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1.
This paper presents an outline of the key network standards issues addressed in CCITT as a necessary part of the development and implementation of ISDN. The results achieved in the 1981-1984 Study Period focused on ISDN network functional requirements, ISDN numbering plan, connection types to link ISDN interfaces across the network, and the relationship of the ISDN protocol model with the seven-layer ISO model. The additional network issues which must be resolved in the current (1985-1988) Study Period are identified and briefly discussed. Of particular interest are internetworking between ISDN and existing networks, numbering plan interworking, routing, and maintenance standards. The market success of ISDN depends upon early resolution of these network standards to meet the field trials scheduled for 1986-1988 and the first implementations expected in 1988-1990. 相似文献
2.
《Communications Magazine, IEEE》1990,28(7):78-83
The current role of the integrated services digital network (ISDN) Signaling System is examined, covering general features of the ISDN protocol, functionalities supporting ISDN services, and functionalities supporting existing services. The Signaling System No.7 (SS7) network and its operation are described. The future evolution of the ISDN signaling system is discussed 相似文献
3.
Multi-rate ISDN 总被引:1,自引:0,他引:1
Multi-rate integrated services digital network (ISDN) is a new technology for providing dialed-up, circuit-switched, isochronous communications for bandwidths from 128 kb/s to 1.536 Mb/s (DS-1) or 1.920 Mb/s (CEPT-1). Multi-rate ISDN provides a simple way to extend ISDN network services to match the higher bandwidth requirements emerging for videoconferencing, multimedia, imaging, and other high-speed applications. Using this technology, network service providers can offer high-speed connectivity within the boundaries and benefits of existing, circuit-switched, central office and transmission equipment. Only minor changes are required in the operations administration and maintenance and provisioning (OAM&P) procedures associated with multi-rate ISDN, versus existing ISDN transmission and central office maintenance procedures 相似文献
4.
The integrated services digital network (ISDN) offers on-demand switched end-to-end digital connectivity over the wide area, enabling the integration of both voice and data services over a common core network. This paper considers the role of ISDN in data networking, both as the core transport network and as a means of enhancing resilience in a mixed-technology data solution, complementing other data network technologies. The issues associated with data transport based on an ISDN solution are considered, and include security, bandwidth utilisation, scalability and the management of ISDN-attached devices. Optimising the use of ISDN networks for supporting the most prevalent routed and routeing protocols is also discussed. 相似文献
5.
《IEE Review》1990,36(9):357-360
The integrated services digital network (ISDN) standard was defined in 1972 yet the progress towards its implementation has been very slow and very little is yet on offer to the consumer. The author looks at the vision where the concept of ISDN transforms the telephone network into a transport mechanism for all communications needs. Services offered by ISDN are discussed as are implementation and tariffs 相似文献
6.
The evolution from analog to integrated services digital network (ISDN) telecommunication services at Tenneco Gas and the features of its telephone system are described. The results of implementing ISDN in data operations are examined. The benefits of ISDN for Tenneco are briefly summarized 相似文献
7.
US Bank's experience with a number of applications supported by Northern Telecom's DMS-100 integrated services digital network (ISDN) is discussed. Some of the applications that US Bank has been using, as well as some applications planned for near-term implementation, are described. The current applications supported by ISDN are the centrex telephone; message desk call receptionists; systems network architecture (SNA) host access; automatic teller machines; point-of-sale network; and wide-area networking. Future ISDN applications include support of loan approvals and service kiosks 相似文献
8.
Rana A.H. Briancon A.C. Check W.A. Ortiz C. 《Selected Areas in Communications, IEEE Journal on》1992,10(6):1081-1093
The authors discuss the applications of very small aperture terminals (VSATs) to the ISDN. Typical VSAT network architectures include point-to-point interactive, point-to-multipoint broadcast, and interactive star configurations. VSATs and satellite communications have found new applications for integrated network solutions yielding hybrid network architectures that mix terrestrial and satellite segments. These issues and their implications are examined in the context of ISDN. Six hybrid network configurations are described to address various applications. A proof of concept implementation utilizing a hybrid terrestrial/satellite ISDN network was performed. The demonstration showed the feasibility of using hybrid networks as a backup for terrestrial communications as well as for service extension via satellite. The architecture and implementation of this configuration are described 相似文献
9.
Kano S. Kitami K. Kawarasaki M. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1991,79(2):118-124
The history and achievements of ISDN (integrated services digital network) standardization in the CCITT are reviewed. Two of the most important developments, ISDN basic and supplementary services and broadband ISDN, are focused upon. The underlying concepts in the discussions of ISDN standardization are briefly explained 相似文献
10.
The advantages offered by the integrated services digital network (ISDN) to US Department of Defense (DoD) communications in terms of interoperability provides a framework for a discussion of ISDN standards. The standards organizations working on ISDN and network protocol standards are described, and their relationship to each other is delineated. The status of the standards being developed is discussed, and those that would be of special interest to the US DoD are examined 相似文献
11.
12.
交换机选择路由功能的实现在一定程度上决定了ISDN的网络结构,因此,在组织ISDN网络时,应考虑交换机选择路由的能力。 相似文献
13.
Nakano S. Nagai N. Sawada R. Miyagishi O. 《Selected Areas in Communications, IEEE Journal on》1990,8(3):360-367
A human-machine interface has been created for an integrated services digital network (ISDN) network control unit (I-NUU). I-NUI is a sophisticated terminal device that allows a voice communication channel and two data channels to be connected through an ISDN I-series interface. ISDN communication functions and network control operations were analyzed to determine the required characteristics of I-NCU. I-NCU features the minimum number of control buttons and a liquid crystal display. Visual and audible information are used to keep the operator fully informed about the state of the communication channels 相似文献
14.
本文介绍了我国对综合数字网(ISDN)的需求和目前我国实施ISDN的网络装备基础;描述了我国ISDN的实施方案以及ISDN的业务应用。 相似文献
15.
The shortcomings of the existing asymmetric digital subscriber line (ADSL) standard ANSI T1.413 for application with the integrated services digital network (ISDN) are explained. An ADSL system modified by increasing the high-pass cutoff frequency of the splitter to about 140 kHz and, therefore, moving also the pilots, has been simulated under noise conditions and the ISDN requirements of the German subscriber line network. The reach reduction due to ISDN compared with the “plain old telephone service” (POTS) application is shown to he between 10% and 15%. It is proposed to apply ISDN ADSL rather than POTS ADSL 相似文献
16.
Early projected benefits of the integrated services digital network (ISDN) are evaluated from a customer premises equipment (CPE) perspective. It is argued that economic conditions continue to affect ISDN investment in the USA. Worldwide customer acceptance of ISDN is contrasted with earlier projections and shown to be running at about 25% of earlier projections. IBM's current ISDN product set is discussed briefly. Even though the rollout of services has not yet achieved expectations, IBM believes the potential for ISDN use by customers is significant 相似文献
17.
During the past decade, the opportunity has arisen to economically combine data and voice services onto a single system, the integrated services digital network (ISDN). Studies in CCITT have led to the production of a set of Recommendations covering aspects of the ISDN, including the customer terminal interface. Inevitably, there are significant differences between the customer terminal interfaces recommended for dedicated data networks and that proposed for the ISDN. To ensure a smooth transition towards the introduction of ISDN based services, the CCITT have published recommendations describing how existing terminal interface designs may be connected to an ISDN. These recommendations are the subject of this paper. 相似文献
18.
ISDN protocols for connection control 总被引:1,自引:0,他引:1
The technical details of the integrated services digital network (ISDN) access protocols for connection control are described. These protocols are the ISDN physical layer, link layer, and layer 3, which are documented in International Telegraph and Telephone Consultative Committee (CCITT) Recommendations I.430, I.441, and I.451, respectively. Other work that supports or enhances these protocols is described. In particular, the ISDN protocol reference model, how it relates to the open systems interconnection reference model, and CCITT Recommendation Q.932 on service feature control on ISDN are discussed. Possible uses of ISDN, possible evolution paths, and some understanding issues related to ISDN are also described 相似文献
19.
Niznik C. Chatterjee A. Walter D. 《Selected Areas in Communications, IEEE Journal on》1986,4(8):1230-1240
The Integrated Services Digital Network (ISDN) provides basic architecture for existing, as well as future residential plus business communications. ISDN overlayed with CCS#7 of a digital PSTN (Public Switched Telephone Network) can be the ultimate, ubiquitous network for circuit switch (voice, data), packet switch (voice, data), and private line (voice, data) applications. Assuming that the present ISDN has to interwork in the present physically separate overlayed networks (voice and data), significant problems are expected to emerge for designing hardware and linking softwares for handling packet traffic. In this paper, the software-related problems, when ISDN packet distribution nodes have to handle an ISDN interface, will be outlined with an ISDN software protocol solution. An approximation of the delay involved in the telephone switching system which is part of ISDN processing as well as the delay for the interface gateways, the HOST computer nodes, and the LAN and WAN computer nodes will be identified and formulated to reflect the total performance measure defined. Major emphasis is given to flow and congestion control performance measures in the ISDN Gateways, which are analyzed and simulated with the assistance of the basic delay table transfer software model developed for the IMPS and gateways in the ARPANET, MILNET, and MINET. The performance evaluation of this basic ISDN interfacing software, which only involved one ISDN level, i.e., the HOST or gateway and its related subnetworks, is simulated on sections of these networks to illustrate its congestion control effectiveness. There are six mathematical software techniques to account for end-to-end delay, which form the basis for the solution to these ISDN software-hardware problems in the Interface Gateways connecting the electronic switch to the computer network components. 相似文献
20.
The author discusses the ISDN Staged Transport System (STS). The STS illustrates how an ISDN network can be used as a flexible distribution medium for directing real-time signals over a WAN to a staged transport server. Although the signal feeds distributed by the STS application are audio voice grade circuits (VGCs), the architecture lends itself to other signal types, such as video. Moreover, ISDN bridges and routers allow the real-time communications infrastructure to distribute bulk recorded signals as well. Finally, the multimedia wide-area connectivity provided by ISDN allows an entire signal processing operation to be remoted, with receivers, storage, and mission control all managed from a single site (or multiple sites) on the network. While the STS application uses the user to user information element (UU-IE) to control signal processing on the edge of the ISDN network, the UU-IE could just as easily be used on the interior of the network by switch adjuncts to augment dialed number routing with intelligent-application-based routing. When combined with the rich set of commercially available applications available on many ISDN switches and adjuncts, sophisticated signal processing, distribution, and management networks could be rapidly configured and deployed with relative ease 相似文献