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1.
该文提出了一种基于信道阻力的Ad hoc网络多路径动态源路由算法。算法中定义了信道阻力的概念,并以信道阻力为依据来进行多条路径的流量分配,由于信道阻力计算中综合考虑了链路质量的各个度量参数,因此能够根据各条路径的传输能力合理分配数据流量。NS2环境下的仿真表明,新算法能够有效地平衡网络负载,提高网络的吞吐量。  相似文献   

2.
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   

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.
无线ad hoc网络中多路径负载平衡性能分析   总被引:3,自引:1,他引:3  
王辉  俞能海 《通信学报》2005,26(11):30-39
提出了一种新颖的分析模型来计算无线ad hoc网络中多路径情况下的负载。该模型考虑到多路径的数目、路由的选取方法以及网络中节点的密度等条件,能够对不同网络条件下的负载进行较好的分析与理论计算。仿真结果与理论计算有良好的一致性,结果表明在无线ad hoc网络中简单地使用多路径路由并不能有效地平衡网络负载。这一结论与目前普遍认定的结论(在无线ad hoc网络中使用多路径路由和在有线网络中使用多路径路由一样,可以很好地平衡网络负载、增加网络的吞吐量)是不一致的。  相似文献   

5.
感知无线电技术作为一种新兴技术,通过时间和空间维度上的频谱空洞的利用能很好地提高频谱利用率。感知无线电的路由不同于传统的路由度量,因为次用户从时间和空间上都不能对主用户造成干扰。在感知无线电ad hoc网络环境下,选取了干扰作为路由的度量,并将干扰分为系统内干扰(次用户自身之间的干扰)和系统间干扰(次用户对主用户的干扰)。在已有的ad hoc网络干扰路由协议的基础上对干扰权重做出改进,并提出新的基于系统间路由干扰(对主用户干扰最小化)和基于联合系统内和系统间干扰的路由协议。仿真结果表明,该干扰模型符合感知无线电移动ad hoc网络的特性。  相似文献   

6.
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   

7.
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   

8.
ad hoc网络中基于蚁群系统算法(ACSA)的路由协议已经被广泛地研究,但其中的大部分本质上都属于单径路由协议,使得源宿之间最短路径上的主机负担加重。另一方面,由于引入了蚂蚁的正反馈机制,使得协议本身比较差的鲁棒性受到进一步的削弱,多径路由能够更好地支持QoS。本文将ACSA和链路不相交的多径路由结合起来以解决上述问题。新提出的基于ACSA的多径QoS路由方法建立和利用多条链路不相交路径来并发发送数据,并且采用信息素来分散通信流量,因此能够适应网络的动态变化和更好的支持QoS,仿真结果表明该方法要优于其他相关的算法。  相似文献   

9.
移动Adhoc网络的自组织、动态拓扑以及无线接入等特点使路由的安全性问题日益突出,而现有的Adhoc网络路由协议并没有提供安全的保护机制。论文首先论述了Adhoc网络几种常见的按需安全路由协议,指出有待解决的问题,在此基础上提出一种改进的、有效的安全路由协议(SEAR),阐述了该协议的路由请求、响应和维护的路由方式和过程,并通过协议间的比较分析其安全性和网络性能。该方案采用对称密钥协商和公钥认证方式,在兼顾性能资源的同时也保证了Adhoc网络的路由安全。  相似文献   

10.
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   

11.
Robust position-based routing for wireless ad hoc networks   总被引:1,自引:0,他引:1  
We consider a wireless ad hoc network composed of a set of wireless nodes distributed in a two dimensional plane. Several routing protocols based on the positions of the mobile hosts have been proposed in the literature. A typical assumption in these protocols is that all wireless nodes have uniform transmission regions modeled by unit disk centered at each wireless node. However, all these protocols are likely to fail if the transmission ranges of the mobile hosts vary due to natural or man-made obstacles or weather conditions. These protocols may fail because either some connections that are used by routing protocols do not exist, which effectively results in disconnecting the network, or the use of some connections causes livelocks. In this paper, we describe a robust routing protocol that tolerates up to roughly 40% of variation in the transmission ranges of the mobile hosts. More precisely, our protocol guarantees message delivery in a connected ad hoc network whenever the ratio of the maximum transmission range to the minimum transmission range is at most .  相似文献   

12.
In this paper, we address the problem of broadcast routing in mobile ad hoc networks from the viewpoint of energy efficiency. In an ad hoc wireless network, each node runs on a local energy source which has a limited energy lifespan. Thus, energy conservation is a critical issue in ad hoc networks. One approach for energy conservation is to establish routes which require lowest total energy consumption. This optimization problem is referred as the minimum‐energy broadcast routing problem (MEBRP). In this paper, we propose new efficient algorithms for the construction of energy‐efficient trees for broadcast in mobile ad hoc networks. These algorithms exploit the broadcast nature of the wireless channel, and address the need for energy‐efficient operations. Empirical studies show that our algorithms are able to achieve better performance than algorithms that have been developed for MEBRP. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

13.
According to the disadvantages of real time and continuity for multimedia services in ad hoc networks, a delay constraint multipath routing protocol for wireless multimedia ad hoc networks, which can satisfy quality of service (QoS) requirement (QoS multipath optimized link state routing [MOLSR]), is proposed. The protocol firstly detects and analyzes the link delay among the nodes and collects the delay information as the routing metric by HELLO message and topology control message. Then, through using the improved multipath Dijkstra algorithm for path selection, the protocol can gain the minimum delay path from the source node to the other nodes. Finally, when the route is launched, several node‐disjoint or link‐disjoint multipaths will be built through the route computation. The simulation and test results show that QoS‐MOLSR is suitable for large and dense networks with heavy traffic. It can improve the real time and reliability for multimedia transmission in wireless multimedia ad hoc networks. The average end‐to‐end delay of QoS‐MOLSR is four times less than the optimized link state routing. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

14.
SMORT: Scalable multipath on-demand routing for mobile ad hoc networks   总被引:3,自引:0,他引:3  
L.  S.V.   《Ad hoc Networks》2007,5(2):162-188
Increasing popularity and availability of portable wireless devices, which constitute mobile ad hoc networks, calls for scalable ad hoc routing protocols. On-demand routing protocols adapt well with dynamic topologies of ad hoc networks, because of their lower control overhead and quick response to route breaks. But, as the size of the network increases, these protocols cease to perform due to large routing overhead generated while repairing route breaks. We propose a multipath on-demand routing protocol (SMORT), which reduces the routing overhead incurred in recovering from route breaks, by using secondary paths. SMORT computes fail-safe multiple paths, which provide all the intermediate nodes on the primary path with multiple routes (if exists) to destination. Exhaustive simulations using GloMoSim with large networks (2000 nodes) confirm that SMORT is scalable, and performs better even at higher mobility and traffic loads, when compared to the disjoint multipath routing protocol (DMRP) and ad hoc on-demand distance vector (AODV) routing protocol.  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.
We consider the problem of localized energy aware routing in mobile ad hoc networks. In localized routing algorithms, each node forwards a message based on the position of itself, its neighbors and the destination. The objective of energy aware routing algorithms is to minimize the total power for routing a message from source to destination or to maximize the total number of routing tasks that a node can perform before its battery power depletes. In this paper we propose new localized energy aware routing algorithms called OLEAR. The algorithms have very high packet delivery rate with low packet forwarding and battery power consumption. In addition, they ensure good energy distribution among the nodes. Finally, packets reach the destination using smaller number of hops. All these properties make our algorithm suitable for routing in any energy constrained environment. We compare the performance of our algorithms with other existing energy and non‐energy aware localized algorithms. Simulation experiments show that our algorithms present comparable energy consumption and distribution to other energy aware algorithms and better packet delivery rate. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

17.
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   

18.
适合ad hoc网络无需安全信道的密钥管理方案   总被引:4,自引:0,他引:4  
密钥管理问题是构建ad hoc安全网络系统首要解决的关键问题之一.针对ad hoc网络特点,提出了一个无需安全信道的门限密钥管理方案.该方案中,可信中心的功能由局部注册中心和分布式密钥生成中心共同实现,避免了单点失效问题;通过门限技术,网络内部成员相互协作分布式地生成系统密钥;利用基于双线性对的公钥体制实现了用户和分布式密钥生成中心的双向认证;通过对用户私钥信息进行盲签名防止攻击者获取私钥信息,从而可以在公开信道上安全传输.分析表明该方案达到了第Ⅲ级信任,具有良好的容错性,并能抵御网络中的主动和被动攻击,在满足ad hoc网络安全需求的情况下,极大地降低了计算和存储开销.  相似文献   

19.
In this paper, we design a localized power‐aware alternate routing (LPAR) protocol for dynamic wireless ad hoc networks. The design objective is to prolong the lifetime of wireless ad hoc networks wherein nodes can adaptively adjust their transmission power based on communication ranges. LPAR achieves this goal via two phases. In the first phase, energy draining balancing is achieved by identifying end‐to‐end paths with high residual energy. The second phase is designed to effectively reduce the power consumed for packet forwarding. This is achieved by iteratively performing adaptive localized power‐aware alternate rerouting to bypass each (potentially) high‐power link along the end‐to‐end path identified in the first phase. Further, the design of LPAR enables nodes to collect their neighborhood information ‘on‐demand’, which can effectively reduce the overhead for gathering such information. LPAR is suitable for both homogeneous and non‐homogeneous networks. Simulation results demonstrate that LPAR achieves improved performance in reducing protocol overhead and also in prolonging network lifetime as compared with existing work. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

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