System and cost analyses of broad-band fiber loop architectures

Analyses of four broadband fiber-optic subscriber loop architectures, including active (high-speed time division multiplexing (TDM)-based) and passive (dense wavelength division multiplexing (WDM)-based, WDM-based with an analog subcarrier-multiplexing overlay, and splitter-based) double-star topologies, are presented. The analyses focus on specific demonstrated architectures and use component cost projections based on learning curves to estimate future network costs on a per-subscriber basis. Also investigated is the sensitivity of projected cost-per-subscriber to remote multiplexing node size and to double-star prove-in distance. The results indicate that the four architectures have very different double-star prove-in distances and that loop costs are minimized for much smaller remote node sizes than active loops, thus permitting cost-effective deployment of passive loops for smaller groups of subscribers. In addition, cost breakdowns for the four architectures indicate that splitter-based passive loops share electronics more effectively among subscribers than loop architectures requiring dedicated (per-subscriber) electronic interfaces, resulting in projected cost advantages for the splitter-based networks     

A star-configured fiber-to-the-curb system

Fiber-to-the-curb (FTTC) system proposals have arisen because of the present high cost of fiber-to-the-home (FTTH) systems. With FTTC systems, fiber is brought only as far as the service access point (SAP). From there, copper drops carry signals from the SAP to several residences. Owing to the extensive sharing of optical sources and the fibers running to the SAP, the per-subscriber system cost is greatly reduced relative to the per-subscriber cost of a FTTH system. In addition, elimination of the optical network unit (ONU) at the home may offer new options for powering and battery back-up. This paper presents an analysis of a star-configured, fiber-to-the-curb distribution network that serves up to ninety-six customers, initially providing two plain old telephone service (POTS) channels to each customer. Three system variations, serving either four, six, or eight customers per SAP, are examined. We also estimate the installed first costs (IFC) of the distribution link (remote node to customer) for the three FTTC scenarios and compare them to the IFC of a FTTH system with similar capabilities. Star-configured FTTC architectures can be installed for substantially less ($1180-$825/customer for four to eight customers per SAP) than the estimated $2920 per subscriber cost associated with FTTH systems. Finally, we propose an upgrade strategy, consistent with the passive photonic loop (PPL) network, to support future high bandwidth services.     

Economics of residential broadband access network technologies andstrategies

This article presents a techno-economic assessment of the evolution of the access network segment toward broadband data service delivery, including in-depth sensitivity analysis of key issues faced by the infrastructure providers. The line costs and payback periods of different access network technologies for infrastructure broadband upgrades are examined, subject to variation in parameters like the existing infrastructure, the broadband take rate, civil work costs, revenues, and rollout year. The work should enable establishment of guidelines for broadband infrastructure upgrade strategies     

Architecture for delivery of broadband services to the residence

This paper presents a technology and architecture perspective on the cost of evolving today's copper access network, optimized for POTS, to a fibre access network providing both narrowband and broadband services. Architectures are assessed using application studies based on cost models for actual routes in North America. This study identifies three architectures as serious candidates (i.e. close to copper in cost) for providing POTS service in 1992: the double star, the active pedestal and the star-bus. The active pedestal and the star-bus architectures were similar in first costs and were the least expensive, costing between 5 and 15 per cent more than the copper reference depending on the number of subscribers subtending a given optical fibre. The double star is 20 per cent more expensive than the copper reference. All three architectures are potentially attractive for broadband service upgrade depending on the bandwidth required per subscriber. The star-bus is most bandwidth sensitive. Moderate video bandwidths, nominally 150 Mb/s/subscriber, favour the active pedestal architecture. Conversely, service environments requiring much greater than 150 Mb/s/subscriber favour the double star architecture.     

Crossing the digital divide: cost-effective broadband wireless access for rural and remote areas

The use of wireless, DSL, and cable for broadband access has become increasingly prevalent in metropolitan areas. While these technologies are being successfully utilized in terms of both service quality and economics in densely populated areas, there are still vast geographic regions where broadband services are either prohibitively expensive or simply unavailable at any price. The article examines several alternatives for using 2.4 GHz 802.11b (WiFi) technology to provide fixed broadband access in rural areas consisting of towns, smaller remote communities, clusters of subscribers separated by large intercluster distances, as well as widely scattered users. Our approach is to model a network based on realistic demographics, equipment and operations costs, service revenues, and customer demand and usage, and calculate the lifecycle economics in terms of capital investment and profitability. We consider the cost benefits of several emerging technologies and architectures, including high gain antennas, dynamically steerable beamforming antennas, and multihop routing. Our results show that cost-effective affordable high-speed wireless Internet access can be provided in rural and remote areas using nontraditional and innovative approaches, bridging the so-called digital divide.     

有线电视双向网接入技术选择

EPON技术因其高带宽、无源分配、易维护、支持多业务等优势,近年来正在成为宽带接入的主要技术之一,也非常适合于有线电视网络开展双向数据业务。在接入技术方面有EoC、LAN,部分广电有线电视网络已经进行了基于Cable Modem方式的HFC双向网改造,那么如何选择宽带接入方式呢？对HFC、EPON以及几种接入技术做技术分析、投入成本分析以及网络现状分析,以此选择适合有线电视网宽带接入的技术方式。     

HFC Access Network Design for Switched Broadcast TV Services

The hybrid fiber coax (HFC) is a modern broadband access network, providing advanced interactive services such as Internet access, digital interactive television and cable telephony. The edge costs dominate the cost of launching new services, at the time of deployment (CapEx) as well as for maintenance (OpEx). Therefore next-generation edge devices aim at the convergence of these services and their platforms into a single multi-service infrastructure, thus sharing resources and bandwidth. The focus of this paper is on the HFC access network design for bandwidth-intensive TV services, bringing standard as well as switched broadcast technologies into play. Standard broadcast TV service deployments, offered through the digital video broadcast (DVB) platform, require low installation costs, but the bandwidth consumption increases linearly with the number of available TV channels, even for very unpopular channels. Switched broadcast TV channels, offered on the (Euro-) DOCSIS platform together with other interactive unicast services such as video on demand, are only streamed to a node on the HFC access network if they are requested locally, thus limiting bandwidth consumption for less popular channels. We present an access network design tool, based on an analytical TV traffic model, minimizing the installation cost on the edge devices and study the influence of the most important traffic and content parameters.     

室外Wi-Fi网状网在农村的发展和应用

基于Wi-Fi的室外无线网状网因具有高带宽、低价格、可扩展、易维护等优势.近年来在热点覆盖、无线城市等领域的应用迅速发展,其低成本优势也使室外无线网状网成为农村无线宽带覆盖的最有竞争力技术之一.中国科学院计算技术研究所在北京怀柔区渤海镇北沟成功地建设了一个覆盖130多个用户的无线网状网.本文讲述在建设中遇到的问题与积累的经验,以及关于建设宽带Wi-Fi乡村的技术和商业问题的探讨.由于用户需求的刚性,作者认为在农村发展宽带无线网络比无线城市更有优势.     

可生存光纤—无线融合宽带接入网规划方法

光纤—无线融合（fiber-wireless,FiWi）宽带接入网的出现不仅为随时随地的灵活宽带接入提供了新的技术参考,同时也为可生存宽带接入网的低成本设计增加了研究契机。研究了可生存FiWi接入网的网络规划问题,提出一种基于无线重路由保护的可生存网络规划方法。当任意光纤链路断裂时,失效的光网络单元可通过无线重路由将业务转移到其他可用的光网络单元承载。重点解决了无线路由器部署、备份射频接口配置及光网络单元容量分配的联合优化问题,目标是通过最小化网络部署成本实现业务的完全保护。采用整数线性规划方法获得了小规模网络规划问题的最优解,同时提出了适用于大规模网络规划问题的启发式算法。仿真结果证实了所提方法在降低网络部署成本方面的有效性。     

Fixed Mobile Convergence Architectures for Broadband Access: Integration of EPON and WiMAX [Topics in Optical Communications]

EPON and WiMAX are two promising broadband access technologies for new-generation wired and wireless access. Their complementary features motivate interest in using EPON as a backhaul to connect multiple dispersed WiMAX base stations. In this article we propose four broadband access architectures to integrate EPON and WiMAX technologies. The integrated architectures can take advantage of the bandwidth benefit of fiber communications, and the mobile and non-line-of-sight features of wireless communications. Based on these integrated architectures, we elaborate on related control and operation issues to address the benefits gained by this integration. Integration of EPON and WiMAX enables fixed mobile convergence, and is expected to significantly reduce overall design and operational costs for new-generation broadband access networks.     

Broadbandloop: a full-service access network for residential andsmall business users

There is a worldwide effort to define a full-service access network. The Broadbandloop project was formed by a European consortium funded by the European Union with the objective of defining a strategy for evolution from a narrowband voice and data network to a broadband network. The project is defining a system concept based on new innovative PON technology, which enables fiber to cost effectively penetrate close to the customer, and VDSL technology for transmission over twisted copper pairs. The system concept is validated in field trials in Denmark, Portugal, and Poland. The article describes the different requirements for a full-service access network, the system concept, and technologies developed. Results from modeling of broadband traffic and the corresponding bandwidth are given. The cost effectiveness of using new optical fiber vs. reusing existing telephone copper plant has been evaluated, and results from these studies are presented     

EPON技术在边远地区宽带接入中的应用

为了实现边远地区村村通宽带的目的,采用一种新型的光纤接入网EPON技术接入法,做了多次边远地区EPON接入模式应用试验,获得农村边远地区宽带、电话、IPTV等现有业务接入的结果,得到在光纤资源短缺的情况下,EPON技术是实现农村边远地区宽带接入的最佳解决方案的结论;EPON接入模式具有运营与维护成本低、易于维护、扩充性好、业务丰富等特点。     

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.     

WiMAX应用潜力分析

文章分析了WiMAX在固定宽带无线接入场合和便携、移动通信场合的应用前景.文章认为:在固定宽带无线通信中,WiMAX会广泛应用于家庭用户、IP语音用户、传输承载用户和集团客户,为他们提供宽带无线接入;在便携、移动通信中,IEEE802.16即将集成到笔记本电脑和个人数字助理(PDA)等便携式电子设备中,实现在城域网范围内的可移动的宽带无线数据服务;用户需求加上WiMAX设备的批量上市及终端成本的下降,WiMAX的应用潜力巨大,市场将呈几何级增长.     

Parametric methodology for analyzing implementation strategies ofresidential broadband networks: the incremental cost of integratedaccess

An engineering framework for estimating the investment cost of two implementation strategies intended to provide broadband (video services) access to residential customers in new construction areas is described. One strategy is the deployment of a single (digital and fiber) integrated network, and the other is the codeployment of dual, separate networks (one for narrowband and the others for TV distribution). The methodology derives the investment per subscriber as a function of network element's costs and demographical, topological, and service penetration parameters. The methodology is applied to TELEFONICA's network. The incremental cost of the integrated network (compared with dual networks codeployment) is estimated to be around $700 per customer. The results highlight the importance of broadband services that would not be fully provided by conventional cable TV distribution networks     

Cost models for QoS-differentiated interconnecting and wholesale access services in?future generation networks

Currently, network operators and Internet service providers are offering ??Triple Play?? products integrating services with different Quality of Service (QoS) requirements. It is leading to Internet traffic with strong service integration under an all-IP-based broadband network platform. However, new multimedia service offers require individual QoS guarantees for each type of services. The interconnection between different providers necessitates the reconsideration of the actual cost schemes. Interconnection and wholesale access services (It is an extension of ??wholesale network?? definition, where Telco??s physical network and equipment are ??shared?? to many independent Service Providers. If the incumbent offers broadband access services, the rest of the alternative providers have recourse to the incumbent??s ??wholesale access service??. Bitstream service is the most important service of this type, actually regulated over DSL and cable networks.) appear to be a simple solution, but the consideration of QoS parameters requires an extension of the current network dimensioning methods based mainly on the average bandwidth demand from each user. This paper proposes a cost model which considers QoS parameters and, based on the ??Total Element based Long Run Incremental Cost?? (TELRIC) model, is applied to the wholesale access and interconnection paradigm. Three traffic engineering methods are considered and studied for network dimensioning. Hereby the aim is to guarantee the QoS of the different services: complete traffic segregation under virtual tunnels, complete traffic integration by over-engineering and partial traffic integration using a priority queuing scheme. The proposed method enables the development of a specific cost scheme based on a complete scenario considering different types of users. The variety of used IP applications suppose direct implications over different levels of interconnection, mainly at the low-level Metro access and the high-level edge node.     

Optimal placement and channel assignment of relay stations in heterogeneous wireless mesh networks by modified Bender’s decomposition

Fixed Broadband Wireless Access (FBWA) technology is designed to serve as a wireless DSL replacement to provide broadband Internet access in underserved areas where no other access technology exists. Due to the enormousness of the target service area, relay equipment play an important role in such networks, and the installation and maintenance cost of the network is directly proportional to the cost of the relay equipment. To minimize the network operational cost, an optimization framework which computes the minimum number of relay stations and their corresponding placements and channel assignments in the network is desired. Because the problem is NP-hard, we propose an efficient optimization algorithm based on a modified version of Bender’s decomposition to iteratively compute converging bounds to the problem solution. Our numerical results show that by using a few relay stations in a rural community, broadband Internet access can be established in a cost effective manner.     

新一代的以太接入网

接入网是一个公共的网络环境,应用以太网技术需要解决用户信息隔离、用户管理和业务保证等问题。目前的以太网接入解决方案存在不少问题。适于公共网络环境的新一代以太接入网方案具有高度的信息安全性和强大的网管功能,可以保证用户的接入网方案具有高度的信息安全性和强大的网管功能,可以保证用户的接入带宽,而且成本低廉,将在今后的宽带接入中发挥重要作用。     

Fiber-Based Broadband-Access Deployment in the United States

After more than 20 years of research and development, a combination of technological, regulatory, and competitive forces are finally bringing fiber-based broadband access to commercial fruition. The three main approaches-hybrid fiber coax, fiber to the cabinet, and fiber to the home-are each vying for dominance in the industry, and each has significant future potential to grow customers and increase bandwidth and associated-service offerings. Further technical advances and cost reductions will be adopted, eventually bringing performance levels and bandwidth to gigabits-per-second rates when user demand warrants while keeping service costs affordable     

GSM900M频段的宽带接入技术

比较了现有的几种无线宽带接入方式，介绍了一种利用GSM900M频段采用OFDM调制技术来实现无线宽带接入的方案原理以及实际测试结果，并给出了此种方案的配置原则。