可靠的多路径服务质量保证.     

基于模糊控制的Ad Hoc网络QoS优先调度算法

无线移动Ad Hoc网络(MANET)作为可移动分布式多跳无线网络,没有预先确定的网络拓扑或网络基础设施以及集中控制.由于移动Ad Hoc网络的动态性和资源的限制,在如此的网络中提供QoS保障是一个挑战性任务.Ad Hoc网络的分组优先级凋度算法将增进网络的性能.提出了一个基于模糊控制的Ad Hoc网络QoS优先调度算法,用于决定Ad Hoc网络中分组的优先级.利用NS2仿真软件对分组的传输率、平均端对端的延迟等做了性能分析,仿真结果表明,该方法高效、可行,可应用于Ad Hoc网络.     

移动自组网的安全路由协议

移动自组网（MANET）是自治的无基础设施的网络,它通过IP路由支持多跳无线通信,它被用于没有基础设施存在的动态变化的场景。多数自组网路由协议利用节点之间固有特性即相邻节点的信赖关系进行协作转发数据包。这种信赖模型使得恶意节点利用插入错误的路由更新、重放过时的路由信息、改变路由更新、或广播不正确的路由信息来瘫痪自组网。针对自组网的缺陷提出了一种认证路由策略来解决这些问题,同时也列举了仿真实验结果。     

基于OLSR的MANET地址自动配置机制

为了解决现有无线自组织网络地址自动配置协议过于复杂、开销大、可实现性不强的问题,利用OLSR在全网拓扑信息维护、低开销消息洪泛等方面的优势,提出一种以OLSR为基础的地址自动配置方案。实现IP地址的快速分配,并只需对OLSR协议消息作简单修改即可在网络运行过程中维护地址的唯一性。所提出的方案具有开销低、实现简单的特点,适合大型网络地址分配需要。     

基于群组移动模型的OLSR协议性能仿真与评估

在研究移动自组网移动模型和无线路由协议的基础上,选取移动自组网中具有代表性的参考点群移动模型,基于ns2网络模拟平台,以参考点群组移动模型生成移动场景文件,应用层使用cbr数据流量,对OLSR无线路由协议在不同参数条件下的性能进行了模拟测试。通过对测试结果数据的详细分析,总结得出了OLSR无线路由协议在参考点群移动模型下端到端时延、报文交付率和路由负载三个方面的特点。为进一步研究移动自组网下基于OLSR协议的各种应用提供参考。     

Efficient Node Admission and Certificateless Secure Communication in Short-Lived MANETs

Decentralized node admission is an essential and fundamental security service in mobile ad hoc networks (MANETs). It is needed to securely cope with dynamic membership and topology as well as to bootstrap other important security primitives (such as key management) and services (such as secure routing) without the assistance of any centralized trusted authority. An ideal admission technique must involve minimal interaction among MANET nodes, since connectivity can be unstable. Also, since MANETs are often composed of weak or resource-limited devices, admission must be efficient in terms of computation and communication. Most previously proposed admission protocols are prohibitively expensive and require heavy interaction among MANET nodes. In this paper, we focus on a common type of MANET that is formed on a temporary basis, and present a secure, efficient, and a fully noninteractive admission technique geared for this type of a network. Our admission protocol is based on secret sharing techniques using bivariate polynomials. We also present a new scheme that allows any pair of MANET nodes to efficiently establish an on-the-fly secure communication channel.