Using CSMA/CD for Ethernet Passive Optical Network (EPON)

Using CSMA/CD for EPON can eliminate the augmentations, such as multi-point control protocol and point-to-point emulation, added to the existing 802.3 architecture due to the incompatibility of PON to Ethernet. Both full-duplex EPON system and half-duplex EPON system using CSMA/CD were proposed. In the full-duplex EPON, CSMA/CD is used as the upstream MAC protocol. In the half-duplex EPON system, both upstream and downstream traffic contend for the optical channel through CSMA/CD protocol. The upstream lightwave redirection and collision detection techniques were given. By the analysis and simulation, the throughput performance of the half-duplex EPON system is proven to be as well as that of the existing high speed half-duplex Ethernet LAN.

Modeling for Ethernet passive optical network receiver

A behavior model for the receiver of the Ethernet passive optical network（EPON） is presented. The model consists of a fiber, a photodetector, a transimpedance amplifier （TIA） followed by a limiting amplifier and a clock and data recovery＇ circuit （CDR）. Each sub-model is constructed based on the architecture of a circuit. The noise and jitter in each block such as shot noise, thermal noise, deterministic and random jitter are also considered. The performance of the whole receiver can be evaluated by the simulation of the behavior model, which is faster than the ordinary circuit model and more accurate than the analytical model. The whole model is implemented with C ＋＋ and simulated in Microsoft Visual C ＋＋ 6. 0. Using the Monte Carlo method, the EPON receiver is simulated. The simulation results show a good agreement with experimental ones.

Implementation of access controller for Ethernet passive optical network

This paper presents the design and implementation of access controller used for Ethernet passive optical network （ EPON）. As a first step to develop an ASIC product, the entire system is designed on a field programmable gate array （FPGA） with an embedded CPU. To reduce working frequency of the FPGA, the byte-to-word conversion is proposed. Propagation delays are equalized by ranging procedure so as to avoid data collision. Implementations of synchronization, classification, as well as Linux porting are illustrated in detail. The interface between the FPGA and CPU are also presented. Experimental results show that the proposed system can properly function in a relatively low cost FPGA.

A novel algorithm for Ethernet-passive-optical-network dynamic bandwidth allocation based on threshold

The Ethemet passive optical network （EPON） is the next generation of broad-band network technique. A crucial issue in EPONs is the sharing of uplink bandwidth among optical network units （ONUs）. This article provides a novel dynamic bandwidth allocation algorithm, i.e. threshold dynamic bandwidth allocation （TDBA）, which is based on adaptive threshold, to increase resource utilization. The algorithm uses ONU data-transmitting rate to adjust optical line terminal （OLT） receiving data threshold from an ONU. Simulation results show that this algorithm can decrease average packet delay and increase network throughput in a l 0G EPON system.

QoS Guaranteed and Adaptive Downstream Bandwidth Utilization Scheme for Ethernet Passive Optical Networks

Dynamic bandwidth allocation（DBA） is an open and hot topic in the Ethernet passive optical network（EPON） ,which is regarded as one of the best choices for next-generation access networks. However,most proposed DBA schemes ignore the quality of service（QoS） guarantee on maximum delay and delay jitter for the real-time traffic and the downstream bandwidth utilization under light upstream load in EPON. In this paper,a new DBA scheme,QoS guaranteed adaptive downstream bandwidth utilization（QoS-ADBU）,is proposed. This scheme can provide better QoS assurance by determining the maximum transmission cycle time according to the maximum acceptable packet delay and delay jitter for real-time traffic. Besides,the downstream utilization can also be improved by adapting the polling frequency to downstream traffic load.

Echo-state-network classification based multi-services awareness in high-speed optical passive networks

With the challenge of great growing of services diversity,service-oriented supporting ability is required by current high-speed passive optical network( PON). Aimed at enhancing the quality of service( Qo S) brought by diversified-services,this study proposes an echo state network( ESN)based multi-service awareness mechanism in 10-Gigabite ethernet passive optical network( 10GEPON). In the proposed approach,distributed architecture is adopted to realize this ESN based multi-service awareness. According to the network architecture of 10G-EPON,where a main ESN is running in OLT and a number of ESN agents works in ONUs. The main-ESN plays the main function of service-awareness from the total view of various kinds of services in 10G-EPON system,by full ESN training. Then,the reservoir information of well-trained ESN in OLT will be broadcasted to all ONUs and those ESN agents working in ONUs are allowed to conduct independent service-awareness function. Thus,resources allocation and transport policy are both determined only in ONUs. Simulation results show that the proposed mechanism is able to better support the ability of multiple services.

Design and implementation of ethernet passive electronic network over coax

To increase the limit of ethernet over coax （EoC） technology in the bidirectional reform of the hybrid fiber coaxial （HFC） network, an ethernet passive electronic network （EPEN） system based on Coax is proposed and experimentally demonstrated in this paper. The proposed EPEN exploits the existing capabilities of the MAC layer in the ethernet passive optical network （EPON） for reduction of cost of the HFC network. As the MPCP （multi-point control protocol） is introduced in the EPEN, bandwidth control and higher efficiency can be achieved. The experimental results exhibit the throughput of system up to 100Mbps, which meet the requirements of HFC network. To improve the performance of EPEN, frequency division multiplexing （FDM） can be used for further increase of the throughput and more hardware processing modules in the future. can be implemented to enhance the capacity

Upstream Channel Utilization of CSMA/CD-Based Ethernet over Passive Optical Networks

We demonstrate that an asynchronous CSMA/CD protocol with an optical loop-back star coupler can achieve high upstream channel utilizatbn in an Ethernet PON, readily supporting a large installed base of Ethernet 10BaseT and 100BaseT interfaces.

基于EPON通信网络的10kV线路差动保护技术研究

以太网被动光网络(Ethernet Passive Optical Network,EPON)技术由于其高带宽、低延迟的特性,成为一种适合电力系统通信的技术平台。文章详细探讨基于EPON通信网络的10 kV线路差动保护技术的设计与实现,从EPON网络架构的搭建、网络参数的优化配置,到仿真模型的建立和实验验证。文章还包括差动保护策略的设计、系统现场试验与数据分析,以全面评估该技术在实际应用中的表现和效益。

Dynamic Wavelength and Bandwidth Allocation Using Adaptive Linear Prediction in WDM/TDM Ethernet Passive Optical Networks

Hybrid wavelength-division-multiplexing(WDM)/time-division-multiplexing(TDM) ethernet passive optical networks(EPONs) can achieve low per-subscriber cost and scalability to increase the number of subscribers. This paper discusses dynamic wavelength and bandwidth allocation(DWBA) algorithm in hybrid WDM/TDM EPONs.Based on the correlation structure of the variable bit rate(VBR) video traffic,we propose a quality-ofservice (QoS) supported DWBA using adaptive linear traffic prediction.Wavelength and timeslot are allocated dynamically by optical line terminal(OLT) to all optical network units(ONUs) based on the bandwidth requests and the guaranteed service level agreements(SLA) of all ONUs.Mean square error of the predicted average arriving rate of compound video traffic during waiting period is minimized through Wiener-Hopf equation.Simulation results show that the DWBA-adaptive-linear-prediction(DWBA-ALP) algorithm can significantly improve the QoS performances in terms of low delay and high bandwidth utilization.

一种半双工EPON系统的性能分析(英文)

提出了改进的上行光环回技术和冲突检测技术以解决现有全双工CSMA/CDEPON方案中上行环回光功率损耗过大和冲突检测实现困难等问题 提出了一种半双工CSMA/CDEPON方案 通过理论推导和仿真验证 ,说明了虽然接入网系统中上 /下行业务量往往是高度不对称的 。

一种半双工EPON接入方案

提出一种通过在星型耦合器的网络侧插入光纤布喇格光栅 ,在用户侧增加一个远端转发单元的方法 ,将CSMA/CD用作多址接入协议的半双工EPON接入方案。理论分析与仿真实验表明其性能与 10 0BASE T局域网相当。该方案实现简单 ,成本低廉 ,与现有以太网的体系结构兼容。

Optical local area network emulations over Ethernet passive optical networks:A survey

As a promising solution to efficiently achieving fiber to the home （FTTH）, Ethernet passive optical network （EPON） is currently improved to provide intercommunication among customers, together with normal traffic delivery, via optical local area network emulation. It is a new research direction and expected to enhance the normal EPON performances. The purpose of this article is to review the state-of -the-art solutions to emulating optical local area networks （OLANs） over EPON. We discuss the major problems involved, e.g., network architecture, control mechanisms, and other potential enhancements. We also outline areas for future researches.

基于EPON通信的智能配电网馈线差动保护

智能配电网正朝着网格化、多电源的拓扑结构发展,传统配电网保护、馈线自动化(FA)已经越来越难以满足智能配电网自愈的要求。电流差动保护由于其优越的速动性、灵敏性和选择性而广泛地应用于输电线路,现有的方法是采用专用光纤通道或者基于同步数字系列/准同步数字系列(SDH/PDH)技术的复用通道来实现,但架设这些通信设备费用高且通信速率慢。文中提出并研制了一种适用于智能配电网的差动保护的装置,该装置基于以太无源光网络(EPON)来实现差动保护装置之间采样数据的传输,配以抗延时抖动及IEEE 1588同步算法,实现多端线路差动保护。测试表明,保护能够准确动作,满足精度和动作时间的要求。该装置已在某10 kV线路挂网运行。

矿区配电网自动化EPON通信的可靠性分析

矿区配电网自动化运行对矿山企业安全生产至关重要。针对现有的矿区配电网自动化通信网络在可靠性设计和网络系统容灾能力等方面的不足,研究了网络链路冗余度对矿区配电网自动化网络可靠性的影响,并构建了基于以太无源光网络(Ethernet Passive optical Network,EPON)的矿区配电网自动化网络可靠性模型。在此基础上,提出了基于树形、总线形和环形的矿区配电网自动化EPON网络冗余结构,并推导出相应的网络可靠性数学评估模型。基于MATLAB的算例计算结果表明:矿区配电网自动化中EPON通信网络的可靠性与灾害强度、网络覆盖半径及网络结构密切相关,灾害强度与网络覆盖半径越高,网络可靠性越低;采用冗余结构的EPON通信网络的可靠性优于无冗余网络,其中双总线形冗余结构的可靠性最高,双环形冗余结构的可靠性居中,而树形冗余结构的可靠性最低。研究成果可为矿区配电网自动化通信网络的可靠性评估提供理论依据。

配电通信网接入层EPON保护组网可靠性与性价比分析

在通信网可靠性分析理论的基础上,提出了针对配电通信网接入层以太网无源光网络(EPON)保护组网方式的网络可靠性分析方法。采用系统可用度理论,定量分析研究了单电源冗余保护树形网、全链型保护手拉手网、全链路保护双电源双T网、环形保护网等几种配电通信网接入层EPON保护组网方式的可靠性,并对组网成本进行了分析。讨论和总结了当前实施中的配电通信网建设和改造工程EPON保护组网的最优组网方案。

EPON与EOC技术在广电系统中的应用与发展

简单描述当前有线电视网络运营商接入网部分的带宽资源与面临的问题,介绍EPON与EOC两种新技术的内容与特点,并结合具体网络模型与实际应用实例解析两种新技术在有线广播电视网络系统运维和解决接入网带宽问题上的优势,最后根据当前有线电视网络发展现状指出这两项技术在未来的发展前景。

智能变电站过程层网络采用EPON技术实用性研究

本文提出在智能变电站过程层网络通信系统采用EPON进行组网的应用方案,在对智能变电站过程层通信业务分析、及EPON技术和现阶段智能变电站过程层所采用的主流工业以太网技术进行对比分析的基础上,围绕重点关注的SV采样值传输性能及GOOSE传输性能,搭建模拟系统,利用网络记录及分析系统对智能变电站过程层采用EPON组网后的SV传输离散度、GOOSE传输时延进行了分析,分析结果表明在智能变电站过程层采用EPON通信技术不能满足SV和GOOSE的应用需求,本文研究工作是智能变电站及智能电网建设极具现实意义的探索。

基于NS2的EPON网络建模——结构和性能分析

针对以太网无源光网络的网络规划和算法研究,在IEEE802.3ah标准的基础上,通过扩展开源网络模拟程序Network Simulator Version 2(NS2),完成对以太网无源光网络(EPON)的建模与测试,实现了光网络单元(ONU)注册、测距、带宽分配、服务质量(QoS)等诸多功能,为EPON网络规划和算法研究提供了一个全面完整的仿真平台(EPONns).注册过程模拟给出成功注册的ONU数目与注册窗口值的关系;光传输线路终端(OLT)负载状况检测反映出EPONns在高负荷下的状态.