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1.
Bluetooth is one of the most widespread technologies for personal area networks that allow portable devices to form multi-hop Bluetooth ad hoc networks, so called scatternets. Routing is one of the challenges in scatternets because of its impact on the performance of the network. It should focus on reducing the power consumption in the network because most of the nodes are battery-operated portable devices. In this paper, we propose a routing protocol for Bluetooth scatternets that customizes the Ad hoc On-Demand Distance Vector (AODV) routing protocol by making it power-aware and suitable for scatternets. It enhances the AODV flooding mechanism by excluding all non-bridge slaves from taking apart in the AODV route discovery process. In addition, it improves the AODV route discovery phase by considering the hop count, the predicated node’s power, and the average traffic intensity for each node as metrics for best route selection. By removing HELLO packets, our protocol reduces the control packets overhead and the power consumption in network devices. Simulation results show that the proposed protocol achieved considerable improvements over other enhanced AODV protocols by increasing the data delivery ratio by 10.78%, reducing the average end-to-end delay by 8.11%, and reducing the average energy consumption by 7.92%.  相似文献   

2.
移动自组网路由局部修复算法的研究   总被引:5,自引:0,他引:5  
移动自组织网(mobile ad hoc networks,MANET)的多跳的无线连接、动态拓扑和有限的带宽等特征,给其路由协议带来了很多挑战.当多跳路径失效时,路由协议需要对其进行修复.已有的修复机制需要很多的开销和很长的端到端时延.在此修复机制的基础上,提出了一种新的路由局部修复算法,将修复尽量限制在断链的局部范围内,以减少对链路断裂的反应时间和降低路由维护的开销,而且不用考虑失效链路在整个路由上的相对位置,都可以对其进行修复,提高了处理失效链路的能力,有利于提高MANET的可扩展性.仿真表明,这种新的路由局部修复算法明显地提高了网络多方面的性能.  相似文献   

3.
Routing protocols for Mobile ad hoc networks (MANETs) have been studied extensively in the past decade. Routing protocols for MANETs can be broadly classified as reactive (on-demand), proactive, hybrid and position-based. Reactive routing protocols are attractive because a route between a source and a destination is established only when it is needed. Such protocols, unlike proactive protocols, do not have high overhead for route maintenance and are especially suitable for networks in which not all nodes communicate frequently. One problem with existing reactive routing protocols is the propagation of redundant route request messages during route discovery. In this paper, we present a low-overhead reactive routing protocol which reduces propagation of redundant route request messages. We also compare its performance with the well-known reactive routing protocol AODV.  相似文献   

4.
基于位置信息的改进AODV路由算法   总被引:2,自引:0,他引:2  
针对AODV协议路由开销较大的问题,提出一种基于位置信息的改进路由协议(GAODV).GAODV利用中间节点重新计算转发角度,保证转发角度内邻居节点数不小于预设门限值,同时还引入基于位置信息的计数器方案,使距离目的节点近的中间节点优先转发路由请求消息,有利于减少转发冗余路由请求信息和降低寻路失败概率.OPNET仿真实验结果表明,GAODV在数据分组投递率、路由开销、总丢包数、端到端时延和平均路由跳数等方面都优于已有算法.  相似文献   

5.
按需式ad hoc移动网络路由协议的研究进展   总被引:23,自引:1,他引:23  
臧婉瑜  于勐  谢立  孙钟秀 《计算机学报》2002,25(10):1009-1017
Ad hoc移动网络是一种完全由移动主机构成的网络,网络拓扑易变,带宽,能源有限是ad hoc移动网络的主要特点,针对这些特点,目前设计的ad hoc路由协议大多采用按需查找方式,该文介绍了这方面研究的最新进展,对几种典型的按需路由协议进行了说明,分析和综合比较,文中分析了目前协议存在的一些问题并提出了相应的改进方法,最后指出了下一步研究方向。  相似文献   

6.
一种累计多路径的移动自组网络路由策略   总被引:14,自引:3,他引:14       下载免费PDF全文
描述了一种基于多路径移动自组网络按需路由策略.在移动自组网络,由于网络节点的移动性及拓扑结构的易变性,路由成为最受关注的问题.在以前的移动自组网络路由算法中,主要采用的是传统的单路径方式.最近,多路径方式也逐渐出现,因为相对单路径路由而言,多路径为移动自组网络提供的QoS支持更可行、更高效.鉴于现有的移动自组网络多路径策略未能为源节点提供充分的信息,提出了一种新型的移动自组网络多路径路由算法.该算法可以将路由信息保存在源节点中,并依此在源节点中采用替换路径或多路径并发的方式进行数据传输.  相似文献   

7.
为了延长无线传感器网络的生命周期,进行了无线传感器网络中节能路由协议的探索性研究,提出了一种新的节能路由协议并将其具体实现.首先分析了传感器网络应用的特点以及设计和应用中的限制,综述了现有传感器网络中节能路由设计的方法,设计并实现了一种基于能量的半径自适应路由协议ERARP;然后在OPNET仿真平台上对该协议进行了仿真模拟;最后与无线传感器网络传统的两种节能路由协议基于信息协商的传感器网络协议和直接扩散协议在同等条件下针对节点能量使用、延迟、丢包率和吞吐量等四个性能评价指标进行了对比.结果表明,ERARP使得节点能够根据自身剩余能量的状况对节点的运行模式进行控制,同时对无线模块的收发半径进行动态调整,达到节能目的.  相似文献   

8.
能量捕获无线传感器网络是无源感知技术中非常重要的一类,它能够有效解决节点能量受限的问题,保持网络运行的持续性.现有的路由方法并未充分利用节点的能量捕获特性,也没有考虑到链路的成功收包率和节点的传输速率.为进一步提高网络的性能,提出了一种结合链路成功收包率的速率自适应路由算法.通过对节点的剩余能量和链路的成功收包率进行建模,给出了一个节点可作为路由中继节点所需要满足的两个条件;基于优化方程,为传输路径上的每一跳节点自适应配置时延最小化的传输速率;提出路由发现步骤来找出端到端传输时延最小的传输路径.实验结果表明,相比于固定传输速率的路由算法,所提算法所得到的传输路径具有较低的端到端传输时延和较高的吞吐率.  相似文献   

9.
Several approaches have been proposed for designing multihop routing protocols in mobile ad hoc networks (MANET). Many of them adopt a method, called flooding, to discover a routing path. Due to the time-varying nature of the route in MANET, the discovered route needs to be dynamically maintained for optimality in terms of traffic load, hop-distance, and resource usage. It is easy to see that flooding incurs significant overhead and hence is inappropriate for the dynamic route maintenance. In this paper we propose a randomized, dynamic route maintenance scheme for adaptive routing in MANET. The scheme makes use of a nomadic control packet (NCP) which travels through the network based on a random walk, and collects its stopovers as a traversal record. The NCP uses the traversal record to probabilistically provide the nodes with clue for routing path updates. From the clue, the nodes can find the routing path update information that is up-to-date and optimal (less-loaded and shorter), thereby adapting to the dynamic network topology and traffic load conditions. We present an analytical model for measuring the effectiveness of NCP in terms of its frequency of visits and probability of finding the clue from the NCP traversal record. The proposed randomized scheme serves as a routing protocol supporting layer and can be easily applied with minimum modifications to the existing on-demand routing protocols such as AODV and DSR. In our experimental study, we modified the AODV protocol to maintain routing paths using NCPs’ traversal record. Simulation results show that NCPs help the routing protocol to notably reduce average end-to-end packet delay with increased route optimality and better control on traffic congestion.  相似文献   

10.
Chun-Ta Li 《Information Sciences》2011,181(23):5333-5347
More attention should be paid to anonymous routing protocols in secure wireless ad hoc networks. However, as far as we know, only a few papers on secure routing protocols have addressed both issues of anonymity and efficiency. Most recent protocols adopted public key Infrastructure (PKI) solutions to ensure the anonymity and security of route constructing mechanisms. Since PKI solution requires huge and expensive infrastructure with complex computations and the resource constraints of small ad hoc devices; a two-layer authentication protocol with anonymous routing (TAPAR) is proposed in this paper. TAPAR does not adopt public key computations to provide secure and anonymous communications between source and destination nodes over wireless ad hoc networks. Moreover, TAPAR accomplishes mutual authentication, session key agreement, and forward secrecy among communicating nodes; along with integration of non-PKI techniques into the routing protocol allowing the source node to anonymously interact with the destination node through a number of intermediate nodes. Without adopting PKI en/decryptions, our proposed TAPAR can be efficiently implemented on small ad hoc devices while at least reducing the computational overhead of participating nodes in TAPAR by 21.75%. Our protocol is certainly favorable when compared with other related protocols.  相似文献   

11.
In wireless ad hoc networks, end-to-end delivery over network is a critical concern for routing protocols. The capacity of routing protocols is constrained by the intra-flow interference introduced by adjacent nodes on the same path, and inter-flow interference generated by nodes from neighboring paths. In this paper, we develop an on-demand routing protocol M-AODV-R that solves the channel assignment, reuse and routing problem jointly. The proposed channel reuse scheme and channel assignment scheme can enhance channel reuse rate. This cross-layer design approach can significantly improve the performance of multichannel ad hoc networks over existing routing protocols. Simulation results show that the proposed routing M-AODV-R can effectively increase throughput and reduce delay, as compared to AODV protocol.  相似文献   

12.
蓝牙的分散网是一种特殊的自组网.由于蓝牙设备的连接和通信的特性,传统自组网的路由协议不适于蓝牙网络.针对这个问题,提出了一种多径不相交(MPD)的路由算法.仿真结果表明,采用多条路径并行发送数据,提高了数据的投递率,减少了端到端之间的传输延迟,从而有效地减少了网络拥塞;避免了由于路由崩溃,造成系统瘫痪.  相似文献   

13.
提出了一个新的具备安全功能的Ad hoc网多QoS约束的多播路由协议NSQMRAN。该协议采用新型公钥签名算法NTRUSign作为密码机制为路由报文签名,加强了安全性。NSQMRAN为Ad hoc网QoS多播路由协议增加了源认证机制,从而提供了QoS多播路由报文的来源真实性、数据完整性和抗否认等安全服务以抵御恶意节点的攻击。基于NS2的仿真结果表明,在Ad hoc网中,与采用RSA公钥算法的协议相比,采用NTRUSign的NSQMRAN协议网络性能较好,产生较少的端到端延迟。  相似文献   

14.
传统的移动Ad Hoc网络匿名路由协议无法鉴别伪造的路由控制分组,并且公钥运算过多导致路由建立时间延长.提出一种基于邻居认证的安全匿名路由协议以解决上述问题,通过基于临时身份公钥的邻居匿名认证机制鉴定邻居节点合法性并动态协商密钥,路由发现过程中利用邻居协商密钥对路由控制消息进行逐跳的验证与处理.上述机制使得伪造路由分组可被有效鉴别,并且中间节点基于对称密钥运算处理分组降低了路由发现时延.理论分析和仿真结果表明,该协议可对抗基于伪造分组的DoS攻击,并且较传统协议具有更低的路由建立时间.  相似文献   

15.
本文将跨层优化和蚂蚁优化方法结合起来解决自组网中的负载均衡问题,提出了一种基于跨层负载感知和双向逐跳更新信息素的蚂蚁优化路由协议(CLABHPU).协议将整个路径中各节点MAC层的总平均估计时延和节点队列缓存的占用情况结合起来,共同作为路由选择和路由调整的重要依据,进行按需路由发现和维护;通过拥塞节点丢弃蚂蚁分组的方法减少了控制开销,增加了算法的可扩展性,较好地解决了自组网中现有基于蚂蚁算法的路由协议中普遍存在的拥塞问题和路由开销问题.同时,协议在路由发现阶段通过中间节点对信息素表进行双向和逐跳更新,提高了算法的收敛速度和对异常情况的反应速度.通过概率选路提供到目的节点的大量冗余路由,提高了算法的可靠性和顽存性.仿真结果表明,CLABHPU在分组成功递交率、路由开销以及端到端平均时延等方面具有优良性能,能很好地实现网络业务流负载均衡.  相似文献   

16.
张翼  周四望 《计算机工程》2011,37(14):85-87
针对大多数机会网络路由协议在寻找端到端通信链路时不能很好地抓住节点社会性质的问题,提出一种基于历史相遇间隔(HICR) 协议的路由算法。HICR协议利用社会关系的特点,根据节点之间的历史相遇间隔判断它们的亲密程度,转发消息给离目的节点更亲近的节点,使得消息朝更靠近目的节点方向发送。仿真结果表明,该HICR协议在网络资源有限的的情况下,与Epidemic协议和Prophet协议相比,能获得更高的消息交付率。  相似文献   

17.
Bluetooth Location Network (BLN) is a Bluetooth radio network that is composed of some mobile Bluetooth devices and static Bluetooth units, and is established at the system initialization to form a spontaneous network topology. In a BLN, a multicast service is defined as the periodical delivering of messages from a Service Server to a set of mobile devices which are the multicast members predefined by the Service Server. Several multicast protocols have been proposed for the Ad-Hoc networks, but they create an inefficient multicast tree for the BLN due to the existing differences in the radio characteristics between Ad-Hoc and Bluetooth radio networks. The present paper analyzes these differences and proposes a novel multicasting protocol for constructing an efficient multicast tree in a BLN. The proposed protocol constructs a multicast tree with good features which include the shortest path, a higher degree of path sharing, and fewer forwarding nodes. Simulation results reveal that the proposed multicast protocol outperforms the existing multicast protocols in the BLN.  相似文献   

18.
由于节点的移动性、无线链路的带宽有限、可获得的能量有限等原因,对移动Ad hoc网络进行路由提出了具有挑战性的要求。基于位置的路由协议由于不必维护明确的路由,在这种高度动态的网络中具有很好的扩展性。该文通过仿真将一种基于位置的贪婪转发路由:基于改进进程无信标路由(IPPBBLR),与一种基于拓扑的路由:动态源路由(DSR)进行了性能比较。仿真结果表明基于位置的路由比基于拓扑的路由在移动的情况下可以达到更高的发送成功率和更小的端到端延迟,且端到端延迟几乎不受移动速率的影响。  相似文献   

19.
多跳路由协议是无线传感器网络中的关键技术之一,针对传统多跳传输协议在无线传感器网络的实际应用中存在部署过程过于复杂等问题,设计了一种灵活实用的基于Sink节点控制的无线传感器网络多跳传输协议(Sink Controlling Multi-hop Protocol,SCMP)。Sink节点通过发送命令信息实现对传感器节点的控制,并收集各个节点的路由信息从而获得全局路由,然后对传感器节点的数据传输进行进一步控制。在Sun SPOT平台上对SCMP进行了部署实验,结果表明,基于Sink节点控制的多跳传输协议更加方便灵活,在实际的无线传感器网络应用中具有一定的有效性和可行性。  相似文献   

20.
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。  相似文献   

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