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1.
A nodal system architecture developed by Nippon Telegraph and Telephone (NTT) that will allow stepwise evolution to broadband integrated services digital network (B-ISDN), starting from the current nationwide narrowband integrated services digital network (N-ISDN) system in Japan, is discussed. The status of the current N-ISDN and the requirements for B-ISDN as the next step after N-ISDN are discussed, followed by a scenario for the evolution of B-ISDN from N-ISDN. A plan is outlined for the first ATM switching service for high-speed data transfer and a nodal system architecture permitting easy evolution to full B-ISDN  相似文献   

2.
A set of asynchronous transfer mode (ATM) bearer service categories, differentiated in terms of quality of service (QOS), that will support the large spectrum of applications expected in broadband integrated services digital networks (B-ISDN) is defined. The evolution of applications and the traffic requirements in B-ISDN/ATM networks are described, and the evolution of network services to address these requirements is discussed. The definition of ATM bearer service categories necessary for the economical support of initial applications and evolution to future B-ISDN services is proposed. The elements of the ATM traffic management strategy to support these service categories are presented  相似文献   

3.
The key features of the synchronous optical network (SONET) and asynchronous transfer mode (ATM) standards for the broadband integrated services digital network (B-ISDN) public network, which is expected to provide a powerful and ubiquitous infrastructure to support the emerging gigabit-per-second data and multimedia applications, are reviewed. The advantages of ATM, the ATM cell format, the B-ISDN protocol reference model and the ATM layer, the ATM adaptation layer, and ATM traffic management and signaling are discussed. An experimental high-performance parallel interface (HIPPI)-ATM-SONET interface is presented as an example to illustrate how the SONET and ATM techniques can be used to provide end-to-end transport for applications requiring a bandwidth of 800 Mb/s and possibly 1600 Mb/s  相似文献   

4.
The next generation personal communication network will likely internetwork wireless networks via the ATM/B-ISDN to enable ubiquitous broadband personal communication services. Support of user terminal mobility, particularly the capability for fast and seamless handoffs, over the ATM/B-ISDN is an expected requirement that is not currently met. We propose extensions to the ATM/B-ISDN user transport and signaling network architectures and signaling protocols to meet these requirements. The new architecture employs the Mobile Virtual Circuit (MVC), a dynamic connection tree in which routes are predetermined but not set up for potential handoff connections. During a handoff, associated signaling using source-routing with a new robust adaptation feature is employed for fast resource allocation to establish the handoff connection by distributed control. We also address the new problem of packet ordering synchronization to enable a seamless handoff. The connection tree reconfigures after each handoff to enable continuous support of successive handoffs. The proposed scheme optimizes handoff delay over the ATM/B-ISDN while minimizing unnecessary resource allocation, chances of handoff failure, and call processing load in the intelligent network, and the extensions are backward compatible to current ATM/B-ISDN standards and implementations.This paper was presented in part in PIMRC'95 in Toronto, and Globecom'95 in Singapore. This work was supported by the Canadian Institute of Telecommunications Research (CITR), funded under the Canadian Federal Government's Networks of Centres of Excellence Program.  相似文献   

5.
Chen  T.M. Liu  S.S. 《IEEE network》1994,8(4):27-40
As research has progressed, it has become clear that the main difficulties in ATM pertain to its operational details rather than the concept. And it seems likely that these control issues will be much more complicated and costly for ATM switches when compared with current telephone circuit switches. The asynchronous transfer mode (ATM) is the target switching technique for the future public broadband integrated services digital network (B-ISDN). The purpose of this article is to examine the management and control functions in ATM switching systems implied by current industry standards and agreements on OAM and traffic control. Until now, ATM research in the areas of switch design and traffic control have progressed essentially independently. First, we briefly review the B-ISDN Protocol Reference Model and its representation of the different information flows in ATM. Network management and traffic control principles in ATM, and in particular OAM, are overviewed. With this information as background, we attempt to infer their implications on the functional blocks of an ATM switching system. An example switch architecture model with distributed management and control functions is outlined, and some design issues are discussed  相似文献   

6.
Satellite ATM for broadband ISDN   总被引:1,自引:0,他引:1  
This paper presents the development of satellite ATM for broadband ISDN based on the Research in Advanced Communications in Europe (RACE) CATALYST project. The purpose of the project is to develop an experimental ATM satellite link for the future B-ISDN services, particularly for the interconnections of the ATM testbeds which are in the form of broadband islands developed in Europe. Then initial ATM based B-ISDN can be introduced by interconnections of these broadband islands. An evolutionary approach has been adopted in the development of the ATM networks that the CATALYST project has developed the equipment to be able to interconnect the newly developed ATM testbeds as well as the existing networks such as DQDB, FDDI and Ethernet networks. In March 1994, the project carried out an experiment on the second demonstratoras the Laboratories of Alcatel Telespace in Nanteere near Paris to demonstrate the capability of the satellite ATM connections supporting data, voice, video and multimedia applications. This experiment provided a real system demonstration of satellite ATM for B-ISDN. In the light of the experiment, this paper presents the model and architecture of the ATM satellite equipment, studies the relevant issues and the impact of ATM-via-satellite on the applications and the protocols, and evaluates of satellite ATM based on some measured and simulated results.  相似文献   

7.
指出了ATM网络存在的安全威胁,讨论了ATM网络的数据加密技术、完整性服务等ATM网络安全技术。在基于将ATM的安全层置于AAL层和ATM层之间的观点上,本论文设计了一个数字签名结构和密钥交换协议,该协议作为呼叫建立过程的一部分,嵌于现存的ATM信今协议中。这些安全技术可透明地加入到B—ISDN的协议参考模型中,无需改变现存的协议标准。  相似文献   

8.
This article surveys the restoration architectures for asynchronous transfer mode (ATM) network survivability that have been actively studied in this decade. Network reliability is critical for recent and future networks that will advance the information era. Moreover, it is one of the biggest factors in designing and managing networks. Since the early telecom network era, many restoration systems have been developed for plesiochronous digital hierarchy (PDH), synchronous digital hierarchy (SDH), synchronous optical network (SONET), leased lines and so on; and they were surveyed in many papers and books. This article focuses on new restoration techniques for ATM networks. First, the requirement studies are introduced. This includes the scant results published on the influence of failure and the state of failure analysis. Next, restoration schemes are categorized and briefly introduced. Examples include centralized control, automatic protection switch (APS), self-healing ring (SHR), self-healing network (SHN) and failure resistant virtual path (FRVP). In order to achieve adequate restoration probability with minimum cost, a network design scheme is necessary; thus, network design issues are introduced. Finally, this article focuses on the issues, future work, and problems that remain to be solved.  相似文献   

9.
The broadband ISDN (B-ISDN) is being tailored to become the universal (standardised) future netowrk, and will be capable of supporting a wide range of multimedia, multi-party applications. It is based upon the same principles as its narrowband predecessor and hence can be regarded as a natural extension of it. However, the move away from constant bit rate circuit switching towards the use of asynchronous transfer mode (ATM) technology has provided much needed flexibility, especially in terms of the connection bandwidths and quality of service available to the user.This paper briefly describes the network capabilities that B-ISDN should support and how they have been derived from a representative sample of user applications principally proposed by ITU-T/ETSI and Digital Audio-Visual Council (DAVIC). The identification of the required network capabilities is the first step towards the specification of signalling protocols for the B-ISDN which must be flexible enough to support the wide range of current and future advanced applications and services. One such potential future B-ISDN application, which demonstrates the range of signalling functionality required, is the 'Travel Agent Service' which is treated in detail.  相似文献   

10.
The development of the broadband integrated-services digital network (B-ISDN) is part of the continuing evolution of the telecommunications network. The author considers the expected rate of increase in information-carrying capacity to the general public and its needs for interfacing and service. He proposes a technique of shaping/policing the channel capacity which will be easily understood by both user and network provider. Finally the uncertainties that remain in the way that applications may exploit the ATM network and the consequent different needs for signalling and control have been highlighted  相似文献   

11.
The authors discuss the architecture and protocol for broadband ISDN (B-ISDN) based on the CCITT standards. The discussion attempts to address the general concept of B-ISDN architecture and protocol and, whenever possible, present alternatives and the rationale for decisions in the selection of the protocol. B-ISDN is presented as a network evolution, and the impact of the asynchronous transfer mode (ATM) on the network is described. The role of virtual channel and virtual path in B-ISDN is discussed. The B-ISDN protocol structure and lower layer functions comprising the physical, ATM, and adaptation layers are presented, and the tentative trends of signaling and traffic control for the B-ISDN are delineated  相似文献   

12.
郑云章 《数字通信》1996,23(3):7-10,50
本文首先通过对宽带业务发展情况,ATM标准,ATM适配层的分析引出了ATM对B-ISDN发展的作用及向B-ISDN过渡的步骤,并指出工发具SMDS和FR业务接口的ATM交换机,对实现N-ISDN向B-ISDN过渡具有积极现实意义,其次介绍和分析了ITU-T,日本NTT及欧洲各国关于ATM和B-ISDN的标准化活动,应用试验等情况。  相似文献   

13.
The introduction of wireless ATM (WATM) in customer premises network environments necessitates the design of mobility protocols, since the existing versions of B-ISDN signaling do not support terminal mobility. Such protocols can be deployed either as extensions to the standard signaling capabilities, or as individual solutions that have little or no impact on existing infrastructures (switches, signaling software, etc.). A WATM architecture that adopts the latter approach is presented. After a discussion of the problems encountered in the integration of wireless networking and B-ISDN ATM technologies, a mobility management and control (MMC) protocol is proposed. Finally, in the framework of the proposed MMC protocol, algorithms for implementing mobility procedures (handover and registration) are described  相似文献   

14.
The ATM layer chip: an ASIC for B-ISDN applications   总被引:1,自引:0,他引:1  
The authors describe the architecture of an experimental research prototype application specific integrated circuit (ASIC) designed to serve as a generic building block of the future broadband integrated services digital network (B-ISDN). The chip performs common asynchronous transfer mode (ATM) layer functions such as cell assembly and cell disassembly. A new media access control (MAC) protocol developed for a broadband customer premises network is also integrated in the chip. The chip interfaces to the B-ISDN through a synchronous optical network (SONET) synchronous transmission signal-3c (STS-3c) framer chip. The ATM layer chip has been designed using 1.2 μm CMOS technology with a die area of 5.4×5.4 mm2 and approximately 27000 transistors. Experimental results are described. At the user network interface, the chip can be used to implement broadband terminal adaptors and the network termination. At the broadband local exchange, the chip can be used in the implementation of ATM statistical multiplexers, ATM switch port controllers, etc  相似文献   

15.
The main goal of this article is to present the translation of quality of service (QoS) parameters between layers. The QoS parameters in the ATM layer and AAL are defined. This translation concept came from the QoS framework in which the influence of the protocol stack on the QoS should be considered. As an example, we concentrate on the translation from the AAL to the ATM layer, as the AAL must be designed to be service-dependent and specific. Translation, both taking the transport protocol into account as well as between application and transport QoS, needs further study. However, our study shows that the QoS translation is a possible and good approach in end-to-end QoS guarantees in the broadband integrated services digital network (B-ISDN). As far as the end-to-end QoS guarantee issue is concerned, the transport QoS requirements are specified in terms of bounds on transport QoS parameters. The bounds on transport QoS parameters will be translated into the bounds on ATM layer QoS parameters. The ATM-layer QoS parameters resulting from the translation will be the performance requirements on a connection basis for the ATM network, but are basically the end-to-end parameters, including the network and the end systems. Therefore, the QoS translation finally results in the network performance parameters in the ATM network. We define QoS parameters in the AAL and ATM layer. Case studies in which the translation method is applied to a constant bit rate (CBR) video service and data service, respectively, are also presented  相似文献   

16.
ATM技术是ITU-T推荐的B-ISDN交换技术,而帧中继在提供广域网业务方面很成功。因此,在ATM发展的初期不可避免地会与帧中继技术并存。本文阐述了ATM与帧中继网络互加和业务互连的相关技术及其存在的问题。  相似文献   

17.
ATM adaptation layer protocol   总被引:1,自引:0,他引:1  
The ATM adaptation layer (AAL), as defined in the International Telecommunications Union (ITU) 1990 recommendations, will enhance the services provided by the ATM layer to support the functions required by the next higher layer. The question of what that next higher layer is has been a matter of controversy from the beginning of the AAL study. AAL protocol specifications are key to the success of B-ISDN services. They must be developed in a timely fashion, in cooperation with other standardization bodies such as ISO and the ATM Forum  相似文献   

18.
The the quality of service (QoS) concept is becoming an ever more important issue in telecommunication and computer communication. The article focuses on the QoS notion and concept. The definition of QoS in the International Telecommunications Union-Telecommunications Sector (ITU-T) recommendations and the International Standards Organization (ISO) standards is analysed. Little is known about the asynchronous transfer mode (ATM) performance requirements of the broadband integrated services digital network (B-ISDN) services, especially for multimedia applications. This is because the ATM performance requirements of multimedia applications depend not only on the diverse QoS requirements from application and user, but also on the protocol stacks and scheduling in end systems. Therefore, in order to guarantee QoS to the user, it is necessary to introduce a set of QoS parameters whose properties indicate the nature and requirements of the layered protocol stack. We describe how a proposed QoS framework can be applied to B-ISDN as a specific network. The QoS aspects related to B-ISDN signaling (the control plane) and the QoS aspects related to layer and plane management (the management plane) are described. We also describe how the QoS framework resides in a protocol stack and works together with the B-ISDN network management and signaling  相似文献   

19.
ATM will provide flexibility in bandwidth allocation and will allow a network to carry heterogeneous services ranging from narrowband to wideband services. The challenge is to build fast packet switches able to match the high speeds of the input links and the high performance requirements imposed. The CCITT has standardized the asynchronous transfer mode (ATM) as the multiplexing and switching principle for the broadband integrated services digital network (B-ISDN). ATM is a packet and connection-oriented transfer mode based on statistical time division multiplexing techniques. The information flow is organized in fixed-size packets called cells, consisting of a user information field (48 octets) and a header (5 octets). The primary use of the header tag is to identify cells belonging to the same virtual channel and to make routing possible. Cell sequence on a virtual channel is preserved, a very low cell loss probability must be guaranteed (< 10-12), and intensive error and flow control protocols are provided at the edges of the network  相似文献   

20.
The evolution of public telecommunication networks toward broadband integrated services digital networks (B-ISDNs) is presented. The asynchronous transfer mode (ATM), which supports B-ISDNs, and the B-ISDN protocol reference model are discussed. It is shown that the service offered by the ATM layer in the B-ISDN protocol reference model is equivalent to the service offered by the OSI physical layer. It is also shown that the service offered by the ATM adaptation layer (AAL) type 3/4 is similar to an OSI data link service. The emergence of the metropolitan area network (MAN) standard as an intermediate support for broadband services and the similarities between the DQDB MAC and the AAL type 3/4 in its connectionless mode are discussed  相似文献   

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