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1.
基于节点接入能力的ad hoc网络按需路由协议   总被引:3,自引:0,他引:3  
官骏鸣  陆阳  盛锋  王俊伟 《通信学报》2007,28(10):32-37
基于802.11协议MAC层重传策略,提出一个衡量节点接入能力的参数CAM(capacity of access to medium),以体现节点周围信道的繁忙程度及其抢占信道能力。在此基础上,联合MAC层和网络层进行跨层设计,提出了一个拥塞感知路由CAOR(congestion aware on-demand routing)协议。仿真表明:该协议能够在降低开销的前提下,显著增加网络吞吐量,并降低平均端到端的时延。  相似文献   

2.
移动Ad hoc网络中,节点随机移动会引起通信链路频繁断开,从而导致路由失效,带来大量的路由重建与路由发现,耗费了有限的网络资源。传统按需路由中,采用简单的洪泛进行路由发现,路由请求包的盲目转发会带来大量不必要的冗余转发,造成广播风暴问题。此外,大量的数据包同时发送也会对彼此的传输造成干扰,增加数据包冲突概率。针对这种情况,本文提出一种基于干扰和连通度的路由协议,该协议结合节点的连通度和潜在干扰设计转发概率,不仅减少了路由请求包的传播范围,还减少了路由请求包的冲突概率,提高了传输成功率。仿真结果表明,本文设计的方案在减少路由开销的同时,有效提高了数据包投递率,从而提高了路由性能。  相似文献   

3.
采用方向性天线的ad hoc网络路由协议研究   总被引:1,自引:0,他引:1  
于全  吴克军 《通信学报》2008,29(8):69-76
为了降低方向性天线扫描路由发现的开销和代价,有效利用方向性天线的高空间复用度和高传输能力,提出一种采用方向性天线的ad hoc网络位置信息辅助的按需距离矢量路由协议DLAODV,协议以按需方式获取网络节点的位置信息,结合泛洪、受限泛洪、路由压缩、位置信息修正的贪婪转发策略以及分区桥接策略,充分利用方向性天线优势,有效提高路由发现效率,路由区分维护策略有效降低了路由维护开销.仿真结果显示,DLAODV能够使得网络获得高吞吐率、低时延和开销性能,相比采用全向天线的AODV协议性能获得了明显提升.  相似文献   

4.
肖阳  白磊  王仙 《通信学报》2015,36(Z1):203-214
从如何有效检测移动ad hoc网络路由入侵行为、如何准确地响应并将恶意路由节点移除网络,提供可信路由环境的角度进行分析,提出了一种基于朋友机制的轻量级移动ad hoc网络入侵检测模型,并以典型的黑洞攻击为例,通过OPNET网络建模仿真及实验分析,验证了该模型的可行性和有效性。  相似文献   

5.
利用多个信道接口来改善ad hoc网络信道容量。即一个信道周期性的广播节点状态信息分组来维护全网所有节点的状态信息,而另一个信道利用此信息采用最短路径搜寻算法来获得到目的节点的路由并完成数据传输。这样充分结合了表驱动路由方法和按需式路由方法的优点。另外,信息维护与数据分组分别在两个信道内同时进行,避免了信息维护对数据分组传输的影响,提高了网络性能。  相似文献   

6.
提出了一种基于能量消耗的路由切换模型(ERHM),它在路由维护中利用切换技术来使路由的能量消耗最小.仿真结果表明采用切换技术的ERHM模型的能量节省量要比不采用切换技术节约1.5~7.5倍,且节点的移动性越大,能量节约越多.  相似文献   

7.
基于BAN逻辑的ad hoc移动网络路由协议的安全性分析   总被引:2,自引:0,他引:2  
Ad hoe移动网络路由协议为加强其安全性,采用了密码技术,使其成为安全协议的一种。这使得采用形式化的方法分析其安全性成为可能。考虑ad hoe移动网络路由协议的特点,采用BAN逻辑对协议的安全性进行描述,提出了协议应满足的条件。并对协议的运行过程进行了形式化,给出具体的分析方法。采用该方法对安全路由协议SADSR进行了安全验证,说明方法的有效性。  相似文献   

8.
随着ad hoc网络的研究工作的发展,以Internet接入为代表的ad hoc网络的应用问题越来越被人们所关注.在本文中,我们提出了一个将ad hoc网络和移动IPv6相结合的方案,首先将基于动态源路由(dynamic source routing,DSR)的MANET升级到IPv6使其能够接入6Bone网,并通过搭建测试床进行了验证和测量;在此基础上,又提出了移动IPv6的兼容方案,并通过仿真对其在不同环境下的性能进行了验证.  相似文献   

9.
Adhoc网络是指由一组带有无线通信收发装置的移动节点组成的一个多跳、自组织、无中心网络。作为一个不需要固定基础设施特殊的无线网络,它在民用、军事与测量通信领域占据一席之地,成为当前网络研究的热点。本论文的主要研究目标是利用国内外现有的相关研究成果,对Adhoc自组网常用的AODV路由协议进行节能的研究,使其达到能耗低,长时间工作的目标,以应用在测试与监控中。最后通过仿真比较得以证明其改进的有效性。  相似文献   

10.
无线Ad hoc网络中基于拓扑的功率感知路由协议   总被引:2,自引:0,他引:2  
文凯  郭伟  黄广杰 《电子与信息学报》2008,30(12):3013-3017
无线Ad hoc网络中的节点通常是由电池提供能量,高效的节能策略在网络性能中具有非常重要的地位。为了降低网络能量的消耗,该文提出了一种TPR(Topology-based Power-aware Routing)协议。TPR协议主要利用无线传输中的多跳节能特性,通过建立节点的功率高效邻居集合,并用该集合去控制路由请求报文的转发过程,从而得以建立节能路由。计算机仿真验证表明,相比于现有的节能协议,TPR协议在获得较好节能效果的同时,并能在路由开销、路由发现时间、端到端时延等方面取得较好的均衡。  相似文献   

11.
A routing protocol for cognitive radio ad hoc networks (CRAHNs), namely, primary user supported routing (PSR) is demonstrated in this research. Unlike existing routing protocols for CRAHN, where routing of cognitive users (CUs) is accomplished within CUs, in this proposed protocol, some of the primary users (PUs) support CUs to communicate, by forwarding CU packets. This service provided by PU is of voluntary nature. However, such assistance shall be provided by the PUs, only when they are idle, thereby, preserving the principles of cognitive radio networks (CRNs), which indicates that the operation of PU should not be disturbed by the CU activities. The proposed work is compared with cognitive ad hoc on-demand distance vector (CAODV) protocol. The performance parameters considered are routing overhead, rate of loss of packets, and e2e packet delay. PSR outperforms CAODV in all these performance parameters. There has been on average 26.25% improvement in routing overhead, 34.12% decrease in loss, and 27.01% improvement in e2e delivery in the proposed PSR.  相似文献   

12.
The fundamental issues in mobile cognitive radio ad‐hoc networks are the selection of the optimal stable paths between nodes and proper assignment of the frequency channels/time slots (communication segments) to the links. In this paper, a joint load balanced stable routing and communication segment assignment algorithm is proposed that considers jointly the mobility prediction, mitigating the co‐channel interference and energy consumption. The novelty of the proposed algorithm lies in the increasing of the path stability, which benefits from the maximum link lifetime parameter and introduced weighting function to keep routes away from the PU's region. This avoids the negative impacts on the PUs' operations and decreases the conflict of the cognitive nodes. In the proposed algorithm, the concept of load balancing is considered that yields in the balancing energy consumption in the network, improving the network performance and distributing traffic loads on all available channels. The effectiveness of the proposed algorithm is verified by evaluating the aggregate interference energy, average end‐to‐end delay, goodput, and the energy usage per packet under 6 scenarios. The results show that the performance of the proposed algorithm is significantly better than the recently proposed joint stable routing and channel assignment protocol.  相似文献   

13.
研究ad hoc网络中无线链路存在邻近链路干扰及隐藏终端和暴露终端问题,提出新的带宽预留模型及带宽保证路由协议(BGRP),旨在按需探测符合带宽需要的路由路径并预留可靠的带宽资源。理论分析证明,BGRP探测的路由路径能满足带宽需要,而且预留的带宽资源准确有效。仿真结果表明,就有效带宽而言,BGRP较INSIGNIA和BGSR算法有效,而且消息复杂性较小,具有良好的网络扩展性。  相似文献   

14.
In this paper, we study the issue of routing in a vehicular ad hoc network with the assistance of sparsely deployed auxiliary relay nodes at some road intersections in a city. In such a network, vehicles keep moving, and relay nodes are static. The purpose of introducing auxiliary relay nodes is to reduce the end‐to‐end packet delivery delay. We propose a sparsely deployed relay node assisted routing (SRR) algorithm, which differs from existing routing protocols on how routing decisions are made at road intersections where static relay nodes are available such that relay nodes can temporarily buffer a data packet if the packet is expected to meet a vehicle leading to a better route with high probability in certain time than the current vehicles. We further calculate the joint probability for such a case to happen on the basis of the local vehicle traffic distribution and also the turning probability at an intersection. The detailed procedure of the protocol is presented. The SRR protocol is easy to implement and requires little extra routing information. Simulation results show that SRR can achieve high performance in terms of end‐to‐end packet delivery latency and delivery ratio when compared with existing protocols. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

15.
Recently, there has been an increasing interest in mobile ad hoc networks. In a mobile ad hoc network, each mobile node can freely move around and the network is dynamically constructed by collections of mobile nodes without using any existing network infrastructure. Compared to static networks, it faces many problems such as the inefficiency of routing algorithms. Also, the number of control packets in any routing algorithm increases as the mobile speed or the number of mobile nodes increases. Most of the current routing protocols in ad hoc networks broadcast the control packets to the entire network. Therefore, by reducing the number of control packets, the efficiency of the network routing will be improved. If we know where the destination is, we can beam our search toward that direction. However, without using global positioning systems, how can we do this? Define the range nodes as the 1‐hop or 2‐hop neighbors of the destination node. In this paper, we propose using the range nodes to direct our searches for the destination. It can be combined with the existing routing protocols to reduce the control overhead. We show through simulations that AODV and DSR combined with the range node method outperforms the original AODV and DSR routing protocols in terms of control packets overhead. We also show that the delay introduced in find range nodes is insignificant. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

16.
In the environment of scarce spectrum resources,cognitive ad hoc network which is independent with infrastruc-ture and fixed spectrum allocation policy,has been also developed quickly.Due to the characteristic of multi-channel routing,cognitive ad hoc network is commonly perceived as an environment offering both opportunities and threats.To further un-derstand the multi-channel routing threats,the current research situation and development trend,the types of threats were analyzed in terms of the node routing and the multi-channel selection,and several typical security methods were concluded.Meanwhile,the most important solution to keep the security of cognitive radio network was found to build trust relationship among cognitive users.Trust management was just the basic technology to solve the security problems of multi-channel routing.Finally,the current problems of related works and research trends in this area were discussed.  相似文献   

17.
In this paper, we develop a delay‐centric parallel multi‐path routing protocol for multi‐hop cognitive radio ad hoc networks. First, we analyze the end‐to‐end delay of multi‐path routing based on queueing theory and present a new dynamic traffic assignment scheme for multi‐path routing with the objective of minimizing end‐to‐end delay, considering both spectrum availability and link data rate. The problem is formulated as a convex problem and solved by a gradient‐based search method to obtain optimal traffic assignments. Furthermore, a heuristic decentralized traffic assignment scheme for multi‐path routing is presented. Then, based on the delay analysis and the 3D conflict graph that captures spectrum opportunity and interference among paths, we present a route discovery and selection scheme. Via extensive NS2‐based simulation, we show that the proposed protocol outperforms the benchmark protocols significantly and achieves the shortest end‐to‐end delay. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

18.
Mobile ad hoc networks (MANETs) are characterized by random, multi‐hop topologies that do not have a centralized coordinating entity or a fixed infrastructure that may change rapidly over time. In addition, mobile nodes operate with portable and finite power sources. In this work, we propose an energy‐efficient routing protocol for MANETs to minimize energy consumption and increase the network's consistency. Traditional works mainly focused on the shortest path‐based schemes to minimize energy, which might result into network failure because some nodes might exhaust fast as they are used repetitively, while some other nodes might not be used at all. This can lead to energy imbalance and to network life reduction. We propose an energy‐efficient ad hoc on‐demand routing protocol that balances energy load among nodes so that a minimum energy level is maintained among nodes and the network life increases. We focused on increasing the network longevity by distributing energy consumption in the network. We also compared the simulation results with a popular existing on‐demand routing protocol in this area, AODV, to establish the superiority of our approach. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

19.
In this paper, we discussed the issues of QoS multicast routing in cognitive radio ad hoc networks. The problem of our concern was: given a cognitive radio ad hoc network and a QoS multicast request, how to find a multicast tree so that the total bandwidth consumption of the multicast is minimized while the QoS requirements are met. We proposed two methods to solve it. One is a two‐phase method. In this method, we first employed a minimal spanning tree‐based algorithm to construct a multicast tree and then proposed a slot assignment algorithm to assign timeslots to the tree links such that the bandwidth consumption of the tree is minimized. The other is an integrated method that considers the multicast routing together with the slot assignment. Extensive simulations were conducted to show the performance of our proposed methods. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

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