Broadband ISDN ATM layer management: operations, administration,and maintenance considerations

An overview and characteristics of the broadband integrated services digital network (ISDN) that is based on asynchronous transfer mode (ATM) is presented. ATM layer management across the user network interface (UNI) is discussed. The UNI is described, as are the ATM cell structure and its role in management protocols. There are two management protocol models which are explained; however, the focus is on the ATM layer management protocol. An overview of network management functions is provided. Some examples of ATM layer management functions based on the generic functions are provided     

ISDN PBX及X.25网关的管理

本文介绍了ＩＳＤＮ用户一网络接口的管理模型，分析了ＰＢＸ、Ｘ．２５网关的管理功能，对协议测试，管理通信进行了研究并提出模型及实现原则。     

Terminal-to-network communication in an ATM-based ISDN

This paper addresses the topic of signalling and connectionless data transfer virtual channels in ATM at the UNI. It recapitulates on the access signalling support in narrowband ISDN, as a representative of an STM network and the predecessor of the coming broadband ISDN. Also, the influence of the customer premises network architecture is taken into account. From there, it is investigated in which ways these principles can be extended, into a general access infrastructure and access configuration management for signalling and connectionless services in the ATM-based broadband ISDN. Some possible implications for the internal architecture of the CPN and the network are discussed. This brings some insight into the restrictions which standardization of these principles at the UNI may bring along for the architecture.     

Signaling System No. 7 ISDN User Part

The integrated services digital network (ISDN) user part of Signaling System No. 7 defines the signaling protocol which supports the establishment, supervision, and release of voice and nonvoice calls over circuit-switched connections between ISDN terminations of digital subscriber access lines. This paper gives an overview of the ISDN user part protocol, as defined in CCITT Recommendations Q.761-Q.766 [1], in terms of the signaling functions and procedures provided to support call and connection control in an ISDN, and in terms of the information elements and signaling messages that are used by the signaling functions in ISDN exchanges to communicate.     

ISDN in France-1987 to 1990: from the first commercial offering tonational coverage of NUMERIS

NUMERIS, the commercial integrated services digital network (ISDN) in France, is discussed. National coverage was completed in 1990. NUMERIS specifications, network components, and customer premises equipment are described. Operational experience with NUMERIS, including equipment conformance testing and ISDN implementation, is examined. Applications development and the use of partnership ventures (usually involving a user, a service provider, and France Telecom) are discussed     

实用化ISDN（2B＋D）第一类用户／网络终端设备（NT1）简介

本文从特性、功能、实现、结构和使用等方面简要介绍了实用化ＩＳＤＮ（２Ｂ＋Ｄ）第一类用户／网络终端设备（ＮＴ１），有助于增进对该设备在ＩＳＤＮ网中运用的了解。     

Object-oriented design of ISDN call-processing software

The development of object-oriented programming (OOP) software for a prototype switching system, including the DSS1 protocol on integrated services digital network (ISDN) subscriber signaling and the ISDN user part (ISUP) for network signaling, is discussed. The major goal of the project is to determine whether switching system software can be clearly structured by using the rules of OOP, and whether the use of OOP concepts leads to an improvement in productivity and quality for large software systems. The standard classes, application classes, class hierarchy, and layer model with the OOP project are described. The experiences in applying OOP for the development of switching system software are summarized     

宽带接入网的体系结构

讨论了宽带接入网的进展 ,论述了宽带接入网及其用户 -网络接口 (U NI)、业务节点接口 (SNI)和电信网管理(Q3)接口 ,并总结了宽带接入网的主要功能以及宽带业务节点接口 (VB5 )标准的主要原则。还例举了多媒体接入体系的实例及其最新发展。     

International standards for the broadband ISDN user-network interface

Recently, a series of international standards on broadband ISDN were approved in CCITT Study Group XVIII. These standards establish fundamental details on transmission, multiplexing and switching for broadband aspects of ISDN. This article reports on the current definition of the BISDN user-network interface. The UNI reference configuration, physical medium, rates, structure, ATM functions, and operations and maintenance functions are addressed with consideration given to open issues and the direction of future standards activities. Objectives for the UNI capabilities have generally been met with the current CCITT specifications. Some of the UNI physical layer ‘options’, however, potentially impose networking cost penalties.     

Omissions and ambiguities in CCITT Recommendation Q.921

The data link layer protocol for the integrated services digital network (ISDN) user/network interface, known as link access protocol-D (LAPD), is a protocol that operates at layer 2 of the open systems interconnection (OSI) architecture. Its purpose is to safely convey information between layer 3 entities using the D-channel. The information types that LAPD is intended to transport include call control signaling, packet mode communications, and management information. Observations are made in this article about what are, in the authors' opinion, the most confusing points of CCITT Recommendation Q.921 with comments related to data link layer address field, broadcast connections, terminal endpoint identifier (TEI) management procedures, layer 2 frames exchange, and connection management entity response to MDL-error indication primitives. This article intends solely to clarify the recommendations so that their concepts and procedures become easier to understand and implement, which can lead to significant saving of time for those who must eventually use LAPD procedures or develop the software for handling them     

ISDN signal distribution network

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     

An object-oriented analysis of a BISDN control system with a focus on the UNI protocol object

The control system of a BISDN network will undoubtedly be very complex to design, implement and maintain. Its complexity has led researchers to look for ways of breaking down the problem into smaller and manageable parts. This has motivated the use of an object-oriented approach to analyse and comprehend the BISDN control system. This paper thus presents an object-oriented analysis (OOA) of a BISDN control system. This analysis is based on a method introduced by Coad and Yourdon and comprises five steps. All five steps, namely identifying subjects, identifying objects, identifying structures, defining attributes, and defining operations, will be worked out in detail with an emphasis on the user network interface (UNI) signalling protocol object. Four subjects, nine objects, and three structures are identified in the problem space at hand. This structuring offers a framework to analyse in detail the three aspects, data, structure and dynamic behaviour, of the UNI signalling protocol. A parallel between this approach and the well known approach used by the International Telecommunication Union (ITU) for specifying signalling protocols and contained in Recommendation I.130 is drawn. The Coad and Yourdon OOA approach applied to a BISDN control system can be used for the analysis of different aspects of such systems. This paper focuses on the UNI signalling protocol object which leads to a complete specification. Any protocol resulting from such analysis can be claimed to be object-oriented protocol. This approach offers modularity and thus offers a way of structuring the problem space into identifiable objects and data. Full benefits of object orientation can be gained only in the consistent use of object orientation throughout all steps in the development process. The proposed approach allows one to create libraries of generic procedures which can be reused in specific implementations.     

Progress Towards User Access Arrangements in Integrated Services Digital Networks

This paper deals with arrangements for local access to emerging Integrated Services Digital Networks (ISDN's). The ISDN concept is here introduced as the focal point for the ongoing international activity on multiservice digital networks. ISDN's are conceived as networks which have evolved from the basic digital telephone networks and they will provide end-to-end digital connectivity to support a wide range of services including voice, data, sound, and video applications. After giving a general outline of the evoving ISDN network scenarios for digital communications, the paper reviews the international trends on user access arrangements in terms of 1) user equipment and interface configurations, 2) access channel structures and information transfer capabilities, 3) local distribution plant configurations (with emphasis on the copper plant), and 4) access protocols.     

A signaling architecture for wireless ATM access networks

A multiservice wireless Asynchronous Transfer Mode (ATM) access system is considered from a signaling protocol viewpoint. In an attempt to generalize and extend results and experiences obtained from the specification, design, and implementation of fixed ATM‐based access networks, we extend the concept of the broadband V interface (referred to as VB) for application to wireless ATM access networks. The proposed architecture follows the signaling structure of Broadband ISDN (B‐ISDN) User–Network Interface (UNI), thus offering the possibility for integration of the wireless ATM access system into fixed B‐ISDN. It is shown that the use of the proposed access signaling architecture provides cost effective implementations without degrading the agreed Quality of Service (QoS), and simplifies call/connection and handover control. The evaluation of the proposed access signaling protocol structure yields results that fall within acceptable ATM signaling performance measures. A performance comparison of our approach with an alternative access signaling configuration is also carried out to quantify the relative gains. This revised version was published online in August 2006 with corrections to the Cover Date.     

IMS与传统PSTN网络的互通问题研究

目前,下一代网络（NGN）的核心技术正从传统软交换向IP多媒体子系统（IMS）衍化。在IMS这个全新的网络构架下,如何实现与传统公用交换电话网（PSTN）的互通成为目前网络转化过程中急需解决的问题之一。从阐述IMS网络的系统架构入手,通过典型的呼叫实例分析,探讨从IMS终端到PSTN终端的呼叫流程。着重分析互通过程中各IMS网络功能实体的详细作用,以及会话发起协议（SIP）与综合业务数字网用户部分（ISUP）之间的转换映射关系。     

Current role and future evolution of the ISDN Signaling system inNTT's network

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     

ATMUNI信令的功能划分

ＡＴＭ用户－网络接口（ＵＮＩ）信令采用ＯＳＩ的分层结构,本文首先简要介绍了ＡＴＭＵＮＩ信令协议的体系结构以及各层的功能。然后详细描述了ＵＮＩ信令功能模块的划分,以及各模块的功能。     

Common channel signaling for international service applications

The message transfer, telephone user, and integrated services digital network (ISDN) user parts of CCITT Signaling System No.7 (SS7) are described. The introduction of SS7 to provide control of international circuits is described. The intent is to provide a perspective on the advantages of using common channel signaling for ISDN     

Signaling System No.7: a tutorial

A tutorial overview of the salient features of SS7 is provided. Its history is briefly reviewed, and the SS7 network services part (NSP), which corresponds to the first three layers of the Open Systems Interconnection (OSI) Reference Model, is described. Signaling network structures that, in conjunction with the NSP, provide integrated services digital network (ISDN) nodes with a highly reliable and efficient means of exchanging signaling messages are discussed. The nodal capabilities of connection (call) control and remote process invocation and management and other functions of the user parts of SS7 are examined. The very stringent performance requirements of signaling systems, which reflect the critical nature of signaling functions and their real-time exigencies, are stressed. A broad outline of the likely evolution of ISDN signaling systems in the remaining years of this century is sketched