EPON中ONU大规模软件升级技术研究与设计

如何快速稳定地对数量众多的ONU进行软件升级是EPON系统面临的一个重要问题,文章提出一种实现ONU软件批量升级、定时升级和自动升级的方法,它由OLT通过OAM协议发启ONU升级事件,然后ONU主动通过FTP(文件传输协议)完成文件下载、数据校验和程序烧写等操作步骤,同时OLT还需监控、维护和管理ONU软件升级的状态.     

10G EPON系统ONU注册技术研究(本期优秀论文)

ONU注册是10G EPON系统正常运行的前提,在不影响系统正常运行的情况下实现新ONU自动注册或故障ONU重新注册是PON系统的突出优点.文章分析了10G EPON系统的双速率MAC协议栈及10GEPON MPCP控制帧相对于1G EPON MPCP控制帧结构所作的扩展,描述了10G EPON系统ONU注册的基本流程,重点讨论了OLT开窗控制和ONU注册响应的基本原理.     

一种改进的EPON网络拓扑保护机制

本文分析了目前常用的几种EPON网络保护机制存在的问题,探讨了一种改进的EPON保护机制:分支环网+全光纤保护机制。通过Matlab仿真分析证明,这种保护机制比现行各种保护机制有更好的生存性。     

A cost-effective WDM-PON architecture simultaneously supporting wired, wireless and optical VPN services

It is believed that next-generation passive optical networks (PONs) are required to provide flexible and various services to users in a cost-effective way. To address this issue, for the first time, this paper proposes and demonstrates a novel wavelength-division-multiplexed PON (WDM-PON) architecture to simultaneously support three types of services: 1) wireless access traffic, 2) optical virtual passive network (VPN) communications, and 3) conventional wired services. In the optical line terminal (OLT), we use two cascaded Mach-Zehnder modulators (MZMs) on each wavelength channel to generate an optical carrier, and produce the wireless and the downstream traffic using the orthogonal modulation technique. In each optical network unit (ONU), the obtained optical carrier is modulated by a single MZM to provide the VPN and upstream communications. Consequently, the light sources in the ONUs are saved and the system cost is reduced. The feasibility of our proposal is experimentally and numerically verified.     

EPON中上行时隙的动态分配

根据以太网数据包具有变长性的特点,描述了在以太网无源光网络(Ethernet Passive Optical Network,EPON)系统中局端光线路终端(Optical Line Terminal,OLT)根据终端用户的实际需求,动态分配给各个光网络单元(Optical Network Unit,ONU)上行时隙。动态时隙的分配能充分利用上行信道,大大减少了因为变长数据包不能完全适合固定时隙而带来的带宽浪费。     

基于TK3713芯片的EPON ONU硬件设计与实现

介绍了EPON系统构成以及ONU在EPON体系中的主要功能,提出了一种基于Teknovus公司专用处理芯片TK3713的ONU（光网路单元）设计方案,并对ONU主控芯片模块、以太网交换模块、光突发式收发模块、电源模块四大模块进行了重点分析,完成了EPON ONU硬件平台的设计和实现。经实际验证,该方案设计的ONU能够成功地实现＂三网合一＂并解决信息高速公路＂最后一公里＂问题。     

50 km bidirectional FTTH transmission comparing different PON standards

In this paper, a bidirectional Fiber To The Home (FTTH) is proposed where WDM transmitter is used as a seeding source with wavelength of 1550 nm. The system utilizes a Travelling wave Semiconductor Optical Amplifier (TSOA) with injection current 0.15A. 50 km range FTTH architecture is demonstrated for both downstream and upstream channels. We investigated the impact of different data rates on upstream and downstream data. The BER results show that the performance of our scheme is good for 10 Gbps system for downstream transmission as it accommodates 64 ONUs. From simulation results show the BER of 9.95e-009 is reported at 15 Gbps but only in case of 32 ONUs. Similarly, in case of upstream transmission, Q-Factor of 15.04 dB is reported for 32 ONUs. So this scheme is a practical solution to meet the data rate of the optical links simultaneously in tomorrow's PON access networks.     

光传送网分层结构及网络节点接口特征信息

标准人的网络节点接口信息结构是将来网络互通的基础。同时也为各设备生产商提供了标准的规范和设计依据。文章介绍了光传送网的分层结构和节点特征信息。     

张家港有线接入网双向改造规划方案

本文简要介绍了张家港在有线电视接入网中双向改造过程中,结合现有EPON及EoC产品的相关特性,对网络进行的系统规划。     

一种适合承载IPTV多播业务的新型EPON扩展网络架构

本文提出一种新型的EPON扩展网络架构,通过在原有OLT和ONU设备之间新增加一条无源光网络PON通道,该PON通道用于单独承载IP多播数据流,原PON通道仍可正常承载其他IP数据流。使得EPON网络在承载IPTV业务时,既能够保证实时多播业务质量要求又能够保证单播业务的带宽要求。本文同时描述了这种双PON通道的EPON扩展网络架构实现方法以及对支持双PON接口ONU的管理方式。