蚂蚁路由算法中agent分析

就蚂蚁路由算法的agent数量和跳跃步数的行为提出简要分析,并在节点agent数量的期望,agent跳跃步数的期望方面给出结论.提出如何设计k值(对每个请求产生的agent的数目)和agent最大跳跃数以减少对网络流量和主机计算能力的影响.     

蚂蚁路由算法中agent分析

就蚂蚁路由算法的agent数量和跳跃步数的行为提出简要分析,并在节点agent数量的期望,agent跳跃步数的期望方面给出结论.提出如何设计k值(对每个请求产生的agent的数目)和agent最大跳跃数以减少对网络流量和主机计算能力的影响.     

基于历史行为的agent联盟策略

协商是多agent系统中联盟形成的重要手段,很少有对协商初始提议的讨论.提出了一种基于个体历史行为确定协商起点的方法,根据agent在历史任务中的各维能力贡献率,计算其在当前任务中的期望获利因子,并据此给出协商时的初始提议,在此基础上设计了一种联盟形成策略,试验表明了该方法的有效性.     

一种新的最小期望端到端时延路由算法

文章针对最小期望端到端延迟路由算法(the minimum Expected End-to-end Delay,EED)的不足,提出一种新的最小期望端到端时延路由算法(a Novel routing algorithm for End-to-End Delay,NEED)。新算法主要针对EED算法中存在的链路质量评估不合理和MAC传输延迟计算不准确这两个问题提出的,通过仿真验证了NEED路由算法的优越性。     

基于信任机制的协作系统形成与演化机制

通过借鉴人际关系信任模型,利用Bayesian方法对agent的可信度进行评估,提出了一种基于信任机制的多agent协作系统的形成方案。通过agent间基于信任关系的链接更新形成稳定的多agent协作系统,并通过随机图模型分析了提出的协作系统的演化特征。仿真结果证实,提出的协作方案不仅能有效地促进agent间的协作效率,提高共同完成任务的成功率,还能提高整个网络系统的交互性能,使agent聚集在服务能力较强的可信agent周围,保证协作对象选取的可靠性。     

基于矢量映射的多约束服务质量路由计算

针对多维矢量计算多约束服务质量路由出现实际传输路径与源节点期望路径并非一致问题,研究提出矢量映射方式的多约束服务质量路由计算方法。通过数学方法和物理概念相结合的方式,从原理上阐述了新算法矢量映射的合理性,并通过算例和仿真实验方式验证,新算法只需一次性计算就可以获得源节点到各节点保持路径一致的路由。     

多移动代理系统的路由安全管理方案的研究

随着电子商务与网管技术的发展,多移动代理系统得到了广泛应用,同时也使得该系统的路由安全管理更具复杂性与灵活性。该文针对多移动代理系统,提出了一种新的路由安全管理方案。该方案基于保护任务代理的警卫Agent(Proxy agent)的思想,引入了委托信任机制和可信任验证服务器,且对传统的路由表结构进行了改造。方案充分利用了多移动代理协作和交互的优越性,有效提高了路由选择的效率和安全性,同时也保证了最优化。     

基于主动网络层次的多播体系结构

研究了多播路由协议及多播源分发数据报文的机制,提出一种新型的基于主动网络层次的多播体系结构,在自治系统AS中的分枝节点,亦可以根据该策略,构造以分枝节点为根的动态管理方式,从而可以动态地构造层次多播体系结构,在动态层次多播路由的具体实现中引入了agent和主动网络的概念,从而可以动态的加载多播路由,使得网络体系结构灵活与可编程.     

基于组合指标的无线传感器网络安全路由算法

针对无线传感器网络路由安全与可靠性的问题,提出了一种基于组合指标的安全路由算法.评估节点通过观测被评估节点的数据包转发行为,计算直接信任值,然后与第三节点推荐的信任值进行加权求和,得到一个综合信任值.为了提高信任的准确性,避免出现合谋攻击,对第三方推荐的信任值进行了信任相似度检测.通过对期望传输次数和信任值进行加权组合,形成一个用于选择下一跳节点的组合路由指标.最后,对所提出的算法进行了仿真验证.结果表明,所提出的算法能够有效地避免恶意节点的攻击,在传递率和总的传输次数方面明显优于其他算法.     

基于地理-机会的水下无线传感网的混合路由

水下无线传感网络UWSNs被认为是监测海洋最有前景的技术。然而,声信道特性给UWSNs的数据采集提出了挑战。提高UWSNs数据采集效率的有效方式就是融合水下声通信和高动态网络拓扑的特性,设计高性能的路由协议。为此,提出基于地理-机会的水下无线传感网的混合路由,记为GOHR。在GOHR协议中,源节点先计算候选转发节点集,并计算集内每个节点的归一化权重值,再依据归一化权重值对集内节点进行排序,并形成转发节点簇。然后,计算每个簇的期望权重值,最后,选择期望权重值最大的簇内节点作为数据包转发节点。为了避免簇内节点转发数据包时发生碰撞,设置定时延时转发机制。仿真结果表明,提出的GOHR协议提高了数据包传递率,降低了数据包的传输时延。     

一种基于安全移动代理的路由算法设计

移动代理通过遍历网络收集信息,由于网络的开放性,代理及其内部数据的安全受到巨大威胁。提出了一种基于安全移动代理的路由算法的设计思想,使用概率值来构造路由表,通过移动代理在网络节点间地迁移,来发现网络状态,更新节点路由表。同时在网络节点处建立信任表,定期生成TestDataAgent（测试代理）在虚拟空间中运行,并对其属性和关键数据进行检测以保证网络节点的可靠性,实现代理在网络中的安全。还用Grasshopper移动代理开发平台构造了一个简单网络模型,对此算法进行了验证。     

一种面向移动Ad Hoc网络DSR协议的改进泛洪算法

在移动自组织网络中,基于移动节点地理位置辅助信息,提出了一种新的泛洪算法——位置辅助泛洪改进算法（ILFA）,ILFA通过节点位置信息重传广播分组并有效控制网络流量。此外,将ILFA应用于经典MANET源路由（dynamic source routing,DSR）协议中,通过限定请求区域和期望区域等限制路由发现的有效范围,进而通过设置提名广播重传邻居列表限定路由请求分组重传范围,有效减小DSR路由寻路分组的传播次数。仿真结果证明,和传统泛洪方案相比,ILFA能够有效减小DSR路由协议的路由开销并提升MANET吞吐量。     

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.     

QoS routing based on mobile agent for LEO satellite IP networks

Current quality of service (QoS) routing schemes for low earth orbit (LEO) satellites IP networks either neglect the varying population density or fail to guarantee end-to-end delay. As a remedy, QoS routing protocol based on mobile agent (QoSRP-MA) is proposed. QoSRP-MA is a source-based routing protocol. Once connection requests arrive, QoS mobile agents are dispatched from ingress satellite to explore routes, which migrate using satellite routing tables. Upon arriving in egress satellite, QoS mobile agents migrate back towards ingress satellite to reserve bandwidth. To construct satellite routing tables, load balancing routing algorithm based on mobile agent (LBRA-MA) is presented. In LBRP-MA, at regular intervals mobile agents launched on all satellites migrate autonomously to evaluate path cost and update routing tables. Moreover, path cost between source and destination is evaluated considering satellite geographical position as well as inter-satellite link (ISL) cost. Furthermore, ISL congestion index is considered to update routing table. Through simulations on a Courier-like constellation, it shows that QoSRP-MA can achieve guaranteed end-to-end delay bound with higher throughput, lower connection failing ratio and signaling overhead compared to high performance satellite routing (HPSR) scheme.     

GPS/Ant-Like Routing in Ad Hoc Networks

A mobile ad hoc network (MANET) is comprised of mobile hosts that can communicate with each other using wireless links. In this paper we present a novel routing algorithm called GPSAL (GPS/Ant-Like Routing Algorithm) which is based on GPS (Global Positioning System) and mobile software agents modeled on ants for routing in ad hoc networks. We compare our algorithm to the Location-Aided Routing (LAR) [20] algorithm for MANET which is also based on GPS. Simulation results show that our algorithm has less overhead than LAR.     

An incremental deployment algorithm for wireless sensor networks using one or multiple autonomous agents

The paper studies the deployment problem of wireless sensor networks using one or multiple autonomous agents. An online incremental algorithm based on Voronoi partition is proposed to solve the problem, for which each agent deploys sensors one-at-a-time with the objective of using less number of sensors to cover an area and maintain communication connectivity. A probabilistic sensor sensing model is applied for area coverage evaluation. The shape of target area is assumed to be known by the agents, but how the environment affects the communication is unknown a priori. Therefore, the agents are desired to autonomously place every new sensor at an appropriate location based on deployed sensors to ensure connectivity and coverage specifications. Both simulations and experiments using our self-made wireless sensors are conducted to validate the algorithm.     

认知无线网络中基于主用户行为的联合路由和信道分配算法

针对认知无线网络中主用户行为将导致频谱瞬时变化而影响路由稳定性的问题,提出了一种基于主用户行为的路由和信道联合分配算法。该算法通过采用呼叫模型对主用户行为建模,并根据动态源路由协议的路由寻找机制,在目的节点等待多个路由请求分组后选择受主用户行为影响最小的路由,然后沿着所选定路径的反方向传送路由回复分组并完成信道分配。理论分析证明了算法中的链路平均持续时间期望与主用户活动概率成反比且具有与网络节点数成正比的计算复杂度。仿真结果表明,该算法具有比Gymkhana路由方案更高的分组投递率和更低的平均分组时延。     

A novel dynamic survivable routing in WDM optical networks with/without sparse wavelength conversion

In this paper, we study the dynamic survivable routing problem, both in optical networks without wavelength conversion and in optical networks with sparse wavelength conversion, and propose a novel hybrid algorithm for it based on the combination of mobile agents technique and genetic algorithms (GA). By keeping a suitable number of mobile agents in the network to cooperatively explore the network states and continuously report cycles (that are formed by two disjoint-link routes) into the routing tables, our new hybrid algorithm can promptly determine the first population of cycles for a new request based on the routing table of its source node, without the time consuming process associated with current GA-based lightpath protection schemes. We further improve the performance of our algorithm by introducing a more advanced fitness function that is suitable for both the above networks. Extensive simulation studies on the ns-2 network simulator show that our hybrid algorithm achieves a significantly lower blocking probability than the conventional survivable routing algorithms for all the cases we studied.     

基于预期延迟值的扩散转发路由算法

针对现有延迟容忍网络路由算法在消息传递过程中分发不灵活的问题,提出基于节点通话历史记录计算预期通断时长以及消息传递延迟值,并根据结果选择节点、分配副本数进行消息转发的路由算法（MDESF）。在算法不同阶段,根据节点的活跃度选择中继节点,再分配传递消息的副本数目,加快分发,降低延迟。同时为保证消息及时传递,在单副本阶段选择最优节点转发。本算法同时提出内存管理策略,提高消息转发成功率。仿真实验表明,该算法相对其他同类算法在投递率、交付时延和网络拥塞比率方面综合表现更优。     

A cellular coevolutionary algorithm for image segmentation

Clustering is inherently a difficult problem, both with respect to the definition of adequate models as well as to the optimization of the models. We present a model for the cluster problem that does not need knowledge about the number of clusters a priori . This property is among others useful in the image segmentation domain, which we especially address. Further, we propose a cellular coevolutionary algorithm for the optimization of the model. Within this scheme multiple agents are placed in a regular two-dimensional (2-D) grid representing the image, which imposes neighboring relations on them. The agents cooperatively consider pixel migration from one agent to the other in order to improve the homogeneity of the ensemble of the image regions they represent. If the union of the regions of neighboring agents is homogeneous then the agents form alliances. On the other hand, if an agent discovers a deviant subject, it isolates the subject. In the experiments we show the effectiveness of the proposed method and compare it to other segmentation algorithms. The efficiency can easily be improved by exploiting the intrinsic parallelism of the proposed method.