GPON基于流量检测的动态带宽分配算法研究及改进

针对GPON系统基于流量检测动态带宽分配算法,对通过检测已分配带宽的利用率来动态分配带宽的算法进行了研究,并根据此算法在实际使用过程中出的问题,提出对此算法的改进方案,给出算法改变前后的实际运行结果的比较.     

利用SDGP算法进行实时动态带宽分配的研究及仿真

提出一种在网络通信带宽分配领域,结合自动控制理论,利用基于优先级的串行主导因子法对链路带宽进行动态分配的方案。该算法通过引入主导因子和容忍因子,可以实现在具有流量工程基础的网络中对共享带宽进行实时动态分配。     

APON技术及其实现方案

介绍了基于ATM的无源光网络(APON)的优点,并对实现APON所存在的测距、突发同步、突发发射和接收、上行带宽动态分配以及加密等关键技术进行了分析,提出了APON的一种实现方案——ADSL+APON的综合接入系统。     

基于带宽需求预测的VBR业务速率分配

本文在对VBR业务带宽需求预测的基础上 ,提出了一种综合考虑信元丢失率、信道利用率、缓冲延时和缓冲器容量需求等方面的VBR业务频带动态分配的方法。对如何确定有关控制参数等问题 ,进行了研究 ,并就运用最佳线性预测和递归最小二乘法(RLS)等估计理论 ,对VBR业务流量速率的预测和控制 ,系统的性能作了分析和模拟     

基于Mininet的SDN带宽测试研究

基于Mininet,分别通过控制器和硬件性能的不同测试SDN的带宽性能.结果表明,控制器的性能差异决定SDN的带宽性能,硬件配置的高低也影响到网络带宽的大小.因此实施者在实际部署SDN时,应该考虑这些因素,选择最合适的方案.     

LonWorks测试系统的设计

采用模块化结构设计了电力线载波网络性能测试系统,对网络的延时、带宽和误码率进行测试,使用电力线通信分析仪PLCA-22对此电力线载波网络的延时、带宽和误码率进行测试,以验证此性能测试系统设计的正确性.     

一种APON上行带宽分配方案

文中介绍了APOW（ATM无源光网络）,在此基础上提出了APON上行带宽动态分配的一种方案--“最小分配”方案：即光线路终端（OLT）在分配上行带宽时,首先满足各光网络单元（ONU）的基本带宽需求,以保证电话等实时业务的传输;同时又以特定的算法使ONU中的上行发送缓冲队列最短。最后,使用仿真手段对本方案与“平均分配”方案进行了性能比较。“最小分配”方案的平均信元接入时延、ONU上发缓冲区尺寸、上行带宽使用效率和信元丢失率等性能指标均优于“平均分配”方案。     

基于还宽需求预测的VBR业务速率分配

本文在对ＶＢＲ业务带宽需求预测的基础上，提出了一种综合考虑信元丢失率、信道利用率、缓冲延时和缓冲器空量需求等方面的ＶＢＲ业务频带动态分配的方法。对如何确定有关控制参数等问题，进行了研究，并就运用最佳线性预测和递归最小地乘法（ＲＩＳ）等估计理论，对ＶＢＲ业务流量速率的预测和控制，系统的性能作了分析和模拟。     

面向软件定义网络（SDN）的新型交换技术实验研究

本文主要内容是基于Mininet分别搭配POX和Floodlight的Linux实验测试平台,采用Python编程控制网络结构与控制器,并模拟多数据中心网络进行实验,通过Python编写网络拓扑结构,测试主机终端的带宽性能,最终使用Python脚本实现自动化测试节点、链路以及带宽等参数;使用FloodLight控制器对主机间的流表进行分析,深入理解OpenFlow协议。优化扩展了传统胖树结构的数据中心,测试数据结果相比传统结构测试更好;抓包分析建立OpenFlow流表的过程来更好的理解控制转发分离的思想。     

一种基于固定长度的EPON动态带宽分配方案

文中介绍了以太无源光网络(EPON),在此基础上提出了EPON的上下行帧结构,以及基于固定长度的一种EPON动态带宽分配方案。该方案以APON为借鉴,将EPON中以太网帧长度固定下来,采用对业务分时延优先级的动态分配算法。并对此方案的性能进行了分析。     

Bandwidth Reallocation for Bandwidth Asymmetry Wireless Networks Based on Distributed Multiservice Admission Control

This paper addresses when and how to adjust bandwidth allocation on uplink and downlink in a multi-service mobile wireless network under dynamic traffic load conditions. Our design objective is to improve system bandwidth utilization while satisfying call level QoS requirements of various call classes. We first develop a new threshold-based multi-service admission control scheme (DMS-AC) as the study base for bandwidth re-allocation. When the traffic load brought by some specific classes under dynamic traffic conditions in a system exceeds the control range of DMS-AC, the QoS of some call classes may not be guaranteed. In such a situation, bandwidth re-allocation process is activated and the admission control scheme will try to meet the QoS requirements under the adjusted bandwidth allocation. We explore the relationship between admission thresholds and bandwidth allocation by identifying certain constraints for verifying the feasibility of the adjusted bandwidth allocation. We conduct extensive simulation experiments to validate the effectiveness of the proposed bandwidth re-allocation scheme. Numerical results show that when traffic pattern with certain bandwidth asymmetry between uplink and downlink changes, the system can re-allocate the bandwidth on uplink and downlink adaptively and at the same time improve the system performance significantly.     

流媒体在分组传送光网络PTN传输的动态带宽分配算法

根据光网络由SDH向分组化PTN网络演进及新兴流媒体业务的特点,本文采用混合业务流模型,引入门限控制,多级选择丢弃和多级缓存优先级的概念,提出了一种基于业务分类和业务优先级的带宽分配算法-基于门限的动态优先级带宽分配方案（TDPBA）,克服了门限控制分配带宽颗粒过大和优先级算法运算量较大的弊病,在特别定制的试验平台上进行了四优先级系统的网络性能仿真,验证了此方案可以最大限度的保障高优先级业务的传输,可以用于对QoS有较高要求的业务,适合引入处在分组化进程中的光网络,在现有网络上更有效的承载流媒体业务.     

An Adaptive Bandwidth Allocation for Energy Efficient Wireless Communication Systems

In this paper, an energy efficient bandwidth allocation scheme is proposed for wireless communication systems. An optimal bandwidth expansion (OBE) scheme is proposed to assign the available system bandwidth for users. When the system bandwidth does not reach the full load, the remaining bandwidth can be energy-efficiently assigned to the other users. Simulation results show that the energy efficiency of the proposed OBE scheme outperforms the traditional same bandwidth expansion (SBE) scheme. Thus, the proposed OBE can effectively assign the system bandwidth and improve energy efficiency.     

一种适于卫星IP广播网中的带宽分配策略

提出了一种适用于卫星IP广播网络的带宽分配策略。与现有的带宽分配策略相比,该策略采用的保证带宽分配和动态带宽分配相结合的方法,可以最大限度地利用系统的剩余带宽,提高了系统的带宽利用率。这种带宽分配策略是通过令牌桶算法实现的,实现起来比较简单,并可以和基于业务类别的服务质量保证机制结合起来使用。通过OPNET建模仿真,结果表明这种算法不但能对链路的总带宽进行预分配,还能对链路的剩余带宽实时地进行动态分配,实现了基于用户的服务质量的保证。     

一种基于无线多媒体业务的可升降级QoS动态带宽分配与优化策略

无线多媒体网络中的业务包括话音、流媒体、交互类和背景类业务4种，除话音业务外其余3种业务都是可变比特速率业务。对该网络用户资源分配（主要是带宽的分配）若采用传统的固定分配方法，必定陷入资源利用率低下和用户QoS得不到保障的两难境地。该文提出了一种基于无线多媒体业务的动态带宽分配与优化策略，在保证用户QoS的前提下，尽可能提高资源利用率。该文分别从网络和用户两个角度考虑，通过系统容量、业务阻塞率、数据延迟、流媒体的实际传输比和VBR业务综合服务等级等参数，对可升降级QoS无线多媒体网络进行了仿真分析，结果表明，对比传统的网络资源管理策略，该策略大大改善了系统的性能，提高了系统资源利用率。     

FDMA/DAMA卫星通信网资源分配策略研究

FDMA/DAMA卫星通信网的资源分配过程是为满足卫星链路高效、可靠使用卫星资源的综合决策过程。地球站参数、卫星参数、载波调制编码方式和雨衰等都是影响高效、可靠分配卫星资源的重要因素。在综合分析多种影响链路可用性因素基础上,提出了适用于FDMA/DAMA卫星通信网的资源动态分配策略,并设计了具体的分配流程和软件实现方案。通过比较某系统优化前后的运行数据,测试验证了优化分配策略的有效性和科学性。     

Bandwidth allocation scheme for cyclic-service fieldbus networks

Field devices in factory automation and process control systems generate time-critical, periodic, and time-available data that share the bandwidth of one fieldbus network medium. This paper presents a bandwidth allocation scheme that is applicable to cyclic-service fieldbus networks. The bandwidth allocation scheme transmits time-critical data as soon as the server is available. Transmission of periodic data is scheduled such that the network-induced delay will not exceed the maximum limit allowed. The bandwidth allocation scheme restricts the packet length of time-available data to satisfy the delay requirements of time-critical and periodic data. The bandwidth allocation scheme not only satisfies the real-time transmission requirements of both time-critical and periodic data, but also fully utilizes the bandwidth resources of the fieldbus network. The validity of this bandwidth allocation scheme is examined through simulation     

Radio Resource Allocation for Scalable Video Services Over Wireless Cellular Networks

Good quality video services always require higher bandwidth. Hence, to provide the video services e.g., multicast/broadcast services (MBSs) and unicast services along with the existing voice, internet, and other background traffic services over the wireless cellular networks, it is required to efficiently manage the wireless resources in order to reduce the overall forced call termination probability, to maximize the overall service quality, and to maximize the revenue. Fixed bandwidth allocation for the MBS sessions either reduces the quality of the MBS videos and bandwidth utilization or increases the overall forced call termination probability and of course the handover call dropping probability as well. Scalable video coding (SVC) technique allows the variable bit rate allocation for the video services. In this paper, we propose a bandwidth allocation scheme that efficiently allocates bandwidth among the MBS sessions and the non-MBS traffic calls (e.g., voice, unicast, internet, and other background traffic). The proposed scheme reduces the bandwidth allocation for the MBS sessions during the congested traffic condition only to accommodate more calls in the system. Instead of allocating fixed bandwidths for the MBS sessions and the non-MBS traffic, our scheme allocates variable bandwidths for them. However, the minimum quality of the videos is guaranteed by allocating minimum bandwidth for them. Using the mathematical and numerical analyses, we show that the proposed scheme maximizes the bandwidth utilization and significantly reduces the overall forced call termination probability as well as the handover call dropping probability.     

一种消除空闲时间的EPON信道传输方案

动态带宽分配算法是以太网无源光网络系统的关键技术之一,现有采用周期轮询机制的动态带宽分配算法大多存在轮询周期间时隙浪费的问题.文章提出了一种新的消除空闲时间的信道传输方案,理论分析和教值计算证明:新的方案可以有效地消除空闲时间,提高上行链路的利用率.