ISDN: A Global Solution to Transmission Needs

The concept of the integrated services digital network (ISDN) could revolutionize information management. The purpose of the ISDN is to provide a worldwide network that offers end-to-end digital connectivity supporting a wide variety of communications services. ISDN subscribers will have direct access to a high-speed digital pipeline capable of supporting simultaneous voice, data, facsimile, and various other services and calling features.     

Basic rate ISDN workstation traffic patterns

At present, the PC class of machine equipped with a modem and connected to the public switched telephone network (PSTN) finds many applications; access to electronic mail services, access to office computers by home-workers, occasional access to a mainframe from an isolated office, etc. Two developments are coinciding which will affect this usage; PCs are being upgraded into much more sophisticated workstations, and the PSTN is to be replaced by the integrated services digital network (ISDN), a digital service offering much greater bandwidth. These developments will have a significant effect on the ways in which isolated machines are used. Some results are presented from an assessment made at University College London on the extent to which modes of usage currently prevalent on LANs might translate to the ISDN workstation. Measurements have been made of traffic on a L LAN, and extrapolations have been made to gauge the effects of interposing ISDN both on performance and on cost.     

ISDN: ADOPTION AND DIFFUSION ISSUES

Integrated services digital network (ISDN) technology has garnered a great deal of attention but not much use. Reasons for low use include decision makers' lack of familiarity with the technology and the job of cost justification. Potential adopters of ISDN can develop effective strategies for planning and infusing this technology into their organizations if they understand the implementation issues. This article examines ISDN adoption and diffusion patterns and implementation experiences of early adopters among the Business Week 1,000 companies.     

GTI,a graphical telephone interface

Graphical Telephone Interface (GTI) is a screen-based telephony application for telecommunication services. It provides an intuitive user interface to the myriad of services and features in state-of-the-art communication systems, such as ISDN or a digital (ISDN) PBX. As a high-end telephony user interface, GTI controls voice and data connections with the comfort and ease of use to today's graphical user interfaces.     

ISDN and the Internet

Current integrated services digital networks (ISDN) can provide subscribers with access to the Internet and can support variable data rate connections between Internet switching nodes. This paper describes how ISDN and the Internet can be further integrated and communication capabilities improved by expanding the role of ISDN switching centers to include certain packet switching functions. Enhancements are identified that allow narrowband ISDN (N-ISDN) to support full motion video in addition to voice and data communications. These enhancements, along with the further integration of ISDN and the Internet, would facilitate a smooth transition from N-ISDN to broadband (B-ISDN).     

ISDN中2B+D转USB网络接口设备的实现

ISDN终端产品能独立实现数字电话、传真、图文、视频等多种功能。如果将PC机虚拟成ISDN终端,就可以利用PC机丰富的软硬件资源融合ISDN终端产品的各种功能。文章分析了电信网中的ISDN2B--DU数字用户接口单元和USB协议框架,提出了一种实用的ISDN2B--DU接口转USB网络接口的实现方案,实现了NT1产品和USB主机通信,从而大大扩展了ISDN的服务领域。     

Testing Mixed-Signal Devices

Testing ISDN devices, which mix analog voice information and digital data, puts special demands on the test system. The ISDN has multiple interfaces with devices that perform a variety of functions. What was usually performed by many individual ICs is now performed by a single ISDN device. Particularly challenging are network interface and device feature tests because the test system must generate and detect the specialized frame structures in the network communication links-structures that change not only between transmit and receive but also between interfaces. Techniques to conduct these tests are described in detail. The benefits of these techniques can be increased with the use of the proper hardware and interactive, graphics-based software tools.     

Operations process planning: A systems approach

The public telephone network is evolving rapidly from an embedded analog network to a digital network with a diverse capability for new services in a multi-media environment. Planning operations processes to effectively provision and maintain this ever-changing network is a challenge. This paper presents a systems approach for operations process planning that is a cost-effective alternative to a trial-and-error method for instituting change. This methodology enables a planner to gather a full understanding of existing processes and to test out the system effects of changes to the process. An Integrated Services Digital Network (ISDN) maintenance provisioning process is used to illustrate the methodology and how it would be useful to operations planners. Extensions of the use of this methodology to architect new processes for other new services and technologies will be discussed briefly.     

平煤集团综合调度指挥系统的网络设计与实现

针对平煤集团通信专网现状 ,对其中的几种通信服务进行了比较 ,提出了基于 ISDN的网络互连方案 ,并对网络的实现作了详细介绍     

智能HLR在移动一卡多号业务中的应用

智能HLR(SmartHLR,简称SHLR)是为解决固定电话网的面向普通用户的新型增值业务(如:彩铃、一号通、号码可携带等)的业务触发和号码转换问题而提出的一种新技术。SHLR不但适用于固定电话网,而且可以引入到移动电话网内,在某些特定业务实现方案中发挥作用,包括:一卡多号(SIMN)、网间号码可携带等(NP)。本文首先介绍SHLR的作用和特点,再以一卡多号业务实现方式为例对SHLR在移动网的应用方式进行分析。     

Inter-domain service management of broadband virtual private networks

The emergence of an open market for telecommunication services provides a wide range of opportunities for the provision of value-added services by providers other than public network operators. One service already available today is a Virtual Private Network (VPN) that provides dispersed corporate sites with wide-area data communication capabilities using public network services. The introduction of Broadband ISDN allows for the provision of VPN services in a more integrated fashion. However, any effective VPN service must be able to deal with the technological and organizational heterogeneities that are present when providing a high level of service functionality over an arbitrary number of administrative and technological domains. This paper presents a management service for a VPN service that addresses some multi-domain and network heterogeneity issues. It outlines how a design based on the ITU-T's Telecommunications Management Network (TMN) Recommendation was developed and how working prototypes were implemented over real broadband networks.     

Data communications network for a merchant bank

Various problems encountered in designing a resilient data communications network to link Lazard Brothers' London, Jersey and Guernsey sites are detailed. As the network had to be capable of supporting a delay-critical (Unisys-Burroughs) poll/select environment, it was decided that the network should be based on time division multiplexers rather than statistical multiplexers, and connected to a delta configuration via high speed modems and leased analogue lines (no digital services being currently available between the UK mainland and the Channel Islands). A PC-based network management system was developed to monitor and control the network.     

用公共信道信令提升ISDN通信性能的分析

综合业务数字网(ISDN)是综合数字网的延伸,它打破了传统电话网和数据网之间的界限,扩展了网络业务的使用类型和范围。本文指出了传统的通信网的随路信令不能控制和处理ISDN多种数据业务的原因,并从ISDN用户接口部分(U-NI)和网络接口部分(NNI)的LAPD和SS7(ISUP)信令的工作原理出发,使用七号信令分析软件分析了这两种公共信道信令(共路信令)控制ISDN业务传送的过程,得出了运用这两种共路信令是支持和提升ISDN通信性能的必然趋势的结论。     

基于ISDN的局域网与INTERET连接方案的设计及分析

ISDN是当前局域网连接Internet的最佳途径之一。根据局域网的具体情况,通过选择一定的接口设备,可取得较好的连接效果。本文通过对ISDN及相关设备技术的分析介绍,给出了一个实用的网络机房连接Internet的技术方案。     

ISDN在CERNET校园网中的应用

提出了采用性能价格比极高的 2 B ISDN网络 ,作为 CERNET的第二条网络直通 Internet,该方案采用主代理机和客户机共享的网络模式 ,在不改变原有网络结构的前提下 ,仅需增加一个 UTA和一条 ISDN电话线的硬投入 ,便可实现所有网上机器流畅地在 Chinanet和 Internet上“冲浪”、收发“伊妹儿”等     

OSI implementations in Korea

Research and development on OSI became a key issue in many Korean R&D projects related to computer, telecommunications and services. The Korean computer and communications industry also finds their possible area of expansion through OSI-compatible products. But claiming OSI as the future direction in Korea at the national/government level is not near. This short paper presents various present and future R&D projects on OSI in Korea. These include ISDN, LAN, Videotex, Teletex, protocol testing, mixed mode terminal, network architecture etc.     

矿井多媒体综合业务数字网网络结构及路由协议的研究

对煤矿井工开采技术与通信线路的布置进行了深入的讨论 ,矿井多媒体综合业务数字网网络结构为光纤同轴混合接入网 ,并对其选用的资源预留协议 (RSVP)的路由算法协议进行了研究。     

福建省数字水利“一平台”总体框架研究

福建省数字水利“一平台”的提出是从顶层推进福建省水利现代化建设的必要举措。为做好省级数字水利顶层设计，考虑福建水利信息化现状及面临形势，围绕“一屏看水、一网管水”的目标，提出“6个1”的“一平台”目标建设，探索“一平台”“五统一”总体框架下的“四大体系”，分析资源共享支撑架构、三级贯通网络架构、数字赋能应用架构及其建设内容，同时结合福建省水利信息化省情，提出“一平台”需经过业务系统统一认证、关键信息集中展示，数据资源共享服务、先立后破更新迭代，三级平台分级部署、业务应用数字赋能3个阶段的实施路径，逐步实现福建省数字水利“一盘棋”建设，数字赋能省市县三级水利业务、水利政务信息化应用。