Ad Hoc无线网络及其路由选择协议

AdHoc无线网络是一组无线移动主机组成的一个没有任务建立好的基础调和或集中管理设备的临时网络。文中介绍了adhoc无线网络的特点和设计，并根据表驱动和按需路由两大类重点介绍了adhoc无线网络的路由选择协议。     

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。     

MANET中一种基于移动预测的unicast路由协议

MANET是由一系列可以自由移动的节点主机聚集而成的一个临时性动态网络。它没有固定基站,也没有作为控制管理中心的节点主机。由于其拓扑的动态性,其路由协议不同于其它网络。为更有效支持MANET的应用,文章提出了一种基于移动预测下的Unicast路由。该协议采用GPS定位机制,通过预测路径有效连接时间来实现。模拟结果表明这种方案能获得较好的网络性能和较低的控制开销。     

Ad Hoc网络多路径需求路由及路径熵选择算法

无线移动Ad Hoc网络是一种不依赖任何固定基础设施的移动无线多跳网络.由于其动态性和资源的限制,在Ad Hoc网络中提供多路径路由是一个重要的研究课题.描述了一种Ad Hoc网络中基于信息熵选择的稳定多路径路由算法(stability multipath on-demand routing,简称SMDR),提出了路径熵的度量参数,并利用路径熵来选择稳定的、长寿命的多路径,减少了重构路由的次数,从而在网络拓扑频繁变化的Ad Hoc网络环境中较好地提供QoS保证和提高数据传输率.仿真结果表明,SMDR协议改进了分组传输率、端到端时延和路由负载率.SMDR协议为解决动态的Ad Hoc网络多路径传输提供了一种新的有效途径.     

Ad Hoc网络安全

Ad Hoc网络是针对移动主机提出的一种新型无线网络范例，与传统的移动无线网络不同，它不依赖任何固定设备。设计这种网络的一项主要挑战就是抵抗攻击的脆弱性。在这篇文章中，我们主要研究Ad Hoc网络所面临的威胁以及要达到的安全目标。我们找出这种新型网络环境下面临的新的挑战，并设计出新的方法以保证网络的正常通信。进一步地说，我们利用Ad Hoc网络内在的冗余(节点之间存在多条路线)来防止攻击。     

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 stability-based distributed routing mechanism to support unicast and multicast routing in ad hoc wireless network

An ad hoc network can be envisioned as a collection of mobile routers, each equipped with a wireless transceiver, which are free to move about arbitrarily. In ad hoc wireless networks, even if two nodes are outside the wireless transmission range of each other, they may still be able to communicate in multiple hops using other intermediate nodes. However, the dynamics of these networks, as a consequence of mobility and disconnection of mobile hosts, pose a number of problems in designing routing schemes for effective communication between any pair of source and destination. In this paper, a stability-based unicast routing mechanism, that considers both link affinity and path stability in order to find out a stable route from source to destination, is proposed. It is then extended to support multicast routing as well where only local state information (at source) is utilized for constructing a multicast tree. The performance of the proposed scheme is evaluated on a simulated environment to show that the stability-based scheme provides a unified framework for both unicast and multicast routing and reduces the probability of route error drastically in both the cases.     

Inter-Cluster Routing Authentication for Ad Hoc Networks by a Hierarchical Key Scheme

Dissimilar to traditional networks, the features of mobile wireless devices that can actively form a network without any infrastructure mean that mobile ad hoc networks frequently display partition due to node mobility or link failures. These indicate that an ad hoc network is difficult to provide ou-llne access to a trusted authority server. Therefore, applying traditional Public Key Infrastructure （PKI） security framework to mobile ad hoc networks will cause insecurities. This study proposes a scalable and elastic key management scheme integrated into Cluster Based Secure Routing Protocol （CBSRP） to enhance security and non-repudiation of routing authentication, and introduces an ID-Based internal routing authentication scheme to enhance the routing performance in an internal cluster. Additionally, a method of performing routing authentication between internal and external clusters, as well as inter-cluster routing authentication, is developed. The proposed cluster-based key management scheme distributes trust to an aggregation of cluster heads using a threshold scheme faculty, provides Certificate Authority （CA） with a fault tolerance mechanism to prevent a single point of compromise or failure, and saves CA large repositories from maintaining member certificates, making ad hoc networks robust to malicious behaviors and suitable for numerous mobile devices.     

一种稳定的按需QoS路由协议

一个ad hoc网络是一个多跳无线网络,网络中的节点互相通信而不依赖于预先架设的固定基础设施，选路协议中的频繁的路由失败和高控制开销致使系统性能降低.本文提出了一个稳定的分布式Ad hoc路由协议，该协议支持QoS选路用于多媒体应用．     

A cost matrix agent for shortest path routing in ad hoc networks

Wireless ad hoc networks do not rely on an existing infrastructure. They are organized as a network with nodes that act as hosts and routers to treat packets. With their frequent changes in topology, ad hoc networks do not rely on the same routing methods as for pre-established wired networks; they require routing methods for mobile wireless networks. To select a path from a source to a destination in dynamic ad hoc networks, an efficient and reliable routing method is very important. In this paper, we introduce a cost-matrix-based routing algorithm. An agent node creates topology information in the form of the adjacency-cost matrix which shows link costs of the network.Based on the adjacency-cost matrix, the minimum-cost matrix and the next-node matrices can be calculated. Based on the minimum-cost matrix and the next-node matrices, the minimum cost between source and destination nodes and between intermediate nodes on the minimum-cost paths can be calculated.The matrices are periodically distributed by the agent to the other nodes. Based on the minimum-cost matrix and the next-node matrices, each node decides the minimum-cost path to its destination. Because none of the nodes except the agent needs to gather network topology information, the control overhead of the proposed method is small compared with those of the general table-driven routing protocols.     

无线Ad Hoc网络QoS路由协议研究的进展与展望

无线ad hoc网络是一种无固定通信设备支持、节点可自由移动的多跳全分布式无线网络。无线ad hoc网络的应用环境以及与Internet的互连要求它必须提供一定的服务质量(QoS)保证,而QoS路由协议是无线ad hoc网络支持QoS的一个关键理论和技术,也是目前的一个研究热点。本文回顾了近年来国内外在无线ad hoc网络QoS路由协议研究方面取得的研究成果,对已有的无线ad hoc网络的QoS路由协议进行了分类．并对它们作了较全面的概括。总结和深入的比较分析,系统阐述了在无线ad hoc网络中实现QoS路由协议时需要考虑的因素,指出了亟待解决的问题和今后的研究方向。     

Secure communications for cluster-based ad hoc networks using node identities

Ad hoc networks are self-configurable networks with dynamic topologies. All involved nodes in the network share the responsibility for routing, access, and communications. The mobile ad hoc network can be considered as a short-lived collection of mobile nodes communicating with each other. Such networks are more vulnerable to security threats than traditional wireless networks because of the absence of the fixed infrastructure. For providing secure communications in such networks, lots of mechanisms have been proposed since the early 1990s, which also have to deal with the limitations of the mobile ad hoc networks, including high power saving and low bandwidth. Besides, public key infrastructure (PKI) is a well-known method for providing confidential communications in mobile ad hoc networks. In 2004, Varadharajan et al. proposed a secure communication scheme for cluster-based ad hoc networks based on PKI. Since the computation overheads of the PKI cryptosystem are heavy for each involved communicating node in the cluster, we propose an ID-based version for providing secure communications in ad hoc networks. Without adopting PKI cryptosystems, computation overheads of involved nodes in our scheme can be reduced by 25% at least.     

F-Ant: an effective routing protocol for ant colony optimization based on fuzzy logic in vehicular ad hoc networks

Vehicular ad hoc networks (VANETs) are a subset of mobile ad hoc networks that provide communication services between nearby vehicles and also between vehicles and roadside infrastructure. These networks improve road safety and accident prevention and provide entertainment for passengers of vehicles. Due to the characteristics of VANET such as self-organization, dynamic nature and fast-moving vehicles, routing in this network is a considerable challenge. Swarm intelligence algorithms (nature-inspired) such as ant colony optimization (ACO) have been proposed for developing routing protocols in VANETs. In this paper, we propose an enhanced framework for ACO protocol based on fuzzy logic for VANETs. To indicate the effectiveness and performance of our proposed protocol, the network simulator NS-2 is used for simulation. The simulation results demonstrate that our proposed protocol achieves high data packet delivery ratio and low end-to-end delay compared to traditional routing algorithms such as ACO and ad hoc on-demand distance vector (AODV).

     

Transmission of layered video streaming via multi-path on ad hoc networks

Mobile ad hoc networks without centralized infrastructure change their topology rapidly because of node mobility, making multimedia applications difficult to run across wireless networks. Moreover, video transmission over ad hoc networks causes frequent transmission loss of video packets owing to end-to-end transmission with a number of wireless links, and requires essential bandwidth and restricted delay to provide quality-guaranteed display. This paper presents an architecture supporting transmission of multiple video streams in ad hoc networks by establishing multiple routing paths to provide extra video coding and transport schemes. This study also proposes an on-demand multicast routing protocol to transport layered video streams. The multicast routing protocol transmits layered video streaming based on a weight criterion, which is derived according to the number of receivers, delay and expiration time of a route. A simulation is performed herein to indicate the viability and performance of the proposed approach. The simulation results demonstrate that the proposed transport scheme is more effective than other video transport schemes with single or multiple paths.

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.     

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.     

动态源路由协议(DSR)在Linux下的实现

动态源路由协议(DynamicSourceRoutingProtocol,DSR)是由移动节点组成的多跳无线AdHoc网络犤3,4犦中一种简单和行之有效的路由协议犤1犦。协议允许任一结点动态发现到达AdHoc网络中其它任意节点的路由,所有的路由信息由DSR自动地进行维护。每个DSR头部都携带了到达目的节点的完整的路由跃点列表(hoplist),中间节点只需简单地对分组进行转发即可。同时DSR协议完全按需(on-demand)的特性可以显著减少路由协议的开销,节省了电池能量,减少了分组冲突的概率并减少了潜在的大规模的路径更新信息的传播。使用DSR协议可以实现AdHoc网络的完全的自组织和自配置而无需任何已经存在的网络基础设施。论文详细论述了DSR路由协议在Linux操作系统下借助Netfilter的实现。     

A survey of secure wireless ad hoc routing

Ad hoc networks use mobile nodes to enable communication outside wireless transmission range. Attacks on ad hoc network routing protocols disrupt network performance and reliability. The article reviews attacks on ad hoc networks and discusses current approaches for establishing cryptographic keys in ad hoc networks. We describe the state of research in secure ad hoc routing protocols and its research challenges.     

Intrusion detection for secure clustering and routing in Mobile Multi-hop Wireless Networks

Intrusion detection and secure routing schemes have been proposed for increasing security and reliability in critical wireless scenarios. In this paper we present an integrated secure routing system based on Intrusion Detection Systems (IDS) and Statistically Unique and Cryptographically Verifiable (SUCV) identifiers. The proposed IDS has been used for the support of secure Ad Hoc On Demand Distance Vector (AODV) routing, named IDS-based Secure AODV (IS-AODV), in wireless ad hoc and vehicular network scenarios. Our IDS is based on the detection of behavior anomalies on behalf of neighbor hosts, with passive reactions, aiming to create a cluster whose route paths will include only safe nodes, eventually. Simulation results show that the proposed IDS is effective in isolating misbehaving hosts, and it assists the AODV secure routing scheme to converge in finding safe end-to-end routes.     

移动Ad hoc网络路由协议的研究——一种基于AODV路由协议的改进算法

Adhoc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，网络不依赖于建设好的基础组织。在Adhoc网络的研究中．一个非常重要的领域是路由问题，因为每个节点兼具主机和路由器的功能，这样就需要适合Adhoe这种特殊环境的路由协议和路由算法。本文探讨了一种基于AODV路由协议（Adhoe On-demand Distant Vector，按需距离矢量路由算法）的改进算法——按需距离矢量多径路由算（AODVM算法），并对其性能进行了简单仿真分析，对研究可靠多径路由有一定的指导意义。