基于地理信息系统的路由协议研究

针对车辆自组织网络提出了基于地理信息系统的路由协议GBRP,以此来解决节点高速移动而引起的路径重建问题.由于利用了地理信息系统中提取的道路空间信息,该协议可以规避城市环境下车辆自组织网络中存在的固定的或者暂时的拓扑空洞问题.仿真实验结果表明新的路由协议与DSR相比有较高的分组传输率,较低的路由开销,协议扩展性更好,更适合于城市环境下的车载通信.     

无线Ad hoc网络机会路由的实现与仿真

在无线自组织网络中,路由协议对网络的性能起着关键性作用。然而由于无线信道的不稳定性经常造成通信中断而需重建路由,使自组织网传统路由协议的效率大大降低。提出了一种应用于无线自组织网络的机会路由协议（WAOR）,利用无线信道的广播特性和多径传输来增强链路的可靠性。采用网络仿真器NS2的仿真结果表明,WAOR的性能优于传统的动态源路由协议（DSR）和自组织网按需平面距离矢量路由协议（AODV）。     

关于车载自组织网络路由协议的探析研究

随着信息技术信息网络化构建越来越频繁,车辆与车辆或者是车辆与路边通信站之间的有效联系,车载自组织网络也开始得到发展。从现实效应来看,车载自组织网络的出现,极大地方便了车辆间和车辆与道路通信站之间的联系,具有非常强的现实意义。为了提高该技术的利用效率,强化车载自组织网络路由协议分析具有重要的价值。本文就车载自组织网络路由协议进行分析,旨在深化技术研究,提高技术利用率。     

车载自组织网络路由协议的探析

随着信息技术和网络技术的不断发展,现代社会的信息网络化构建越来越频繁,为了实现车辆与车辆或者是车辆与路边通信站之间的有效联系,车载自组织网络也开始得到发展。从现实效应来看,车载自组织网络的出现,极大地方便了车辆间和车辆与道路通信站之间的联系,具有非常强的现实意义。为了将这种技术进行推广,也为了提高此类技术的利用效率,强化车载自组织网络路由协议的分析具有重要的价值。本文就车载自组织网络路由协议进行分析,旨在深化技术研究,提高技术利用率。     

无线自组织网络中的路由技术研究

路由技术是无线自组织网络组网的基础和关键环节.文章介绍了当前无线自组织网络路由技术研究的现状,在此基础上,详述了无线自组织网络中具有代表性的路由协议,并对这一领域未来的发展趋势作了展望.     

车载自组织网络路由协议研究进展与比较

车载自组织网络( VANET)是一种新型移动自组织网络。作为移动无线网络的热点研究领域,车载自组织网络的间歇连通性使路由设计充满挑战。首先阐述了车载自组织网络的主要特征和应用;在对车载网络路由协议进行分类的基础上,详细描述了一批有代表性的路由协议;对比和总结了各类路由协议的特点,并提出相关研究建议,可为车载网络路由协议研究提供一定的参考价值。     

车载自组织网络路由协议研究进展与比较

车载自组织网络（VANET）是一种新型移动自组织网络。作为移动无线网络的热点研究领域,车载自组织网络的间歇连通性使路由设计充满挑战。首先阐述了车载自组织网络的主要特征和应用;在对车载网络路由协议进行分类的基础上,详细描述了一批有代表性的路由协议;对比和总结了各类路由协议的特点,并提出相关研究建议,可为车载网络路由协议研究提供一定的参考价值。     

无线自组织网络的路由选择研究

本文简述了无线自组织网络的主要特征,详细介绍了自组织网络常用的路由协议,对一种实用自组织网络的路由选择进行了分析研究,并给出了针对该实用自组织网络中不同类型的通信链路所采用的路由协议及相应的路由选择算法。     

无线传感器网络路由协议研究分析

无线传感器网络与传统网络不同,有其自身的特殊性,不能采用传统的路由方式.分析了无线传感器网络的特点,重点阐述无线传感器网络中有代表性的路由协议,并分析各种协议的优缺点.通过详细比较各种协议,总结无线传感器网络现有路由协议存在的问题,并展望无线传感器网络路由协议未来的研究方向和发展趋势.     

城市场景下基于速度信息的VANET路由协议的改进

车载自组网络(Vehicular Ad Hoc Networks,VANET)是指道路上由车辆搭载的无线通信装置构成的一种特殊的多跳无线移动自组织网络。VANET在实现多种智能交通方面应用的同时,还能满足用户在乘车时的娱乐等舒适性的需求,近些年来已成为无线自组网络研究的新热点。总结了近些年来出现的主要VANET路由协议的核心路由机制及其优缺点,并分析了各种技术对路由协议性能的影响。其后给出了一种基于速度信息的VANET路由协议改进方法,并通过实验验证了将改进方法与GPSR协议结合可以提高路由路径的稳定性,减少了端到端的平均时延,降低了VANET网络中拓扑的高动态性对路由协议性能的影响。     

Self‐adaptive routing protocols for integrating cellular networks,WLANs, and MANETs

A growing need to have ubiquitous connectivity has motivated our research to provide continuous connection between various wireless platforms such as cellular networks, wireless local area networks (WLANs), and mobile ad hoc networks (MANETs). In this paper, we consider integration at the routing layer and propose two adaptable routing protocols (IRP‐RD and IRP‐PD) that exploit topology information stored at the fixed network components (cellular base stations and WLAN access points) for the route discovery and maintenance processes. Our proposed protocols can provide connectivity to the cellular network and/or WLAN hotspots through multihop routing, while differ in the gateway discovery approach used. In IRP‐RD, multihop routes to gateways to the cellular network or WLAN hot spots are discovered on demand, while in IRP‐PD out of coverage users proactively maintain routes to the gateways. Furthermore, proposed protocols can be used in any heterogeneous scenario, combining a cellular network and WLANs operating in infrastructure or ad hoc (MANET) mode. We provide simulation results that demonstrate the effectiveness of the proposed integrated routing protocols and show the advantages and drawbacks of each gateway discovery approach in different heterogeneous scenarios. Copyright © 2006 John Wiley & Sons, Ltd.     

QoS routing based on multi-class nodes for mobile ad hoc networks

In this paper, we present a new quality of service (QoS) routing protocol for mobile ad hoc networks (MANETs). Most of the existing routing protocols assume homogeneous nodes in MANETs, i.e., all nodes have the same communication capabilities and characteristics. However, in many ad hoc networks, nodes are not the same. Some nodes have longer transmission range, larger transmission bandwidth, and are more reliable and robust than other nodes. We take advantage of the non-homogeneous property to design more efficient QoS routing protocol. And node location information is used to aid routing. We also develop a new algorithm to calculate end-to-end bandwidth for a given path. Our QoS routing protocol contains end-to-end bandwidth calculation and bandwidth reservation. QoS route is discovered and setup only when it is needed. Extensive simulation studies demonstrate the good performance of the QoS routing protocol.     

Joint Design of Routing and Medium Access Control for Hybrid Mobile Ad Hoc Networks

Efficient routing and medium access control (MAC) are very important for Mobile Ad hoc Networks (MANETs). Most existing routing and MAC protocols consider homogeneous ad hoc networks, in which all nodes are modeled as the same, i.e., they have the same communication capabilities and characteristics. Although a homogeneous network model is simple and easy to analyze, it misses important characteristics of many realistic MANETs such as military battlefield ad hoc networks. In addition, a homogeneous ad hoc network suffers from poor performance and scalability. In many ad hoc networks, multiple types of nodes do co-exist; and some nodes have larger transmission power, higher transmission data rate, and better processing capability, are more reliable and robust than other nodes. Hence, a hybrid network model is more realistic and provides many advantages for designing better routing and MAC protocols. In this paper, we present a new routing protocol called Hybrid Routing, which is specifically designed for hybrid MANETs. In addition, a novel MAC protocol is jointly designed for hybrid MANETs. Extensive simulations demonstrate that the proposed routing MAC protocols have very good performance.

移动Ad hoc网络可靠多路径路由协议的综述

分析研究了移动Adhoc网络（MANET）的可靠多路径路由协议,可靠多路径路由协议的主要目标是提供可靠的通信、以确保负载平衡以及提高服务质量（QoS）。本文分析了Adhoc网络多路径路由技术的研究进展,论述了典型的Adhoc网络多路径路由协议性能,最后对Adhoc网络多路径路由的发展趋势进行了展望。     

POSITION VERIFICATION APPROACHES FOR VEHICULAR AD HOC NETWORKS

Intervehicle communication is regarded as one of the major applications of mobile ad hoc networks (MANETs). Compared to MANETs, these so-called vehicular ad hoc networks (VANETs) have special requirements in terms of node mobility and position-dependent applications, which are well met by geographic routing protocols. Functional research on geographic routing has already reached a considerable level, whereas security aspects have been vastly neglected so far. Since position dissemination is crucial for geographic routing, forged position information has severe impact regarding both performance and security. In this work, we first analyze the problems that may arise from falsified position data. Then, in order to lessen these problems, we propose detection mechanisms that are capable of recognizing nodes cheating about their location in position beacons. In contrast to other position verification approaches, our solution does not rely on special hardware or dedicated infrastructure. Evaluation based on simulations shows that our position verification system successfully discloses nodes disseminating false positions and thereby widely prevents attacks using position cheating     

A survey and qualitative analysis of mac protocols for vehicular ad hoc networks

In order to avoid transmission collisions in mobile ad hoc networks (MANETs), a reliable and efficient medium access control (MAC) protocol is needed. Vehicular MANETs (VANETs) have vehicles as network nodes and their main characteristics are high mobility and speed. Active safety applications for VANETs need to establish reliable communications with minimal transmission collisions. Only few MAC protocols designed for MANETs can be adapted to efficiently work in VANETs. In this article we provide a short overview on some MANET MAC protocols, and then we summarize and qualitatively compare the ones suited for VANETs     

Adaptive fuzzy multiple attribute decision routing in VANETs

Vehicular ad hoc networks (VANETs) have attracted much research attentions in the recent years. Although there are many outstanding solutions of geographic routing designed for the VANETs, only one or two features of the VANETs have been specifically utilized in each of the proposed solutions. In this paper, we propose a novel adaptive fuzzy multiple attribute decision routing (AFMADR) scheme, by which a packet carrier is supposed to be a decision maker in the selection of a target for the next hop transmission with more factors to be considered. The AFMADR scheme consists of four steps. Firstly, the candidate vehicles are characterized by four attributes including the distance, the direction, the road density, and the location to obtain a fuzzy attribute score of each attribute. Secondly, according to the real‐time conditions of the candidates' attributes, weights of attributes will be calculated by the proposed adaptive weight algorithm, which makes the AFMADR scheme more scalable and robust in different VANET scenarios. Then, a fuzzy performance score will be produced for each candidate based on the fuzzy attribute score and their real‐time weights. Lastly, a route decision is made by choosing a candidate with the highest performance score as the target for the next hop transmission. We carry out simulation experiments to compare the performance of the AFMADR scheme with the existing well‐known geographic routing protocols for the VANETs. The simulation results demonstrate that the proposed AFMADR scheme can achieve the best performance in terms of the highest delivery ratio and the lowest delivery delay with a reasonable number of hops among all protocols in all the simulation scenarios. Copyright © 2015 John Wiley & Sons, Ltd.     

Performance of ad hoc routing using directional antennas

This paper evaluates the tradeoffs involved in using directional antennas in ad hoc routing. Although problems with utilizing directional antennas have been visited in the past, the research has been confined mostly to medium access control. To determine whether directional antennas are beneficial to ad hoc networks, it is necessary to evaluate the impact of directional antennas on the performance of routing protocols as well. In this paper, we evaluate the performance of DSR (dynamic source routing) using directional antennas. We identify several issues that emerge from executing DSR (originally designed for omnidirectional antennas) over directional antennas. Using insights gained from simulations, we propose routing strategies that adapt the routing protocol to directional communication. Our analysis shows that by using directional antennas, ad hoc networks may achieve better performance. However, scenarios exist in which using omnidirectional antennas may be more appropriate.     

车载自组织网络中基于贪婪算法能地理位置路由

车载自组织网络（VANET）技术发展迅速,但由于其特殊的节点类型和信道特性,采用传统AdHoc网络路由协议无法取得满意的性能。实现高速可靠的数据传输速率,需要研究新兴的路由算法。基于贪婪算法的地理位置辅助路由是目前VANET路由的主流思路。文章认为基于这类思路的协议利用车载GPS装置、电子地图和下一代网络导航技术,能使路由发现和建立的时间大大缩短;结合已知的道路拓扑结构,选择多跳传输的最优路径,能避免路边建筑物的屏蔽效应,改善信道条件;动态评估道路上的车流密度,选择可靠性最高的传输路径,能很好地降低传输时延,提高网络吞吐能力。