基于MANET的QoS多播路由协议研究

在自组织网络上运行多媒体应用,正在成为随遇计算和随遇通信环境中的一个完整部分,同时提出了对QoS和多播的需求,如何设计有效的QoS多播路由协议已经成为当前研究的热点问题。本文介绍了自组网QoS多播路由协议研究方面的一些最新进展,并对该研究所提出的路由算法进行了比较和分析,有助于进一步改进和完善自组网的QoS多播路由技术。     

Context-aware RAON middleware for opportunistic network

Application development and deployment on Mobile Ad Hoc Networks (MANET) is a major challenge in the widespread use of MANET. The increasing D2D communication in 5G networks has renewed interest in an effective middleware design for MANET where application developers face various challenges such as unstable connectivity, high error rate, mobility induced disruption and disconnection, and limited battery power. We find that unstructured overlay network provides a good abstraction to facilitate application development and deployment on MANET. In this paper, we present the design of a middleware that builds a Resource-Aware Overlay Network (RAON), which is an unstructured overlay network of nodes engaged in the application that employs a query–reply mechanism for resource discovery. RAON is enhanced with features such as proactive neighbor replacement, congestion-aware data download and cooperative caching. Simulation results show that these features are effective in reducing query delay, improving data availability, and balancing node power consumption with protocol performance. We also present the middleware software design that offers the API based on node and path abstractions to applications. The middleware implements a generic context framework for acquiring device and user context. We discuss the implementation of application-level multicast and credit-based file-sharing applications using the middleware API. The middleware is implemented in Java J2ME on Android, which is tested in an ad hoc network of Nexus 7 devices running OLSR.     

两种Ad hoc网络组播路由协议的性能比较和分析

目前研究人员已提出多种Adhoc网络组播路由协议,根据MANET制定的路由协议性能评价标准,还没有一种组播路由协议能满足所有的性能要求,因此对协议在各种应用环境下的性能进行测试和比较,有助于人们选择和设计组播路由协议。该文首先介绍了两种组播路由协议—ODMRP和DBRMP的基本思想,接着提出这两种协议的控制开销计算方法,并对它们的性能进行了定性比较,最后使用了NS-2仿真平台对两种组播路由协议在各种应用环境下的性能进行了仿真,并根据仿真结果详细比较和分析了两种协议在各种应用环境下的性能特点。     

主动层次多目通信路由模型

许多应用需要IP多目通信.在Internet大规模应用IP Multicast时,有效的路由是关键.这样的多目路由协议必须是有效的、可伸缩的和增量可配置的.但是传统的Internet路由对性能是不敏感的,不能平衡负载和处理拥塞.现有的大多数多目通信路由协议不仅负责数据转发,还负责路由树的构造,这给路由器带来了极大的复杂性,而且协议的配置是手动的、费时费钱的工作.该文提出一个主动层次式Multicast路由的体系结构,采用主动网络技术将多目通信路由协议的数据转发和控制机制分开,根据链路的状态信息用主动报文控     

基于流量预测的移动Ad hoc网联合组播路由协议

组播是移动Ad hoc网络一项重要应用技术,而路由协议的研究一直是组播技术研究的重点。相关研究已经表明在MANET中传统的分层方法对提高网络性能并不有效。该文在流量预测的基础上,联合PHY层、MAC层、LL层、网络层的相关基本信息提出了一种联合路由标准,并给出了基于ODMRP和跨层设计方法的一种联合组播路由协议方案。该方案既保证网络层次的独立性,又能方便各网络分层间的信息交换,避免了跨层设计所带来的复杂性。模拟结果显示联合路由协议的综合性能比ODMRP要好。     

三种Ad Hoc网络组播协议的性能分析与比较

近年来,Ad hoc网络的组播路由协议研究受到广泛关注,但已经提出的各种组播协议中还没有一种在MANET定义的各种性能指标方面都处于领先,因此对不同协议的分析和比较能帮助人们在不同的应用环境下选择和设计更适合的组播协议。本文首先分别介绍了3种典型的组播路由协议：ODMRP、ADMR、DRMR,然后对其控制开销进行了计算分析,最后利用NS2仿真软件对3种协议进行仿真,分析与比较了它们在各种网络环境下的性能。     

The performance impact of traffic patterns on routing protocols in mobile ad hoc networks

As mobile ad hoc network (MANET) systems research has matured and several testbeds have been built to study MANETs, research has focused on developing new MANET applications such as collaborative games, collaborative computing, messaging systems, distributed security schemes, MANET middleware, peer-to-peer file sharing systems, voting systems, resource management and discovery, vehicular computing and collaborative education systems. The growing set of diverse applications developed for MANETs pose far more complex traffic patterns than the simple one-to-one traffic pattern, and hence the one-to-one traffic pattern widely used in previous protocol studies has become inadequate in reflecting the relative performance of these protocols when deployed to support these emerging applications.As a first step towards effectively supporting newly developed and future diverse MANET applications, this paper studies the performance impact of diverse traffic patterns on routing protocols in MANETs. Specifically, we propose a new communication model that extends the previous communication model to include a more general traffic pattern that varies the number of connections per source node. We study the performance impact of traffic patterns on various routing protocols via detailed simulations of an ad hoc network of 112 mobile nodes. Our simulation results show that many of the conclusions drawn in previous protocol comparison studies no longer hold under the new traffic patterns. These results motivate the need for performance evaluation of ad hoc networks to not only include rich and diverse mobility models as has been done in the past but also include diverse traffic patterns that stress a wide set of protocol design issues.     

Standardisation advancements in the area of routing for mobile ad-hoc networks

Mobile Ad hoc Networks (MANETs) are self-organized and fully distributed networks that rely on the collaboration of participating devices to route data from source to destination. The MANET paradigm is expected to enable ubiquitous mobile communication and thus the proliferation of pervasive applications. The MANET Working Group (WG) of the Internet Engineering Task Force (IETF) is responsible for standardizing an appropriate Internet Protocol (IP) based routing protocol functionality for both static (mesh) and dynamic (mobile) wireless ad hoc network topologies. In this paper, we provide a background on the possibility to use MANETs for enabling future pervasive internet and innovative ubiquitous services. We also describe the work achieved by the MANET WG thus far on the area of secure unicast and multicast routing for MANETs. We also examine non-IETF work on this area, chiefly based on adaptive and hybrid routing. The paper then presents comparative performance evaluations of discussed routing protocols. It is mainly observed that there is a need for adaptive hybrid routing approaches in order to support future innovative and pervasive applications. Consequently, we present our conclusions.     

Using particle swam optimization for QoS in ad-hoc multicast

A mobile ad hoc network (MANET) is a collection of self-organized mobile nodes that are capable of communicating with each other without the aid of any established infrastructure or centralized administration. Multicasting plays a very important role in the application of ad hoc networks. As the number of participants increases, scalability of the multicast protocol becomes an important issue. When considering the increasing demand of Quality-of-Service (QoS) requirements in many applications, the existing multicast routing protocols used for ad-hoc network should be adapted appropriately to effectively meet the stringent QoS requirements of specific multimedia traffic. We thus propose a multicast routing protocol which tries its best to meet the variation of behavior of network topology and satisfy QoS requirements of specific multimedia traffic using particle swam optimization (PSO) in the volatile environments of a MANET. Meanwhile, a priority scheduler with PSO is also proposed to make scheduling decisions so that the packet loss rate can be further reduced. The results of a series of simulations exhibit the practicability and feasibility of our protocol.     

基于贪婪覆盖集的MANET自适应组播路由算法研究

MANET所具有的分布式、多跳、自组织、动态拓扑、时变信道、资源受限等特点,使得传统的有线网和有中心无线网络的路由算法和协议无法在MANET中直接应用,为此需要根据MANET的特点设计专门的组播路由算法和协议.结合基于Mesh和基于树形转发结构两类MANET组播路由的优点,提出一种基于贪婪覆盖集(Greedy Set Cover)的MANET组播路由算法ADMMR(Adaptive Distributed MANET Multicast Route based on Greedy Set Cover),节点可以动态地、分布式计算各自的转发列表,根据转发列表进行组播数据的转发,节省有限的带宽,减少信道冲突,降低网络负载,提高算法的总体性能.最后运用OPNET验证了该算法的有效性.     

Research on multicast routing protocols for mobile ad-hoc networks

A mobile ad-hoc network (MANET) is composed of mobile nodes without any infrastructure. Mobile nodes self-organize to form a network over radio links. The goal of MANETs is to extend mobility into the realm of autonomous, mobile and wireless domains, where a set of nodes form the network routing infrastructure in an ad-hoc fashion. The majority of applications of MANETs are in areas where rapid deployment and dynamic reconfiguration are necessary and wired network is not available. These include military battlefields, emergency search, rescue sites, classrooms and conventions, where participants share information dynamically using their mobile devices. These applications lend themselves well to multicast operations. In addition, within a wireless medium, it is crucial to reduce the transmission overhead and power consumption. Multicasting can improve the efficiency of the wireless link when sending multiple copies of messages by exploiting the inherent broadcast property of wireless transmission. Hence, reliable multicast routing plays a significant role in MANETs. However, to offer effective and reliable multicast routing is difficult and challenging. In recent years, various multicast routing protocols have been proposed for MANETs. These protocols have distinguishing features and employ different recovery mechanisms. To provide a comprehensive understanding of these multicast routing protocols and better organize existing ideas and work to facilitate multicast routing design for MANETs, we present the taxonomy of the multicast routing protocols, their properties and design features. This paper aims to aid those MANETs researchers and application developers in selecting appropriate multicast routing protocols for their work.     

Link stability based multicast routing scheme in MANET

The group-oriented services are one of the primary application classes that are addressed by Mobile Ad hoc Networks (MANETs) in recent years. To support such services, multicast routing is used. Thus, there is a need to design stable and reliable multicast routing protocols for MANETs to ensure better packet delivery ratio, lower delays and reduced overheads. In this paper, we propose a mesh based multicast routing scheme that finds stable multicast path from source to receivers. The multicast mesh is constructed by using route request and route reply packets with the help of multicast routing information cache and link stability database maintained at every node. The stable paths are found based on selection of stable forwarding nodes that have high stability of link connectivity. The link stability is computed by using the parameters such as received power, distance between neighboring nodes and the link quality that is assessed using bit errors in a packet. The proposed scheme is simulated over a large number of MANET nodes with wide range of mobility and the performance is evaluated. Performance of the proposed scheme is compared with two well known mesh-based multicast routing protocols, i.e., on-demand multicast routing protocol (ODMRP) and enhanced on-demand multicast routing protocol (EODMRP). It is observed that the proposed scheme produces better packet delivery ratio, reduced packet delay and reduced overheads (such as control, memory, computation, and message overheads).     

QMRPRNS: Design of QoS multicast routing protocol using reliable node selection scheme for MANETs

A mobile Ad-Hoc networks (MANETs) is a continuously self-configuring, infrastructure-less network of wireless mobile devices. In which multicast is one of the efficient way of communication. Currently, several research have been conducted to design multicast routing protocols for wireless mobile ad-hoc networks (MANETs). Multicasting is a technique that allow to send the same message to a group of destinations simultaneously. However, it faces several challenges against its implementation in ad-hoc network due to its dynamic nature, lack of bandwidth, short battery lifetime of the mobile devices. The multicast routing protocol MAODV have several constraints as mentioned above. Hence to address these constraints a reliable neighbour nodes selection scheme has been integrated over MAODV. This paper attempt a Quality of Service (QoS) based multicast routing protocol using reliable neighbour nodes selection scheme (QMRPRNS) for same. The simulation has been conducted to compare the performance of the proposed scheme against some existing multicast routing protocols which shows significant improvement over EMAODV and MAODV.     

MANET中基于遗传算法的QoS多播路由协议

随着多媒体业务的普及,如何为MANET多播路由提供QoS保障成为研究热点。提出了一种带宽和时延受限的QoS多播路由协议,它利用遗传算法搜索满足QoS要求的最优多播树。仿真结果表明该协议收敛速度快,寻径成功率高,它为移动网络中具有QoS保障的多播通信提供了一种有效途径。     

基于MANET的QoS路由协议研究

移动自组网(MANET)是建立军事和民用快速通信系统的理想技术。如何在MANET中提供不同的服务质量(QoS)是其面临的一个重要问题,而QoS路由技术则是其中的核心技术和热点问题。文章对不同研究者提出的几种QoS路由算法进行了分析和研究,并从单向链路的支持、多播功能以及QoS参数选择几个方面进行了比较和分析,有助于进一步改进和完善MANET的QoS路由技术。     

移动自组网QoS组播路由协议的研究

针对已有的移动自组网中QoS路由协议进行了分析比较,提出了一种基于逻辑超立方体的虚拟动态骨干网模型以支持QoS组播通信。该模型具有高可用性和负载均衡的特性，而这两种特性是在移动自组网中提供QoS保证的重要前提。基于该模型又设计了一种新颖的基于逻辑位置信息的QoS组播路由算法：自路由，模拟结果显示该算法性能良好，具有延迟小、抖动小、容错性强的特点。     

移动Ad Hoc网络多播路由协议的研究进展

移动AdHoc网络是一个自组织、移动节点通过无线链路组成的动态拓扑变化的网络.由于网络规模小、无基础设施、构建迅速等特点,从而广泛用于紧急事件、军事和民用领域以及多媒体应用等.随着网络应用规模的增长,在移动AdHoc网络中支持多播路由成为网络领域中一类重要的研究课题.该文综述了移动AdHoc网络多播路由方面的一些最新工作,论述了设计移动AdHoc网络多播路由协议的特性、问题和技术,详细描述和比较了目前典型的移动AdHoc网络多播路由协议,为进一步的应用和研究提出了新的课题.     

An efficient fault-tolerant multicast routing protocol withcore-based tree techniques

In this paper, we design and analyze an efficient fault-tolerant multicast routing protocol. Reliable multicast communication is critical for the success of many Internet applications. Multicast routing protocols with core-based tree techniques (CBT) have been widely used because of their scalability and simplicity. We enhance the CBT protocol with fault tolerance capability and improve its efficiency and effectiveness. With our strategy, when a faulty component is detected, some pre-defined backup path(s) is (are) used to bypass the faulty component and enable the multicast communication to continue. Our protocol only requires that routers near the faulty component be reconfigured, thus reducing the runtime overhead without compromising much of the performance. Our approach is in contrast to other approaches that often require relatively large tree reformation when faults occur. These global methods are usually costly and complicated in their attempt to achieve theoretically optimal performance. Our performance evaluation shows that our new protocol performs nearly as well as the best possible global method while utilizing much less runtime overhead and implementation cost     

一种基于分群的移动自组网多播路由协议

为提高多播协议的可扩展性,提出一个基于分群的高效多播路由协议(ECMRP)。采用改进的基于权重的分群算法对移动自组网中的移动节点进行分层管理,并应用软状态方法在群首间建立多播树,减小当网络拓扑结构动态变化时重构、维护多播树结构的控制开销。仿真实验结果表明,该算法在路由开销和分组投递率上均优于多播按需距离矢量和按需多播路由协议,更适合于高动态、大规模的自组网。