以太型局域网吞吐率指标的检测

吞吐率是以太型局域网性能中最重要一项测试指标,利用实际的检测项目,结合最新颁布的国家标准,对这项指标进行检测。利用所测数据判断网络吞吐率是否达到千兆．验证数据包大小变化时引起的吞吐率变化,并将局域网中存在的问题进行分析和解决,最后总结出吞吐率指标测试的关键要素,为以后的相关测试提供参考。     

以太型局域网吞吐率指标的检测

吞吐率是以太型局域网性能中最重要一项测试指标,利用实际的检测项目,结合最新颁布的国家标准,对这项指标进行检测。利用所测数据判断网络吞吐率是否达到千兆,验证数据包大小变化时引起的吞吐率变化,并将局域网中存在的问题进行分析和解决,最后总结出吞吐率指标测试的关键要素,为以后的相关测试提供参考。     

WiMAX Mesh网络中一种集中式QoS调度算法

针对WiMAX Mesh网络集中式下资源的调度和分配,分析了现有调度算法的研究进展与优缺点,结合标准对Mesh模式的QoS定义,提出了一种WiMAX Mesh网络集中式下基于分组的QoS调度算法。通过区分数据流的优先级方式对不同业务数据流进行分组,并计算组内流节点的权值,保证同种业务流间高传输要求和低传输节点的公平性。仿真结果表明,与HRF和LRC算法相比,该算法对于分类业务的时延和网络吞吐量具有明显的优势,实现了区分业务的QoS保障。     

基于收方参与的移动自组网TCP增强的路由协议

移动自组网多跳、动态拓扑的特性,使得路由信息易老化,源节点在路由失败后不能及时启动路由发现,造成TCP有效吞吐率随移动速度增加而下降。在DSR路由协议的基础上,提出一种新的基于接收方参与启动路由发现的新路由协议RP DSR,它通过接收方的ACK确认包启动路由发现,主动为发送方提供最新的路由信息,从而提高了自组网的TCP的性能。仿真结果表明,在节点快速移动环境中,RP DSR协议的TCP性能明显优于DSR协议。     

Multi-slots Wideband Cooperative Spectrum Sensing Based on Weighed Data Fusion in Cognitive Radio

In order to avoid the interference to the primary user(PU), in this paper Cognitive Radio (CR) periodically senses the presence of PU, and during one period, CR can sense all the sub-channels based on weighed data fusion and then use all the idle channels decided by the coordinator. The local sensing time of CR is divided into multi-slots in which CR can sense any sub-channel. Through reasonably allocating the sensing slots and users by mathematic optimization, the proposed algorithm can improve the total throughput of CR. The optimization problem of the proposed scheme which seeks to maximize the throughput subject to the constraint of the detected performance of each sub-channel is proposed in order to choose the optimum local sense time and the number of the cooperative CRs. The simulation results indicate that the proposed scheme can obtain higher throughput than the conventional single-channel sense, and there are the optimum local sense time and the number of cooperative CRs to make the throughput reach maximum.