A QoS-aware routing algorithm based on ant-cluster in wireless multimedia sensor networks

QoS-aware routing algorithm is important in wireless multimedia sensor networks. This paper formulates a generalized QoS-aware routing model on the basis of multiple routing metrics and priorities of packets. We first introduce a 2D plain-based routing algorithm IPACR which improves the standard ant colony algorithm by optimizing the initial distribution of artificial pheromone in order to accelerate the algorithm convergence rate. Then a clustering-based routing algorithm ICACR is presented which can be well applied in a large scale network. ICACR is a variation of IPACR because it can be suitable for clustering cases to satisfy the larger scale situations. Both the numerical algorithm performance analysis and simulation of IPACR and ICACR are given. The results show that ICACR outperforms IPACR in terms of both network lifetime and QoS-aware routing metrics in large scale wireless multimedia sensor networks. Moreover, the simulation based on the real video traces shows that by extending the multi-path to ICACR for different priorities of video frames better performance can be achieved.     

无线多媒体传感器网络QoS路由算法研究

由于廉价的CMOS摄像头、麦克风的出现,以及对含有丰富信息的图像,视频和音频信息需求导致了无线多媒体传感器网络-(WMSN)的出现.WMSN具有资源有限、可变的信道容量、数据高度冗余等特点,使得WMSN的QoS路由具有极大的挑战性.提出了一种基于Mesh结构的WMSN,并在该结构体系下,提出了一种基于蚁群算法的QoS路由算法.实验研究表明,蚁群算法具有不依赖全局信息的优点,具有应用于WMSN的前景.实验同时表明,决定蚁群算法收敛速度以及会影响传感器网络性能的一些关键参数较难确定,需要进一步研究.     

一种分布式无线传感器网络跨层移动通信技术研究

针对无线多媒体传感器网络对带宽和实时性等的高要求,建立了一种基于能量优化和跨层协同交互的分布式多路径路由技术,并应用于移动通信领域。该技术采用了遗传算法优化节点传输多媒体数据能耗,建立节点剩余能量预测模型,根据感知能量建立跨层协同工作体系,以较小代价在动态无线网络拓扑中选择最优路径。仿真实验和数学分析表明,该技术能够高效地支持实时移动视频通信,适合于计算能力、存储能力和能量等受限的无线多媒体传感器网络。     

Cross-layer routing metrics for mesh networks: Current status and research directions

Despite efforts to improve the current IEEE 802.11 standard to fully optimize the physical layer, the performance of wireless mesh networks still depends on the routing process for a correct selection of routes. With regard to this question, several cross-layer routing metrics have been developed to improve wireless multi-hop mesh routing. This paper sets out a new taxonomy that can be used to help understand, classify and compare the state-of-the-art situation with regard to cross-layer routing metrics for wireless mesh networks. A simulation study has been carried out to evaluate the capability of the most recent and promising cross-layer routing metrics to support multimedia applications, such as Voice over IP. The evaluation of the routing metrics has been undertaken from three main perspectives: user perception, network performance, and routing stability. The simulation results show that the impact of routing metrics is more noticeable on the network and routing stability evaluation parameters than on the user-perception parameters. Furthermore, the results show that the routing metrics, the level of stability attained, and the application performance are interdependent. Finally, there is a discussion of the direction that future research might take with regard to some open issues in the design of routing metrics for wireless mesh networks.     

无线多媒体传感器网络视频流多路径路由算法

无线多媒体传感器网络中的视频流传输,需要提供多样QoS保障.提出一种基于改进蚁群算法多路径路由算法ACMRA(ant colony based multipath routing algorithm),以寻找具有多种优先级路径的路径集,并对重要性不同的视频数据进行相应路径的选择.通过优化网络链路上人工信息素的初始分布,改进后的蚁群算法具有更快的可行路径发现速度及收敛速度.多路径机制的引入提高了网络数据吞吐量与视频传输性能,同时可均衡网络资源,延长网络生命.实验结果表明,算法ACMRA在网络性能、视频传榆性能与网络生命周期方面,较之其他路由算法具有明显优势.     

一种业务驱动的多媒体传感器网络路由算法

针对多媒体传感器网络承载业务（视频图像业务、音频业务以及数据业务）的差异性和不同业务对QoS的差异性,基于蚁群算法和混沌理论,抽象业务驱动的QoS路由模型,提出了一种业务驱动的路由算法SDR（Service-Driver Routing）。依据各类业务对QoS的差异性选择相应路由策略,达到充分利用网络资源、提高网络承载业务性能的目标。采用NS2对该算法进行实验仿真,实验结果表明,与其他路由算法相比,该算法可提供区分业务的QoS保障。     

无线传感器网络路由算法仿真模型的研究

随着计算机技术、网络技术、无线通信技术的发展,当前在通信领域形成了一种无线传感器网络,无线传感器网络有诸多优势和功能,应用范围非常广,因为自身的特点,使得无线传感器网络的发展、技术等面临着新的挑战。无线传感器网络从组成到功能均和传统的无线通信网络不同,无线传感器网络的路由算法在不断地创新和突破。在无线传感器网络路由算法的设计中,需要将所有的资源高效利用放在首位,建立路由计算仿真模型。针对无线传感器网络路由算法的仿真模型进行了研究分析。     

多QoS约束的层次多播路由算法框架

为了解决网络路由的扩展性问题。大型网络通常被划分成若干个不同的域。拓扑聚集是对这些域的拓扑状态信息进行汇总的过程。在拓扑聚集的基础上，QoS层次多播路由算法用来构造满足QoS要求的域闻多播树。现有的QoS层次多播路由算法在其拓扑聚集和路径计算的过程中都只考虑了存在两个QoS特征值的情况。本文提出了一种具有多QoS约束的层次多播路由算法框架HMRMQ（Hierarchical Multicast Routing with Multiple QoS constraints），此算法框架不仅为基于多QoS特征值的拓扑状态聚集和状态信息表示提供了新的方法，而且提出了一种适应于多QoS约束的层次多播路由新算法。我们提出的状态信息表示法和拓扑聚集算法都具有很好的扩展性，分布式的路由算法也便于某些安全性策略的实施。理论分析和实验结果不仅证明了HMRMQ的正确性和有效性，同时也表明了HMRMQ在网络路由的扩展性、路由成功率、网络代价以及报文负载等方面都具有良好的性能。     

An agent-assisted QoS-based routing algorithm for wireless sensor networks

Existing routing algorithms are not effective in supporting the dynamic characteristics of wireless sensor networks (WSNs) and cannot ensure sufficient quality of service in WSN applications. This paper proposes a novel agent-assisted QoS-based routing algorithm for wireless sensor networks. In the proposed algorithm, the synthetic QoS of WSNs is chosen as the adaptive value of a Particle Swarm Optimization algorithm to improve the overall performance of network. Intelligent software agents are used to monitor changes in network topology, network communication flow, and each node's routing state. These agents can then participate in network routing and network maintenance. Experiment results show that the proposed algorithm can ensure better quality of service in wireless sensor networks compared with traditional algorithms.     

OMNeT++平台上无线传感器网络仿真系统的研究*

仿真系统对于无线传感器网络尤其是大规模无线传感器网络的性能评价是必不可少的。通过仿真,人们能够在一个可控的环境里研究无线传感器网络,观察由不可预测的干扰和噪声引起的节点间的相互作用,减少投放后的网络维护工作。OMNeT++是一款开源的、基于组件的、模块化的开放网络仿真平台。在OMNeT++平台提供的网络仿真基础类库和开发环境的基础上,紧密结合无线传感器网络自身特点,从仿真模型、实现机制和应用场景等方面设计了无线传感器网络仿真系统,并在Linux操作系统上编程实现。通过实验验证,该仿真模型可以正确仿真MAC     

Ant-based routing for wireless multimedia sensor networks using multiple QoS metrics

In wireless sensor networks, most routing protocols consider energy savings as the main objective and assume data traffic with unconstrained delivery requirements to be a given. However, the introduction of video and imaging sensors unveils additional challenges. The transmission of video and imaging data requires both energy efficiency and QoS assurance (end-to-end delay and packet loss requirements), in order to ensure the efficient use of sensor resources as well as the integrity of the information collected. This paper presents a QoS routing model for Wireless Multimedia Sensor Networks (WMSN). Moreover, based on the traditional ant-based algorithm, an ant-based multi-QoS routing metric (AntSensNet) is proposed. The AntSensNet protocol builds a hierarchical structure on the network before choosing suitable paths to meet various QoS requirements from different kinds of traffic, thus maximizing network utilization, while improving its performance. In addition, AntSensNet is able to use a efficient multi-path video packet scheduling in order to get minimum video distortion transmission. Finally, extensive simulations are conducted to assess the effectiveness of this novel solution and a detailed discussion regarding the effects of different system parameters is provided. Compared to typical routing algorithms in sensor networks and the traditional ant-based algorithm, this new algorithm has better convergence and provides significantly better QoS for multiple types of services in wireless multimedia sensor networks.     

An efficient joint channel assignment and QoS routing protocol for IEEE 802.11 multi-radio multi-channel wireless mesh networks

With the emerging of video, voice over IP (VoIP) and other real-time multimedia services, more and more people pay attention to quality of service (QoS) issues in terms of the bandwidth, delay and jitter, etc. As one effective way of broadband wireless access, it has become imperative for wireless mesh networks (WMNs) to provide QoS guarantee. Existing works mostly modify QoS architecture dedicated for ad hoc or sensor networks, and focus on single radio and single channel case. Meanwhile, they study the QoS routing or MAC protocol from view of isolated layer. In this paper, we propose a novel cross-layer QoS-aware routing protocol on OLSR (CLQ-OLSR) to support real-time multimedia communication by efficiently exploiting multi-radio and multi-channel method. By constructing multi-layer virtual logical mapping over physical topology, we implement two sets of routing mechanisms, physical modified OLSR protocol (M-OLSR) and logical routing, to accommodate network traffic. The proposed CLQ-OLSR is based on a distributed bandwidth estimation scheme, implemented at each node for estimating the available bandwidth on each associated channel. By piggybacking the bandwidth information in HELLO and topology control (TC) messages, each node disseminates information of topology and available bandwidth to other nodes in the whole network in an efficient way. From topology and bandwidth information, the optimized path can be identified. Finally, we conduct extensive simulation to verify the performance of CLQ-OLSR in different scenarios on QualNet platform. The results demonstrate that our proposed CLQ-OLSR outperforms single radio OLSR, multi-radio OLSR and OLSR with differentiated services (DiffServ) in terms of network aggregate throughput, end-to-end packet delivery ratio, delay and delay jitter with reasonable message overheads and hardware costs. In particular, the network aggregate throughput for CLQ-OLSR can almost be improved by 300% compared with the single radio case.     

多要素无线传感监控网络中的多路径路由

在多要素无线监控网络中,涉及图形、图像、视频等要素的采集和传输,而传统的传感网络路由在这种高负载的网络中表现出性能上的不足。为了高效地传输监控信息,针对这一网络中多路径路由进行优化设计,提出利用梯度导向的启发式信息来指导路由路径的建立,从而提高路径建立的能效。同时,针对监控节点分布的稀疏和稠密两种情况,提出基于梯度信息的贪婪式转发路径创建算法GBGF和基于梯度信息的受限广播路径创建算法GBRB。模拟结果显示,基于梯度思想的引入对多径路由的能效有极大的提高。     

基于最小生成超树的无线传感器网络路由算法研究

设计能量有效的路由协议以延长网络生存周期,提供健壮可靠的网络服务成为资源有限无线传感器网络研究的核心问题.研究并采用超图理论,将大规模,高连通度的无线传感器网络拓扑抽象为超图模型,从而有效减少网络控制消息.并基于超图模型提出同步无线传感器网络最小生成超树路由算法,以建立数据汇聚的最小能耗树.随后理论证明MSHT-SN算法的正确性和有效性.通过仿真,基于超图模型的MSHT-SN算法较优于基于最短路树策略路由算法,其能够有效的提高数据传输成功率,并节省网络总能耗,延长网络生存周期.     

能量均衡的无线传感器网络节点路由算法

为了提高无线传感器网络的生存时间,提出一种能量均衡的无线传感器网络节点路由算法。首先利用能量阈值和节点剩余能量将节点归类为2个区域,使得不同区域的节点当选为本轮簇头节点的概率不同,在数据稳定传输阶段,簇头与基站之间采用单跳与多跳相结合的通信方式,最后采用仿真实验测试算法的性能。结果表明,本算法有效提高了网络的能量利用率,能够实现节点之间的能耗均衡,使无线传感器的网络生存时间得到延长。     

事件驱动的无线多媒体传感器网络QoS通信协议

提出一种事件驱动的无线多媒体传感网QoS感知通信(EDQC)协议。首先,当监测到事件发生时,在满足事件监测质量的基础上,启动最少的视频节点进行数据采集,以减少冗余数据的产生。其次,在数据传输阶段,计算由前进距离、队列长度和剩余能量构成的复合权值,并选择权值最大的下一跳节点进行数据转发,从而避开拥塞区域、延长网络生存周期。仿真结果表明,EDQC协议能够较好的适应视频监测需求,同时减少通信拥塞、均衡节点能耗。     

基于路径质量的无线传感网路由协议

基于跳数的无线传感器网络路由协议因实现简单、延迟少和易维护等优点,一直以来受到广泛关注。在分析现有基于跳数的路由协议的基础上,对最小跳数路由算法的选路标准进行了改进,提出了一种基于路径质量的无线传感网路由协议,采用跳数、综合链路质量和节点能量作为路径质量的度量指标。使用OMNET++网络仿真软件进行了仿真实验,实验结果表明：改进后的路由协议有效地提高了网络分组的投递率,降低了网络的能耗。     

基于隶属云蚁群算法的长链型无线传感器网络路由优化

针对用于监测系统的长链树状无线传感器网络数据传输的实时性和高可靠性等要求,并考虑到近汇聚节点处易形成"漏斗"等问题,本文提出用基于云模型的多蚁群算法对无线传感器网络路由进行跨层优化的设计思想。算法通过种群间信息素的相互作用并行地完成路径的搜索并及时对信息素进行更新,在搜索的过程中把节点的时延、跳数、负载及分组成功率作为路径的启发值,利用多规则云发生器对更新策略中的信息素残留系数和信息素强度进行自适应调整。仿真结果表明,该路由算法能够保证无线传感器网络具有很强的实时性、可靠性及鲁棒性,实现了网络的负载平衡及拥塞控制机制。     

无线传感网络中拥塞控制与路由的跨层设计:分布式牛顿法

无线传感网络应用广泛, 其性能与路由选择和拥塞控制密切相关. 致力于拥塞控制与多径路由的跨层优化, 以实现在链路容量受限和节点能量受限情况下的无线传感网络效用最大化. 针对对偶次梯度算法具有收敛速度慢与信息交互量大等缺陷, 设计了具有二阶收敛性能的分布式牛顿算法来实现网络效用最大化. 通过矩阵分裂技术, 实现了只需单跳信息交互的牛顿对偶方向的分布式求解方法. 仿真结果表明, 分布式牛顿算法的收敛性能显著优于对偶次梯度算法.     

基于遗传算法的无线传感器网络路由协议研究*

针对无线传感器网络能量受限、建立高效路由困难等特点,将遗传算法应用于无线传感器网络路由协议中,提出了一种快速构建无线传感器网络最优路径方法。采用可变长度染色体编码,采取选择、交叉和变异操作,充分利用基站的信息资源和强大计算功能,逼近无线传感器网络最优路径。仿真结果表明,基于遗传算法的无线传感器网络路由协议可以有效延长无线传感器网络的生命周期,改善网络性能。