APON:宽带接入的方案之一

８月中旬,Ａｇｅｒｅ　Ｓｙｓｔｅｍ　、华 为、武汉邮科院、北邮电信在京联合举办了无源光网络（ＰＯＮ）研讨会。ＰＯＮ分为ＡＰＯＮ（ＡＴＭ－ＰＯＮ）、ＧＰＯＮ（Ｇｌｏｂａｌ　ＰＯＮ）和ＥＰＯＮ（Ｅｔｈｅｒｎｅｔ　ＰＯＮ）等,由于国内主要以ＡＰＯＮ研发与应用为主,因此会上也着重介绍了ＡＰＯＮ在宽带接入网中的应用。目前,电信运营公司在最后一公里宽带接入的解决方案中,有基于铜线ｘＤＳＬ（ＨＤＳＬ、ＡＤＳＬ、ＶＤＳＬ）、Ｃａｂｌｅ　Ｍｏｄｅｍ　和ＬＡＮ接入、基于光纤的ＡＰＯＮ、以及高速固定无线接入ＬＭＤＳ等…     

INFORMATION FOR AUTHORS

ＩＮＦＯＲＭＡＴＩＯＮＦＯＲＡＵＴＨＯＲＳ￥／／ＳＥＭＩＣＯＮＤＵＣＴＯＲＰＨＯＴＯＮＩＣＳＡＮＤＴＥＣＨＮＯＬＯＧＹ（ＳＰＡＴ）ｉｓｐｕｂｌｉｓｈｅｄｑｕａｒｔｅｒｌｙｗｉｔｈｔｈｅｐｕｒｐｏｓｅｏｆｐｒｏｖｉｄｉｎｇｔｈｅｐｕｂｌｉｃａｔｉｏｎｏ...     

光接入网：第五讲 光接入网的演进

本讲首次简要讲述光接入网升级的一般考虑，然后着重介绍无源光网络（ＰＯＮ）传送图像业务的主要方案，接下来进述ＰＯＮ为基础ＳＤＶ业务和应用以及ＳＤＨ在接入网中的应用，最后讲述以ＡＴＭ为基础的宽带ＰＯＮ（ＡＰＯＮ）。     

理想的光纤接入方案——APON技术

介绍了一种基于ＡＴＭ无源光网络（ＡＰＯＮ）技术的光纤接入方案,给出了ＡＰＯＮ系统的结构、工作方式。对照ｘＤＳＬ技术讨论了 ＡＰＯＮ的优良特性。文中还综合各种因素,分析了ＡＰＯＮ系统的可实现性及发展前景。     

FTTH—0512系统在CATV中的应用

目前光纤接入网发展很快,形式多种多样。ＦＴ－ＴＨ－０５１２系统是在光纤用户环路（ＦＴＴＬ）技术的基础上开发而成的,它可提供电话业务、数据业务、ＣＡＴＶ业务及其他宽带业务。该系统主要由中央局接口单元（ＣＯＩＵ）、光网络单元（ＯＮＵ）、无源光网络（ＰＯＮ）及ＯＡＭ系统等４个主要部分组成,ＦＴＴＨ－０５１２系统结构如图１和图２所示。 其中ＣＯＩＵ是ＦＴ－ＴＨ－０５１２系统与交换机的接口设备;ＯＮＵ是ＦＴＴＨ－０５１２系统与用户的接口设备;ＰＯＮ是ＣＯＩＵ和ＯＮＵ之间的光分配网络;ＯＡＭ系统负责日常维护…     

高效的OSPF网络设计的讨论

ＯＳＰＦ（开放最短路径优先）标准定义了这样一种协议：它被高端多协议路由器使用,用来交换一个网络的物理拓扑结构信息。ＯＳＰＦ描述了一类信息称之为连接状态公告（ＬＳＡ）,它允许路由器相互更新它们所连接的ＬＡＮ／ＷＡＮ链路。当网络中发生了一个变化,ＬＳＡ将...     

Coupler WDM智能制造系统投入商用

Ｃｏｕｐｌｅｒ（光分路器）和ＷＤＭ（光波分复用器）智能制造系统目前在上海交大问世,并于上海嘉慧光电子技术有限公司（ｈｔｔｐ／／ｗｗｗ．ｊｏｉｎｗｉｔ．ｃｏｍ．ｃｎ）投入批量生产。ＷＤＭ是光纤通信网络中的核心器件,是ＩＰｏｖｅｒＷＤＭ的基础。ＥＤＦＡ＋ＷＤＭ是光网扩容最经济有效的方案,在发达国家已得到广泛应用。Ｃｏｕｐｌｅｒ（光分路耦合器）则在ＳＤＨ＋ＰＯＮ、ＡＴＭ＋ＰＯＮ及光纤ＣＡＴＶ的ＨＦＣ网中发挥重要作用。嘉慧公司ＦＢＴ系统是以熔融拉锥方式制造全光纤器件,效率高,成本低,据悉为国内最先推出的…     

新型宽带接入网络ATM—PON

一、ＡＴＭ一ＰＯＮ的引入 随着用户对业务种类的需求越来越多,电信网向着宽带化多媒体化发展,接入网成了电信网的瓶颈,为此人们提出了许多方案来解决这个问题,如以现有铜线为基础的 ｘＤＳＬ（包括 ＨＤＳＬ,ＡＤＳＬ,ＶＤＳＬ）,光纤同轴混合网（ＨＦＣ）等。而最有前途的是光纤接入网,目前多采用一种较为可行的方案是无源光网络（ＰＯＮ）,其初期主要支持２Ｍｂｉｔ／ｓ以下速率的业务,适应于单向分布业务（如电视和广播节目）以及电话和窄带ＩＳＤＮ业务。但传统的ＰＯＮ结构存在如下缺点： 每个用户用于交互业务的带宽受到限…     

摄录编设备常见单词与缩写(续)

ＮＯＮＤ（ＮｅｕｔｒａｌＤｅｎｓｉｔｙ）中性密度ＮＤＦ（ＮｏｎＤｒｏｐＦｒａｍｅ）非失落帧ｎｏｎｌｏｃｋ非锁定ＮＯＲＭ（ｎｏｒｍａｌ）标准ＮＲ（ＮｏｉｓｅＲｅｄｕｃａｔｉｏｎ）降噪ｏｆ关ｏｕｔｐｕｔ输出ｏｖｅｒ过多Ｐｐａｕｓｅ暂停ＰＢ（ｐｌａｙｂ...     

无源光网技术分析

文章在描述了无源光网（ｐａｓｉｖｅｏｐｔｉｃａｌｎｅｔｗｏｒｋ）的网络结构后,对ＰＯＮ的几种组网方案（ＴＤＭ／ＴＤＭＡ、ＷＤＭ和ＳＣＭＡ）进行了分析,然后着重从经济的角度分析了ＰＯＮ的器件技术,最后对网络升级策略进行了讨论。     

Achieving Global Consensus on the Strategic Broadband Access Network — the Full Service Access Network Initiative

The Full Service Access Network (FSAN) initiative represents nearly half of the world's telephony lines. They have agreed upon a common broadband access system that can be applied to both the business and residential market sectors. The FSAN initiative has been responsible for harmonising the broadband requirements of many telcos; for example, it has produced the world's first asynchronous transfer mode passive optical network (ATM PON) specification which is being adopted world-wide. This paper describes the current activities within FSAN, the application of FSAN components and the future for FSAN.     

FSAN OAN-WG and future issues for broadband optical access networks

Network operators are aiming to provide a broadband access network to facilitate the next-generation telecom services. They have established the Full Services Access Networks (FSAN) group in order to find the best way to achieve early and cost-effective deployment of broadband optical access systems. They concluded that a single worldwide broadband access system should be investigated in the FSAN and then standardized in the international standards bodies such as the ITU-T. This article outlines the FSAN organization and the study targets for its Optical Access Network working group, and some key future study issues in terms of optical distribution network requirements and the required system functionalities of the B-PON system. It also describes its standardization strategy and the interaction between the FSAN and ITU-T     

Efficient medium arbitration of FSAN‐compliant GPONs

The steadily rising demand for multimedia and data services, the falling cost and omnipresence of Ethernet and the maturity of passive optical networks (PON) technology, promise to radically change the landscape in the local loop. The heart of a gigabit PON system (recently standardized by FSAN/ITU) is the medium access controller (MAC), which arbitrates access to the upstream link among users with fluctuating traffic demands and effects the multiplexing and concentration policy. At the same time, it has to safeguard the service quality and enforce the parameters agreed in the service level agreements (SLAs) between the users and the service provider. In this paper, a MAC protocol designed to serve any mix of services according to their quality of service (QoS) needs, employing four priority levels along with a high number of logically separate data queues is presented. The architecture and implementation in hardware of a MAC algorithm capable of allocating bandwidth down to a resolution of a byte with QoS differentiation is the focus of this paper. It employs the bandwidth arbitration tools of the FSAN/ITU G.984.3 standard and maps SLA parameters to GPON service parameters to create an efficient, fair and flexible residential access system. Copyright © 2005 John Wiley & Sons, Ltd.     

基于以太无源光网络的有线电视全业务接入系统

目前有线电视网开展双向业务主要是通过HFC Cable Modem方式,基于以太无源光网络(EPON, Ethernet Passive Optical Network)的有线电视全业务接入系统是可以实现传输包括模拟电视信号在内的全业务接入网(FSAN).分析了系统的结构、工作方式及特点,最后讨论了实现该系统的关键技术,该系统对有线电视网络进行双向化业务改造有重要参考价值.     

Dynamic resource allocation for quality of service on a PON withhome networks

Earlier efforts on optical access concentrated on the design of PONs for the collection and distribution portion of the access network. A possible evolution scenario for these types of access networks could be the SuperPON system. The SuperPON system exploits all possible upgrades of an FSAN APON system. In these networks the optical hardware is very simple, but a media access control protocol is needed for upstream traffic control. Even so, the role of communications is already well established in the office environment, thanks to networking innovations such as the Ethernet LAN. With the development of cheap, affordable broadband communications and the increasing complexity of consumer goods, it seems natural to extend the network into homes. As home area network application ever increases, we consider connectivity between the access network and the home network, which generates multiple traffic, in order to design a MAC protocol over the SuperPON access network with home networks. Global FIFO is quite simple, and allows dynamic upstream bandwidth allocation on the basis of a request-and-permit mechanism on the APON architecture. It has good bandwidth efficiency; however, being cell-based, it does not consider multiple traffic types from home networks. In this article we describe and analyze a new dynamic MAC resource allocation algorithm called multiple queue-FIFO that can achieve good performance under the SuperPON access network in the home network environment     

GPON与APON的比较研究

对全业务接入网(FSAN)的两种无源光网络(PON)技术GPON和APON做了介绍。通过线路编码、效率、帧封装格式等方面的对比，阐述了GPON技术的优势及其关键技术。GPON是APON的继承和发展。     

The Broadband Access Facility

The deployment of broadband access networks will revolutionise many aspects of society in the early years of the next millennium. Manufacturers, telecommunications providers and cable television operators world-wide are investing heavily on research into networks that provide broadband multimedia services to customers. BT has developed a prototype of a full service access network that can connect customers via optical fibre, digital subscriber line or radio technologies. This paper describes the physical implementation of the prototype network and the wide range of services that it can support.This prototype network, referred to as the 'broadband access facility' is enabling BT and its partners to understand the best access architectures for a given environment through practical testing. The network now serves as an experimental platform, that can be used for communicating broadband concepts, designing operational processes, developing management solutions and testing advanced applications.The full service access networks (FSAN) initiative is a collaboration involving fourteen of the world's leading telecommunications network operators and major equipment manufacturers. Its vision is to create a shared requirements specification for access systems supporting narrowband and broadband services. This common specification will mean that broadband network components can be developed for world markets, thus raising volumes and driving down unit costs. The common system specification is based around an ATM/SDH (asynchronous transfer mode/synchronous digital hierarchy) core network, with local optical fibre distribution via an ATM PON (passive optical network). DSL (digital subscriber line) systems maximise reuse of existing copper plant. The exact DSL system used depends upon where the optical system is terminated, e.g. in the local exchange, cabinet, kerb or home. Hence this broadband access system can support a range of access architectures — this flexibility is fundamental to the consensus achieved in FSAN.     

Efficient transport of packets with QoS in an FSAN-aligned GPON

The standardization of passive optical networks capable of transporting Ethernet frames at gigabit-per-second speeds, currently in progress in both ITU-T and IEEE, constitutes a major milestone toward cost-effective photonization of the last (aka first) mile. The article presents an Ethernet gigabit PON (GPON) system aligned with the philosophy of the evolving FSAN (full service access network) ITU-T specification, which focuses on the efficient support of any level of quality of service. The intelligence of this system, in terms of traffic quality guarantees, lies in the MAC protocol, which controls the distributed multiplexing/concentration function by allocating variable length slots to every user of the shared upstream (toward the network) medium. The way transport of information is organized in an ITU-T GPON system and the operation of a MAC protocol that preserves all QoS guarantees are presented and evaluated.     

NG-PON2技术方案研究

随着EPON、GPON的规模部署和10 Gbit/s PON标准的制定,FSAN组织已经启动了NG-PON2的标准化工作.本文将分析运营商对NG-PON2的技术需求,并对TDM-WDM-PON、WDM-PON 、OFDM-PON等多种备选技术方案进行探讨,研究这些技术的可实现性和与现有网络共存等问题.     

OA&M for full services access networks

A number of network operators and suppliers have collaborated in the full services access network (FSAN) initiative to agree on a common set of requirements for broadband networks. This article presents the OA&M requirements that have been considered by the OA&M working group with a view to reducing equipment and operational costs. In considering OA&M costs it is necessary to take into account both equipment costs and operational costs. The main principles presented for minimizing OA&M costs are: the use of standard interfaces and information models where possible; minimizing the need for special operational skills and maintenance tools; provision of accurate maintenance information by the system; promoting reuse by locating complex functions at common points to enable sharing of platforms; provision of functions for locating faults and detecting network degradation; and the need to build in the ability to evolve and upgrade the network and its management capability