移动自组网络中多径路由的匿名安全

多路径为移动自组网络提供的容错、负载均衡与QoS支持较单路径更有效可行,所以在战术无线自组网等类似系统中采用多径路由策略更能满足系统的实际需求.另外,这类系统对安全性的要求除了基本的通信内容机密、完整与可用等特性外,还要求通信者的身份与位置对敌人保密,为通信者及其使命提供保护.鉴于现有的移动自组网络的匿名路由协议都不是实用的多径路由协议,且未能有效防御被动攻击、拜占庭行为以及匿名的不充分性,本文设计了一种新型安全匿名的多径路由协议,其特点是:在移动自组网络中采用单私钥多公钥密码体制、Bloom Filter与轻型洋葱盲化算法,来实现通信者身份匿名、位置隐藏与路由不可追踪;为源节点提供充分的路由信息,基于充分的信息使用强化学习算法来提高系统抵御被动攻击与拜占庭攻击等路由安全攻击的能力,并增强数据传输的可靠性.通过仿真与分析,显示了算法有较好的性能并达到了所定义的匿名安全要求.     

基于部分网络编码的移动自组网实时多播协议研究

传统网络编码可以减少数据包的转发次数,但会造成数据包较大的延时,且容易造成网络的拥塞.本文提出一种基于部分网络编码的实时多播协议——PNCRM.该协议将部分网络编码与mesh的建立结合在一起,有效地减小了端到端的延时,并且改善了网络吞吐量性能.仿真结果表明,与PUMA或基于传统网络编码的实时多播协议相比,PNCRM更好地适应接收节点较多、动态性较大的环境,且在数据包投递率及端到端的延时方面有着显著的优势.     

Multicast Routing in Mobile Ad Hoc Networks

We focus on one critical issue in mobile ad hoc networks that is multicast routing. Advantages and limitations of existing routing protocols are illustrated. Optimal routes, stable links, power conservation, loop freedom, and reduced channel overhead are the main features to be addressed in a more efficient mechanism. In this paper, we propose a new on-demand multicast routing protocol, named Source Routing-based Multicast Protocol (SRMP). Our proposition addresses two important issues in solving routing problems: (i) path availability concept, and (ii) higher battery life paths. SRMP applies a source routing mechanism, and constructs a mesh to connect group members. It provides stable paths based on links' availability according to future prediction of links' states, and higher battery life paths. This protocol succeeded to minimize network load via designing optimal routes that guarantee reliable transmission and active adaptability. A performance comparison study with On-demand Multicast Routing Protocol (ODMRP) and Adaptive Demand-driven Multicast Routing (ADMR) protocol is undertaken. Analysis results show the strength of the SRMP nodes' selection criteria and its efficient energy consumption compared to the other two protocols.     

高动态移动自组网路由协议研究

目前的移动自组网研究主要针对运动速度较慢的地面网络。本文研究由高速节点组成的高动态移动自组网的路由协议,提出了一个结合表驱动路由和地理位置路由的混合路由协议TOPOS,在局部使用表驱动路由加快数据包的转发,而在全局使用地理位置路由以适应快速变化的网络拓扑。在OPNET仿真平台上对TOPOS和已有的AODV及GRP协议的性能比较表明,TOPOS对于节点的运动速度和网络规模具有更好的适应性。     

一种基于网络编码的移动自组网实时多播协议

针对移动自组网中的实时多播场景,提出一种基于网络编码的协议—NCRM.该协议可通过减少网络中数据包的转发次数降低节点能耗,并可改善网络吞吐量性能.为适应实时性要求,在NCRM中引入了严格的时延限制机制.仿真结果显示,与PUMA、MAODV等传统协议相比较,NCRM能更好地适应存在多接收节点、高移动性的环境,且在传输可靠性与节省能耗方面具有显著优势.     

组播路由调度的神经网络方法

本文探讨了在高速包交换计算机网络中，具有端到端时延及时延抖动限制的组播路由问题。首先给出了此类问题的网络模型及其数学描述，然后提出了基于Ｈｏｐｆｉｅｌｄ神经网络的组播路由优化算法。实验表明，本算法能根据组播应用对时延的要求，快速、有效地构造最优组播树，有较强的实时性。     

On-Demand Multicast Routing Protocol in Multihop Wireless Mobile Networks

An ad hoc network is a dynamically reconfigurable wireless network with no fixed infrastructure or central administration. Each host is mobile and must act as a router. Routing and multicasting protocols in ad hoc networks are faced with the challenge of delivering data to destinations through multihop routes in the presence of node movements and topology changes. This paper presents the On-Demand Multicast Routing Protocol (ODMRP) for wireless mobile ad hoc networks. ODMRP is a mesh-based, rather than a conventional tree-based, multicast scheme and uses a forwarding group concept; only a subset of nodes forwards the multicast packets via scoped flooding. It applies on-demand procedures to dynamically build routes and maintain multicast group membership. ODMRP is well suited for ad hoc wireless networks with mobile hosts where bandwidth is limited, topology changes frequently, and power is constrained. We evaluate ODMRP performance with other multicast protocols proposed for ad hoc networks via extensive and detailed simulation.     

An Efficient Multicast Routing Protocol in Wireless Mobile Networks

Providing multicast service to mobile hosts in wireless mobile networking environments is difficult due to frequent changes of mobile host location and group membership. If a conventional multicast routing protocol is used in wireless mobile networks, several problems may be experienced since existing multicast routing protocols assume static hosts when they construct the multicast delivery tree. To overcome the problems, several multicast routing protocols for mobile hosts have been proposed. Although the protocols solve several problems inherent in multicast routing proposals for static hosts, they still have problems such as non-optimal delivery path, datagram duplication, overheads resulting from frequent reconstruction of a multicast tree, etc. In this paper, we summarize these problems of multicast routing protocols and propose an efficient multicast routing protocol based on IEFT mobile IP in wireless mobile networks. The proposed protocol introduces a multicast agent, where a mobile host receives a tunneled multicast datagram from a multicast agent located in a network close to it or directly from the multicast router in the current network. While receiving a tunneled multicast datagram from a remote multicast agent, the local multicast agent may start multicast join process, which makes the multicast delivery route optimal. The proposed protocol reduces data delivery path length and decreases the amount of duplicate copies of multicast datagrams. We examined and compared the performance of the proposed protocol and existing protocols by simulation under various environments and we got an improved performance over the existing proposals.     

自组网环境下利用单向链路的能源节省路由研究

针对自组网中节点电源的容量限制，本文提出了一种利用单向链路的能源节省路由算法。该算法充分利用网络中存在的单向链路，通过让能源较多的节点承担较多的传输任务的方式为数据流选择最佳路由，以延长网络的生存时间。仿真结果证明了该算法的有效性，以及单向链路对于能源节省具有较高的价值。     

A Reliable Multicast Routing Protocol Based on Recovery Points and FEC in Mobile Ad-hoc Networks

Multicasting is an essential service for mobile ad-hoc networks. A major challenge for multicasting in mobile ad-hoc networks (MANETs) is the unstable forwarding path. This work presents a reliable multicasting protocol for mobile ad-hoc networks. A virtual backbone is used as a shared structure for multiple sessions. A lost packet recovery scheme is developed for reliable packet transmission, called the Recovery Point (RP) scheme. The RP scheme maintains the data packets received from the source for recovering lost packets for its downstream RPs. In addition, we combine the Forward Error Correction (FEC) technology with our RP scheme to enhance the reliability of our RP scheme. A mergence scheme for RP is also proposed to avoid excessive control overhead. Our RP and FEC based scheme can be used to improve the reliability and efficiency of the traditional non-acknowledged multicasting approach. Experiments were conducted to evaluate the proposed multicasting scheme. The results demonstrate that our scheme outperforms other schemes in terms of packet delivery ratio and multicast efficiency. Furthermore, the simulation results also demonstrate that our approach is stable in networks with high mobility.

RPSF: A Routing Protocol with Selective Forwarding for Mobile Ad-Hoc Networks

Many existing reactive routing algorithms for mobile ad-hoc networks use a simple broadcasting mechanism for route discovery which can lead to a high redundancy of route-request messages, contention, and collision. Position-based routing algorithms address this problem but require every node to know the position and velocity of every other node at some point in time so that route requests can be propagated towards the destination without flooding the entire network. In a general ad-hoc network, each node maintaining the position information of every other node is expensive or impossible. In this paper, we propose a routing algorithm that addresses these drawbacks. Our algorithm, based on one-hop neighborhood information, allows each node to select a subset of its neighbors to forward route requests. This algorithm greatly reduces the number of route-request packets transmitted in the route-discovery process. We compare the performance of our algorithm with the well known Ad-hoc On-demand Distance Vector (AODV) routing algorithm. On average, our algorithm needs less than 12.6% of the routing-control packets needed by AODV. Simulation results also show that our algorithm has a higher packet-delivery ratio and lower average end-to-end delay than AODV.     

移动Ad Hoc网络组播路由协议的研究综述

移动Ad Hoc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、无基础设施构建快速等特点,从而广泛应用于灾难救助、临时会议、战场指挥等场合。这些应用都涉及到移动Ad Hoc对组播的支持,因此,随着网络应用规模的增长,移动Ad Hoc网络对组播的支持成为一个重要的研究课题。本文对目前的组播路由机制进行了分类和研究,详细描述和比较了这些移动Ad Hoc网络组播路由协议,为组播路由协议和算法进一步的研究提出了新的课题。     

一种节省能量的移动Ad Hoc网络组播选路协议

鉴于现有基于网孔的移动Ad Hoc网络组播选路协议都滑考虑如何有效使用电池能量的问题，本文提出了一种节省能量组播选路协议（E^2MRP),E^2MRP协议的两个主要特征是：（1）在创建和维护中继组（RG）的过程中交替采用分组平均能量消耗最少和最大节点花费最小两种标准，（2）采用基于图的组播结构，本文通过仿真分析大大降低了节点的能量消耗，特别是在节移动性较低，组播成员较少时更是如此。     

EAOMDV-MIMC: A Multipath Routing Protocol for Multi-Interface Multi-Channel Mobile Ad-Hoc Networks

Multipath routing has been proposed to improve performance of mobile ad-hoc networks (MANETs). However, due to: (1) nodes lacking of network interface and (2) route coupling, using multiple paths concurrently in conventional single channel MANETs rarely exhibit performance gain. To improve performance, an ad-hoc routing protocol (and its extension) that utilizes multiple homogeneous network interface is proposed in this paper. Unlike other related multi-channel routing protocols, channels are not assigned. Instead, nodes are allowed to make use of all available channels they are tuned to. In the base protocol, nodes estimate channel conditions by monitoring their network interface queues and distribute data packets to different channels and next-hops according to their conditions. In the extended protocol, estimated channel condition at a node is further propagated to neighboring nodes by piggybacking channel condition information in data packets. With overhearing, other nodes can retrieve this information to make better next-hop selections. Extensive simulation studies show that our protocol outperforms other related multi-channel routing protocols.     

Mobility Aware Quality Enhanced Cluster Based Routing Protocol for Mobile Ad-Hoc Networks Using Hybrid Optimization Algorithm

Wireless Personal Communications - Wireless Sensor Networks (WSN) utilizes more nodes to forward messages and information from source node to destination node and these nodes are battery-powered...     

Reinforcement Learning Based Mobility Adaptive Routing for Vehicular Ad-Hoc Networks

Vehicular ad-hoc networks (VANETs) is drawing more and more attentions in intelligent transportation system to reduce road accidents and assist safe driving. However, due to the high mobility and uneven distribution of vehicles in VANETs, multi-hops communication between the vehicles is still particularly challenging. Considering the distinctive characteristics of VANETs, in this paper, an adaptive routing protocol based on reinforcement learning (ARPRL) is proposed. Through distributed Q-Learning algorithm, ARPRL constantly learns and obtains the fresh network link status proactively with the periodic HELLO packets in the form of Q table update. Therefore, ARPRL’s dynamic adaptability to network changes is improved. Novel Q value update functions which take into account the vehicle mobility related information are designed to reinforce the Q values of wireless links by exchange of HELLO packets between neighbor vehicles. In order to avoid the routing loops caused in Q learning process, the HELLO packet structure is redesigned. In addition, reactive routing probe strategy is applied in the process of learning to speed up the convergence of Q learning. Finally, the feedback from the MAC layer is used to further improve the adaptation of Q learning to the VANETs environment. Through simulation experiment result, we show that ARPRL performs better than existing protocols in the form of average packet delivery ratio, end-to-end delay and number hops of route path while network overhead remains within acceptable ranges.     

Ad Hoc On-Demand Multipath Distance Vector Based Routing in Ad-Hoc Networks

Wireless Personal Communications - Cognitive performance is associated with learning ability and academic success of a student. Since an individual student may lose attention during class, a study...     

基于遗传算法的全光组播路由

该文提出使用遗传算法优化组播业务放置进光网络的顺序,按照此顺序为业务构建组播树并选择波长,以最小化光网络中使用的波长数及组播链路数。比较了3种路由算法的优劣以及波长变换器对资源优化的改善作用。基于NSFNet网络的仿真证明组播能力节点只需占到全网节点数的一半就能达到很好的优化效果。     

Virtual Source Based Multicast Routing in WDM Optical Networks

Wavelength-division multiplexed (WDM) networks using wavelength-routing are considered to be potential candidates for the next generation wide-area backbone networks. Multicasting is the ability to transmit information from a single source node to multiple destination nodes and is becoming an important requirement in high-speed networks. As WDM technology matures and multicast applications become increasingly popular, supporting multicast routing at the WDM layer becomes an important and yet a challenging topic. This paper concerns with the problem of optical multicast routing in WDM networks. A few nodes in the network may have wavelength conversion and/or splitting capabilities. In this paper, a new multicast tree construction algorithm is proposed. This algorithm is based on a concept called virtual source. A virtual source is a node having both the splitting and wavelength conversion capabilities. By exploiting the presence of virtual source nodes, the proposed algorithm achieves improved performance. To further improve the performance, the algorithm assigns priorities to nodes based on their capabilities. The effectiveness of the proposed algorithm is verified through extensive simulation experiments.