IP/ATM integrated services over broadband access coppertechnologies

A rich set of broadband access copper technologies is available in the market today, and more are coming out of the laboratories, rapidly moving to standardization. The most likely future scenario will be one where many different technologies coexist. This multi-access-technology paradigm poses an interesting internetworking problem where interoperability and capability to support today's and future user services play a major role in the design of a network architecture. This article begins with an overview of current and new xDSL access technologies to continue describing an access network design that harmonizes the interconnection between PON, xDSL, and native ATM transport technologies. The use of ATM technology for the interface to the broadband access and transport networks is then presented and justified. The article continues studying the protocol architectures proposed for access to network service providers, considered a driver application for broadband access deployment. Finally, different protocol architectures that can provide integrated services support at the user equipment are analyzed     

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.     

Broadband wireless access

This article reviews the technologies and potential markets, applications, and architectures for broadband wireless access. The emergence of wireless communications for cellular systems is presented, together with its projected future evolution to mobile wideband systems. The field of broadband access systems, services, and network architectures is also covered, and then systems for broadband wireless communications for indoor local area networks and outdoor public fixed access networks are discussed. Broadband wireless access systems are emerging as a new and growing area of telecommunications, since the ability to provide access without extensive installation of copper or fiber infrastructures make wireless technology well suited for broadband services. Finally, some of the key enabling technologies, such as adaptive antennas and video compression, and the future architectural directions of broadband wireless networks are presented     

Telecommunications applications of integrated optics and optoelectronics

Integrated optics and optoelectronics will play key roles in the evolution of the telecommunications network. We briefly review the available and developing technologies for integrated optical and optoelectronic devices, and summarize their characteristics and their natural areas of application in telecommunications. We then describe the trends and developments in fiber communication systems, services, and architectures, and how they can benefit from these devices. Major areas in which these devices are expected to contribute are: lowering the costs of high-speed network termination equipment to aid in providing inexpensive wide-band services to the subscriber; increasing the fraction of the fiber's natural bandwidth that can be made available for network usage; and increasing the network flexibility to facilitate multiservice integration.     

Wireless Mesh Networks for In-Home IPTV Distribution

IPTV is considered to be the next killer application. A key, challenging issue is in-home IPTV distribution with affordable deployment cost and sufficient flexibility, scalability, and reliability. In this article, we first survey and compare the emerging wired and wireless communication technologies for broadband home networks, including transmission over power lines, phone lines, coaxial cables or Ethernet cables, and IEEE 802.1 In, ultra wideband and millimeter wave wireless technologies. Considering these promising candidates for future broadband home networks, we propose three wireless mesh network architectures. These enable consumers to enjoy anywhere, anytime IPTV services without rewiring their homes. We compare the cost, reliability, and scalability of the three architectures. We further study their admission regions for IPTV, that is, the number of IPTV connections that can be supported simultaneously with satisfactory QoS. Analytical and simulation results with H.264 HDTV sources over wired, single hop wireless, and multi-hop wireless paths are given. These results can provide important guidelines for future broadband home network design supporting IPTV services.     

Tree-type photonic switching networks

The enormous bandwidth offered by optical systems makes photonic switching a very attractive solution for broadband communications. Tree-type architectures play an important role in the design of photonic switching networks. The authors present and discuss all known tree-type space-division photonic switching networks architectures in a unified framework, and propose a number of new solutions. The discussed networks can be implemented with guided-wave-based switching elements, or laser diodes and passive splitters and combiners. The following network types are considered: conventional, simplified, and two-active stage networks. Techniques for improving SNR as well as waveguide crossover minimization are presented and discussed     

Evolution scenarios for optical telecommunication networks usingmultiwavelength transmission

The authors discuss how the transition in telecommunication networks taking place with increasing use of fiber in all segments of the networks, together with the increasing demand for broadband services, will lead to new network architectures. The customer access portion of these networks may have a large geographical range and high functionality, and may encompass switching functions. The increased use of optical routing based on wavelength multiplexing is likely to be employed in both the core and access portions of the new architectures. Among others, these developments will mean that fewer conventional crosspoint switches are required to support future broadband networks     

光移动回程小蜂窝面临的挑战及解决方案

随着移动宽带服务需求不断增加,需要运营商提供更多的无线接入网络功能。LTE和小蜂窝可提供解决无限覆盖和容量的方案。然而,回程技术在CAPEX方面昂贵,运营成本及传统的解决方案无法提供必要的结合能力和成本效率。文中定义了一个Q带点对多点的回程架构,重点介绍了在构建移动回程和无线接入网络框架中提出的萨拉班德结构,其是一种具有成本效益的网络结构,可提供多千兆能结合在Q带传输一个点对多点毫米波传输技术。此外,文中除了给出网络结构的定义外,还描述了节点的密钥类型,包括萨拉班德具体结构。     

SOME TRAFFIC ISSUES IN THE DESIGN OF VIRTUAL PRIVATE NETWORKS OVER ATM

The emergence of broadband technologies such as ATM gives rise to new developments in the domain of virtual private networks (VPNs). In this paper, a target broadband VPN (B-VPN) service is proposed, which combines the cost savings of classic VPN services and the powerful features of private corporate networks (service integration, statistical multiplexing, etc.) enlarged by the use of ATM. To reach this B-VPN service, some architectural issues related to the network supporting the B-VPN service are discussed. The traffic implications of the possible architectural choices are then examined, and from this discussion some basic principles for a VPN architecture are drawn. Finally, target VPN architectures are proposed.     

Enabling Technologies for Next-Generation Optical Packet-Switching Networks

The optical packet-switching network is considered to be one of the most promising solutions for end-to-end delivery of high-bitrate data, video, and voice signals across optical networks of the future. Optical label switching (OLS) technology incurs simpler extraction and processing of the labels so that the optical packets can be routed with low latency to the destinations. We have developed several key enabling technologies for integrated optical networks, including optical label generation, label swapping, optical buffering, clock recovery, and wavelength conversion. We have designed and experimentally demonstrated these enabling techniques that can provide efficient broadband services in future optical networks.     

B-ISDN: a technological discontinuity

The transition to B-ISDN from current networks represents a major technological discontinuity for the communications world. These discontinuities must be considered for the successful evolution of existing networks to broadband networks. The authors provide an overview of B-ISDN data transfer protocols and the services it will support. They discuss the effects of B-ISDN switching, network operations and management, signalling protocols and architectures, and networked computing     

Next-generation optical networks as a value creation platform

In this article we discuss the role of the next-generation optical networks and introduce enabling technologies that support network evolution. The role of networks is undergoing change and is becoming a platform for value creation. In addition to providing new services, networks have to accommodate steady traffic growth and guarantee profitability. We envision a next-generation optical network as the combination of an all-optical core and an adaptive shell operated by intelligent control and management software suites. Possible technological innovations are introduced in devices, transmission technologies, nodes, and networking software, which will contribute to attain a flexible and cost-effective next-generation optical network. New values will be created by the new services provided through these networks, which will change the ways we do businesses and go about our private lives.     

The fiber-optic subscriber network in Japan

Nippon Telegraph and Telephone Corporation (NTT) has two primary aims regarding the installation of optical fiber cables for subscriber networks as the access network: to provide high-speed broadband services, and to provide narrowband services through optical fiber cables with subscriber-line multiplex technology. Thus, NTT is preparing an infrastructure to support the forthcoming B-ISDN subscriber networks. NTT has been developing technologies for implementing the full-scale construction of fiber-optic subscriber networks. The present article describes the deployment methodology for these networks, their current status, and plans for their future development     

Local access optical networks

Both broadcast CATV and switched telephony access networks have evolved, over decades, to deliver their respective services efficiently. But these networks are not necessarily optimal for services that are rapidly emerging. This suggests that the access infrastructure will likely change in the future, driven by demands for new services and the costs of providing them. Will fiber optic networks play an important role? Trade-offs in desirable network properties (low initial costs, high capacity, flexible provisioning, enhanced maintenance and operations, etc.) are strongly influenced by the network architecture. We classify architectures on two characteristics: delivery mode (i.e., broadcast vs. switched) and carrier utilization (i.e., shared vs. dedicated), examining the trade-offs these imply with several examples of existing and proposed architectures. We show that optical networks can, by virtue of recent component development, be reconfigured to change their characteristics without changing the outside plant     

A vision for residential broadband services: ATM-to-the-home

The arrival of asynchronous transfer mode (ATM) networks has enabled a wide range of new interactive multimedia applications for the residential market. The article presents a vision for supporting universal residential broadband services based on an ATM-to-the-home (ATTH) network architecture. This network architecture applies to the various residential access network (RAN) architectures being deployed today, such as hybrid fiber/coax (HFC), fiber-to-the-curb (FTTC), fiber-to-the-home (FTTH), and asymmetric digital subscriber loop (ADSL) technologies. The article addresses today's residential networks and applications, to understand why a switched broadband residential network is required to support residential broadband services. After exploring residential broadband application requirements, a new class of service is proposed to support a very important class of residential broadband applications that has been not addressed. Then, the technical and strategic motivations for using the ATTH architecture are discussed in detail. A universal model for residential broadband network architecture based on ATTH is described, which is shown to apply to various RAN architectures. Finally, it discusses the signaling requirements of residential broadband services and explain why the ATM multiconnection per-call model is much more efficient than the digital stored media command and control (DSM-CC) session control protocol approach for the ATTH architecture     

走向宽带化的VSAT卫星通信

受数据音频视频广播、计算机卫星宽带交互接入和音视频会议等业务的推动,VSAT卫星通信网向宽带业务发展巳成为必然趋势。分别对应以上业务的VSAT卫星通信网也日益趋于融合成一个统一的宽带VSAT通信网。发展宽带VSAT通信网的关键技术涉及到宽带数据广播、宽带多址接入、卫星通信规程、网络综合管理和宽带虚拟子网等。     

Emerging technologies for fiber network survivability

Reducing network protection costs, while maintaining an acceptable level of survivability, has become an important challenge for network planners and engineers. This article will review technology and architectures that may be used to implement cost effective survivable fiber networks for each transport layer, and discuss the interworking system between survivability mechanisms across different layers and associated open issues. Standards development, product availability and the current status of deployment will also be reviewed. The first section reviews a class of survivable fiber network architectures that has been deployed or is scheduled to be deployed. Next is a review of emerging technologies for these survivable architecture implementations. These emerging technologies include SONET, ATM, and passive optical technology. Finally the issue of multiple layer interworking on SONET/ATM networks is discussed     

多重业务的宽带承载

多重业务的迅速发展和其拥有的多媒体、互动等新特征，使宽带网络难以有效地实现统一承载，并进而成为多重业务发展的障碍。要实现在宽带网络中可运营、可管理、可增值地承载多重业务，需要全面采用新技术。在各种新技术中，高宽带的网络技术使网络资源更丰富；服务质量（QoS）技术实现多重业务的差异化服务，从而保证业务的服务质量；强大的组播技术有效地控制和保障多媒体业务的开展；安全保障技术为多重业务提供高质量、完善的安全运营机制；高可靠性技术为宽带网络承载多重业务提供可靠、不间断地运营机制。     

Satellite ATM networks: a survey

Satellite ATM networks have significant advantages over terrestrial ATM networks. Satellites provide unique advantages such as remote coverage with rapid deployment, distance insensitivity, bandwidth on demand, immunity to terrestrial disasters, and offering broadband links. Satellite ATM networks will play an important role in the rapidly evolving information infrastructure. However, there are several obstacles which need to be overcome so that satellite ATM networks can operate in full service. The objective of this survey is to present the state of the art in satellite ATM networks and to point out open research problems. We explain the satellite ATM network architecture and cover the requirements and technical barriers for seamless integration of ATM and satellite networks. We describe the feasibility of the existing ATM cell transport methods, and deal with conventional and new satellite link access methods, and some error control schemes for the satellite environment. We then describe the problems of the proposed traffic and congestion control schemes, followed by the error performance of the Transmission Control Protocol (TCP) and Service-Specific Connection-Oriented Protocol (SSCOP) for the satellite ATM network. We present basic requirements and a possible architecture for local area-metropolitan area network (LAN-MAN) interconnection using satellite ATM and then discuss the requirements for multimedia services in satellite ATM networks     

Photonic transport networks based on optical paths

This paper explores the technologies that will enable a further leap forward in transport network evolution. First, requirements of the future transport network are elucidated. Existing network cost is evaluated and the viable means to reduce transport network cost are identified. It is demonstrated that optical path technologies such as WP (wavelength path) and VWP (virtual wavelength path) will play a key role in this. They enhance not only transmission capacity but also cross-connect node throughput cost-effectively by capitalizing on the wavelength routeing scheme. Optical path realization technologies focusing on optical path cross-connect systems are examined. Requirements for the optical path cross-connect system are then elucidated, and a new cross-connect system architecture is evaluated. The architecture exploits PLC (planar lightwave circuit) and other commercially available technologies suitable for large-scale production. The evaluations include cross-connect node upgradability, modular growth capability, total node cost, optical loss and switching power consumption. It is proved that the architecture has significant advantages over existing switch architectures. The optical path technologies provided in this paper will pave the way for a new transport network paradigm, a ubiquitous, bandwidth-abundant and affordable broadband ISDN.