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.     

Interactive Broad-Band Dialogue Systems in the Integrated Services Digital Network (ISDN)

In the integrated services digital network of the future, Which will also have broad-band capacity, it will be possible to offer information services with multimedia presentation (e.g., with support of audiovisual material). For easy use, dialogue structures must be developed which lower the barrier of access for casual users. Offering information in a variety of applications at any place, a technical system consisting of different types of storage devices, operating Systems, and terminals, connected by a narrow- and broad-band switching and transmission system, must be available.     

Present Trends in High-Speed and Broad-Band Communications Services in Japan

This paper describes present trends in high-speed and broad-band communications services in Japan. It gives an overview of video, high-speed digital leased circuit and satellite digital communications services, and gives examples of their applications. Recent trends in telecommunication services and technology are described, including video conferencing services presently available in more than ten cities throughout Japan, as well as a video response system which is about to be put into service. It also describes the present status of Japan's cable television (CATV) system and discusses its future development. Finally, NTT's plans for high-speed and broad-band communications service in the future are previewed.     

Broad-Band Media for Urban Communications

The characteristics of media for future broad-band two-way urban communications are reviewed. The media discussed include existing paired telephone cables, modified paired cables for higher frequency use, coaxial cable, waveguide, optical fibers and microwave radio. The paper discusses basic physical and transmission properties as they relate to broad-band use in the urban environment. Emphasis is placed on the portion of the plant between the customer and the nearest central location such as a telephone central office building, because this portion of the plant is controlling both physically and economically. The paper includes a discussion of the relevant characteristics of the urban environment, since these will have a strong impact on the suitability of the various media.     

Broad-Band Interactive Communication Services to the Home: Part II--Impasse

Four years have passed since the survey was conducted leading to the preceding paper [1]. Little work has been done, and even less progress has been made toward the goal of the new system developments. The present paper explores impediments that the writer believes are presently blocking the development of the potential broad-band cable interactive services industry. The key issues present are identified and a statement of the missing elements is provided. The paper concludes that broad-band cable information services to the home can be turned into reality even as early as the late 1970's or the mid 1980's. The writer suggests that governmental intervention may be required, primarily in standard's development, since present developments appear to be proceeding along dead-end trajectories. And, unless corrective action is taken we could easily inadvertently delay by many years the date when two-way services are able to pay their own way and thus be economically viable. Doing without also has its price. Society pays a high, although intangible, penalty in not having early access to a highly social, useful system until a much later date than technology and long-range economics would dictate.     

自动交换光网络业务

文章介绍了ASON网络的业务类型、业务等级、接入方法等属性，给出了几种业务模型实例及应用，并对ASON管理平面对业务的管理进行了讨论。     

Integrated Circuits for Broad-Band Communications Systems

Integrated circuits for broad-band communication systems which enable broad-band communication between subscribers require LSI's with a performance concerning speed, complexity, and power dissipation which cannot be fully met by present semiconductor technologies. The requirements for coders and decoders, line transmission circuits, and broad-band switching network elements depend upon the system concept chosen. For one chosen system concept, these requirements are derived. By using a representative model for the development of the demand, characteristic curves for the demand of subscriber-line circuits and for central unit elements are resulting. From these curves the optimum semiconductor technologies, complexities, and design strategies are derived. It can be assumed that the results are rather independent of variations of system concept and introduction models.     

Architecture of Broad-Band Communications Systems

At present there are worldwide efforts directed towards a services-integrated broad-band network. The first section of this paper describes different solutions of broad-band network components such as subscriber premises networks, local loops, subscriber exchanges, and trunk networks. The design of these components was taken from various proposals and broad-band communication field trials carried out in several countries up to 1984. In the second section, we consider the possibilities and implications of integrated optical components and of optical coherent communication techniques for broad-band networks in the far future.     

A Broad-Band Amplifier Output Network Design

An analytic design method for a lossy gain-compensating network is presented and the advantages of lossy networks are discussed. Examples of two-stage amplifiers using FET's and bipolar transistors are presented to show the feasibility of this particular network in low power amplifier designs. These amplifiers obtain gains of 15.4+-0.5 dB with a 2.5-dB maximum noise figure in the 4.0--6.0-GHz frequency range and 16.5+-1.2 dB with a maximum input VSWR of 1.78:1 over the 1.0--2.0-GHz frequency range, respectively.     

Broad-Band Interactive Communication Services to the Home: Part I--Potential Market Demand

This paper describes a questionnaire-type survey conducted in 1970 of the nature, size, and composition of the likely market for broad-band two-way services to the home. Market demand characteristics are considered in detail for thirty likely services. The composite magnitude of the industry is estimated as essentially starting in 1980 and building up to a dollar volume of $20 billion per year.     

大城市双向CATV网交互业务的实现

提出了在大城市双向 CATV网上实现交互业务的分级系统结构 ,包括小区中心站的组成模块、功能以及双向机顶盒的结构。提出了大型 CATV网上实现 VOD的实用解决方案 ,通过多种 VOD方式 (TVOD、NVOD、INVOD、ANVOD )动态组合实现高质量的 VOD业务。探讨了交互业务如何在系统各级上合理分配。     

The Modeling and Simulation of a Circuit Switched Distributed Interactive Terminal Network

The newly installed terminal switching network at Sandia National Laboratories has been modeled with analytic and simulation techniques. Using classical queuing techniques and parameters derived from recorded usage data, fair and equitable allocations of interactive computer ports have been made. The allocations were then refined through the use of simulation techniques. The effect of balking as an alternative to entering queues has been shown to have substantial performance and stabilization effects on the network. In addition, it was found that the probability of balking as a function of queue length is not a monotonically increasing function. The simulation programs are also used to evaluate the performance of other interactive computer systems when subjected to various loads.     

宽带互动电视业务的网络建设探讨

在三网融合背景下,结合广州有线电视网络状况,深入分析了互动电视用户行为习惯,提取关键数据,按照滚动投资、逐步建设和合理拓展原则,对宽带互动电视业务的网络建设方案展开探讨。     

Switched Communications for the Department of Defense

The Department of Defense, in response to its unique telecommunications needs and in an effort to take advantage of advances in technology, has embarked on an evolutionary, systematized program to develop and procure electronic, software controlled circuit switches. Two development programs presently underway will result in the fielding of two kinds of state-of-the-art circuit switches; a large hybrid circuit switch which will accommodate the existing analog telecommunication environment and provide the means to evolve into the digital world of the future, and a pair of smaller digital circuit switches which, while providing limited accommodation of analog equipment, are primarily intended for the later stages of the digital evolution. The characteristics and capabilities of the circuit switches are described in terms of both architecture and implementation.     

Services Integration and Multiplexing for Broad-Band Communication Systems

In broad-band communication networks, a number of services are simultaneously available to the subscriber. The issues of service integration and multiplexing techniques, and their impact on network topologies, are addressed in this paper. Alternative realizations of broadband networks, together with necessary electrical and optical components, are discussed. A comparison between the different alternatives is also made.     

Design of a New Broad-Band Isolator

The design theory and experimental results of a proposed broad-band technique of an isolator are presented. The isolator not only has a broad-band backward loss but also a low broad-band insertion loss. The network constants and the performance are obtained in connection with the magnetic loss of ferrite, and they are confirmed by experimental data. The trial ultrawide-band isolator the performance of 20-dB isolation over the frequency band from 70 MHz to 800 MHz.     

Role of Satellites in Broad-Band Interactive Cable Networks

The possible role of satellites in broad-band interactive communications networks is described primarily in terms of a long distance transmission facility interconnecting several such networks over a wide geographical area. Discussion of the interface between the cable and satellite facilities is presented as well as a review of current broad-band operational and experimental uses of satellites which might be applicable to future system design.     

电子虚拟实验室系统网络通信的设计

文章提出了根据电子虚拟实验室系统的功能要求进行架构的方案,利用三层C/S模式实现系统总体框架的搭建。在该架构模式下根据Winsock的通信机制,利用VC++的MFC_CSocket类实现服务器与客户端的网络通信连接,同时实现系统中所要求的在线答疑功能的设计。经测试,这种网络通信的设计较成熟稳定,能够实现设计目标。     

Design of Middleware for Interactive Data Services in the Terrestrial DMB

In this letter, we introduce a new middleware architecture and its generic application programming interface (API) (called the T‐DMB MATE API) for terrestrial digital multimedia broadcasting (T‐DMB). Middleware in T‐DMB enables inter‐operable applications to be downloaded from both broadcast and telecommunication networks in advance and to be executed in any type of T‐DMB receiver. The middleware we introduce here is especially designed to support a proposed method for application provisions applied to a concept of application module appropriate to the service environment of T‐DMB. We also verify the designed T‐DMB MATE API through the implementation of the middleware and its application in a PC‐based receiver.