Opportunistic Routing Protocols in Wireless Sensor Networks

Wireless Personal Communications - Research on wireless sensor network (WSN) has mainly involved the use of a portable and limited power source, namely batteries, to power the sensors. Without...     

Performance Evaluation of Routing Protocols for Ad Hoc Wireless Networks

A mobile ad hoc network is a collection of autonomous mobile nodes that communicate with each other over wireless links. Such networks are expected to play an increasingly important role in future civilian and military settings, being useful for providing communication support where no fixed infrastructure exists or the deployment of a fixed infrastructure is not economically profitable and movement of communicating parties is possible. However, since there is no stationary infrastructure such as base stations, mobile hosts need to operate as routers in order to maintain the information about the network connectivity. Therefore, a number of routing protocols have been proposed for ad hoc wireless networks. In this paper, we study and compare the performance of the following routing protocols AODV, PAODV (preemptive AODV), CBRP, DSR, and DSDV. A variety of workload and scenarios, as characterized by mobility, load and size of the ad hoc network were simulated. Our results indicate that despite its improvement in reducing route request packets, CBRP has a higher overhead than DSR because of its periodic hello messages while AODV's end-to-end packet delay is the shortest when compared to DSR and CBRP. PAODV has shown little improvements over AODV.     

基于网络编码的无线网络路由协议

基于机会的网络编码方法(COPE)研究网络编码在无线环境中的协议层面上具体实现的问题,但COPE被动地等待编码机会的出现.为了更大限度的提高网络编码的性能,需要将网络编码与无线路由协议相结合来在无线节点上创造出更多的编码机会以减少总的传输次数,以有效的提升网络的吞吐量.当前的编码感知路由算法主要包括基于Markovian路由度量的路由协议、编码感知机会路由协议(CORE)、分布式编码感知路由协议(DCAR)、速率匹配的编码感知多路径路由协议(RCR)、编码感知多路径路由协议(CAMP)等.无线网络内的编码感知路由领域中新型路由度量和跨层设计等问题还需要进一步研究.     

Routing Metrics and Protocols for Wireless Mesh Networks

WMNs are low-cost access networks built on cooperative routing over a backbone composed of stationary wireless routers. WMNs must deal with the highly unstable wireless medium. Therefore, the design of algorithms that consider link quality to choose the best routes are enabling routing metrics and protocols to evolve. In this work, we analyze the state of the art in WMN metrics and propose a taxonomy for WMN routing protocols. Performance measurements for a WMN, deployed using various routing metrics, are presented and corroborate our analysis.     

无线传感器网络路由协议

本文在简要地介绍了无线传感器网络体系结构的基础上,研究了当前主要的几种无线传感器网络路由协议模型,并进行了比较分析.     

多并发流无线网状网中的机会路由算法

现有机会路由选择未考虑数据流的分布,可能使候选节点空闲或过载,导致网络吞吐量提升有限.本文将多并发流的机会路由描述成一个凸优化问题,基于对偶和子梯度方法,提出分布式联合候选节点选择和速率分配的多流机会路由算法(Opportunistic Routing for Multi-Flow,ORMF).该算法迭代进行流速率分配,并在速率分配过程中完成候选节点选择.实验结果表明,与基于期望传输次数和期望任意传输次数指标的机会路由相比,ORMF平均可提高33.4%和27.9%的汇聚吞吐量.     

Ad Hoc网络路由技术

无线自组织网络(Adhoc)是一个复杂的系统,其中路由协议是该领域中的研究热点。通过采用合理的路由技术,可使无线自组网具有更为灵活的组网方式,从而达到提升网络性能、减少网络开销等目的。通过与认知无线电(CR)技术、协同通信(CC)技术以及多输入多输出(MIMO)天线技术等物理层新技术的有效结合,可以大大改善Adhoc路由协议的性能。     

即时无线移动网络及相关路由协议

即时无线网络需要设置固定的路由设备,网络中的每一个移动终端都可以充当路由器,即时无线网络的路由协议包括路由表驱动型路由协议和源节点发起型路由协议。本文分别以无线路由协议和即时指令型距离向量路由协议对上述两类协议进行了详细讨论。     

无线传感器网络路由问题探讨

无线传感器网络（WSN）具有与传统网络显著不同的特点，导致应用于传统网络的路由协议并不适用于无线传感器网络，因此有必要研究新的路由协议为之服务。文中在介绍WSN的特点后，将着重讨论其路由过程并把整个过程分为路由建立和路由更新两个阶段，通过对当前应用较多的路由协议分析，对每个阶段进行阐述；文章最后对WSN路由协议未来的研究策略与发展趋势提出了一些具体研究意见。     

Performance Evaluation of Polling Protocols for Data Transmission on Wireless Communication Networks

The growing interest in mobile computing and communication devices leads to the necessity of wireless broadband network. Data transmission over such networks requires suitable error control schemes to guarantee high data reliability as well as efficient bandwidth utilization.In this paper we propose an accurate yet simple analytical approach to evaluate the performance of wireless networks using gated and exhaustive polling protocols combined with the Stop and Wait (SW) or Go Back N (GBN) ARQ schemes [Bertsekas and Gallager, 2]. Moreover, simulation results concerning the performance of polling protocols combined with the Selective Repeat (SR) ARQ scheme are also shown for comparison purposes.Protocol performance is estimated under very general assumptions, such as: AWGN or fading channels, arbitrary value of the round trip delay and arbitrary distribution of the traffic load (i.e., both symmetric or asymmetric system have been considered).     

Survey of Secure Routing Protocols for Wireless Ad Hoc Networks

The mobile ad hoc network is a type of wireless network characterized by mobile nodes without a centralized administration. Frequent variations of the topology and the nature of the radio links have a negative impact on the stability of the links. Indeed, the link quality deteriorates rapidly and link breaks become frequent. To overcome these problems, new forms of routing protocols are used as the MultiPath routing. In addition, routing protocols require the knowledge of the nodes neighborhood to build and manage routes. The neighbor discovery process is performed by a Hello protocol. The Hello protocol typically involves several parameters such as the packet’s period; node’s transmit power, node’s position and node’s battery level. The purpose of this paper is to change the behavior of ad hoc On demand Multi-path Distance Vector (AOMDV) routing protocol by considering the density of the nodes as well as the interference of the neighboring nodes. This selection of paths goes through two stages. In the first step, we study the impact of the neighbor discovery process to select a set of paths having a minimum number of neighboring nodes to diminish contention problems and interference rate. In the second step, the Interference Ratio (IR) metric is used to select the paths in which the nodes are surrounded by a minimum of interference. We choose for our study two proposed approaches based on AOMDV routing protocol. The first is called AOMDV_neighbor and considers the density parameter as a path metric. The second is called AOMDV_neighbor_IR which considers the interference rate (IR) between each node and its neighborhood as a path metric. We evaluate the proposed routing protocols performance under various NS2 simulation scenarios in a shadowing environment.

     

无线Ad Hoc网络中的QoS路由协议

无线Ad Hoc网络的应用环境以及与Internet的互连都要求其必须提供一定的服务质量(QoS)保证,QoS路由技术是在无线Ad Hoc网络中实现QoS的重要方法。本文对近年来国内外在无线Ad Hoc网络中的QoS路由技术方面取得的研究成果进行了全面的概括总结和分类,对资源预留路由、多径路由和跨层优化路由3类QoS路由协议进行比较分析,并且提出了QoS路由技术亟待解决的问题和今后的发展方向。     

基于能量有效的Ad hoc无线网络路由协议的研究

Ad hoc是一种无固定基础设施的特殊无线网络,此网络中节点一般由电池供能,需要考虑能量有效因素来最大化网络生命周期.对各类基于能量有效的Ad hoc无线网络路由协议进行比较和分析,可以看出路由协议对能量优化有着显著作用.     

无线传感器网络路由协议研究浅析

在无线传感器网络体系结构中,路由技术至关重要。本文描述了无线传感器路由协议所面临的问题与挑战,分析和比较了典型的平面路由协议和层次路由协议。最后总结了理想路由协议应该具有的特点以及路由协议未来的研究策略及发展趋势。     

Cooperative Protocols Design for Wireless Ad-Hoc Networks with Multi-hop Routing

Wireless ad-hoc networks can experience significant performance degradation under fading channels. Spatial diversity has been shown to be an effective way of combating wireless fading with the multiple-input multiple-output (MIMO) technique by transmitting correlated information through multiple antennas. The virtual MIMO technique, which allows multiple wireless stations with single antenna to form a virtual transmission array, is shown to be a viable solution from several recent studies. In this paper, we propose a complete system framework for wireless ad-hoc networks utilizing two different cooperative relaying techniques at the physical layer: the repetition coding and the space-time coding. In the data link layer, two medium access control protocols are proposed to accommodate the corresponding physical layer cooperative diversity schemes. In the network layer, diversity-aware routing protocols are proposed to determine the routing path and the relaying topology. Simulations with both constant bit rate and TCP (transmission control protocol) traffic show significant performance gains of the proposed cooperative relaying schemes.     

A Review on Hierarchical Routing Protocols for Wireless Sensor Networks

The routing protocol for Wireless Sensor Networks (WSNs) is defined as the manner of data dissemination from the network field (source) to the base station (destination). Based on the network topology, there are two types of routing protocols in WSNs, they are namely flat routing protocols and hierarchical routing protocols. Hierarchical routing protocols (HRPs) are more energy efficient and scalable compared to flat routing protocols. This paper discusses how topology management and network application influence the performance of cluster-based and chain-based hierarchical networks. It reviews the basic features of sensor connectivity issues such as power control in topology set-up, sleep/idle pairing and data transmission control that are used in five common HRPs, and it also examines their impact on the protocol performance. A good picture of their respective performances give an indication how network applications, i.e whether reactive or proactive, and topology management i.e. whether centralized or distributed would determine the network performance. Finally, from the ensuring discussion, it is shown that the chain-based HRPs guarantee a longer network lifetime compared to cluster-based HRPs by three to five times.     

多跳无线网路由协议研究进展

移动计算和无线通信的飞速发展为无线网络的应用开辟了美好前景．作为一种没有基础设施的无线网络，多跳无线网在战场、紧急救援等场合具有得天独厚的优势。多跳无线网路由协议的主要作用是监控网络拓扑变化、交换路由信息、产生和维护路由，它是目前的研究热点之一。本介绍了该领域的研究进展，首先叙述多跳无线网的8个特点及其对路由协议的7个要求．然后描述21种路由协议的原理并比较它们的特性，最后阐述了10个研究方向。     

移动传感网中一种基于RSSI的机会主义路由设计

 本文针对移动无线传感网提出一种结合节点移动向量和接收信号强度指示值RSSI(Received Signal Strength Indicator)信息的机会主义路由OR-RSSI,利用Sink节点Beacon报文的RSSI信息建立并更新机会概率值,使用报文广播后所能到达的具有最大机会概率值的最佳节点进行存储转发,完成移动无线传感网信息收集.OR-RSSI是一种良好的后择路由,不以既存路径为基础,不需额外设备支持,具有报文成功传输率高、网络有效吞吐量大以及能耗低等优点.     

QMOR: QoS-Aware Multi-sink Opportunistic Routing for Wireless Multimedia Sensor Networks

The energy efficiency and quality of service (QoS) provisioning of wireless multimedia sensor networks (WMSNs) are two major issues that impact the application of such networks. Recent studies demonstrate that network performance can be greatly improved by involving multiple sinks. However, mainstream WMSN routing protocols are generally designed to account for a single sink. This paper proposes a QoS-aware multi-sink opportunistic routing (QMOR) to efficiently deliver multimedia information under QoS constraints for WMSNs. We begin with an optimal nodes selection problem to reduce redundant multimedia data. Then, we focus on selecting and prioritizing forwarder list to enhance transmission efficiency. Finally, the multi-sink-aware operations are integrated into an optimization opportunistic routing framework, with an objective to minimize energy consumption subject to delay and reliability constraints. Our simulation results demonstrate that the QMOR performs better than typical WMSN QoS routing algorithm, in terms of the video transmission quality and energy utilization efficiency.