ATM in MPLS-based converged core data networks

Services supported by asynchronous transfer mode account for the majority of data and Internet service revenues generated by carrier networks today. This is based on ATM's ability to support high availability services with quality of service. However, the influences of the Internet and a highly dynamic telecommunications market have raised demands for increased flexibility while controlling costs. Therefore, future carrier networks are likely to continue to be based on established technologies, such as ATM, as well as IP. In many cases, this is achieved through maintaining separate ATM and IP core networks, with the IP network supporting Internet services, while the ATM network continues to support guaranteed services such as private lines, broadband access, and video. In some cases, however, it can be advantageous for a carrier to transport segments of their ATM network over their IP network core; for example, to transport ATM traffic currently carried on leased facilities onto an IP network where the service provider owns the facilities. Developments in IP and MPLS-based traffic engineering and QoS may increase the ability of IP-based networks to support ATM services using MPLS. This article provides an overview of approaches enabling a network based on MPLS that naturally supports IP services to also support ATM services. The drivers and requirements for convergence on an IP/MPLS core network are presented, followed by an overview of the different approaches and associated challenges currently being debated in the standards bodies.     

IP/ATM integrated services over broadband access coppertechnologies

A rich set of broadband access copper technologies is available in the market today, and more are coming out of the laboratories, rapidly moving to standardization. The most likely future scenario will be one where many different technologies coexist. This multi-access-technology paradigm poses an interesting internetworking problem where interoperability and capability to support today's and future user services play a major role in the design of a network architecture. This article begins with an overview of current and new xDSL access technologies to continue describing an access network design that harmonizes the interconnection between PON, xDSL, and native ATM transport technologies. The use of ATM technology for the interface to the broadband access and transport networks is then presented and justified. The article continues studying the protocol architectures proposed for access to network service providers, considered a driver application for broadband access deployment. Finally, different protocol architectures that can provide integrated services support at the user equipment are analyzed     

A vision for residential broadband services: ATM-to-the-home

The arrival of asynchronous transfer mode (ATM) networks has enabled a wide range of new interactive multimedia applications for the residential market. The article presents a vision for supporting universal residential broadband services based on an ATM-to-the-home (ATTH) network architecture. This network architecture applies to the various residential access network (RAN) architectures being deployed today, such as hybrid fiber/coax (HFC), fiber-to-the-curb (FTTC), fiber-to-the-home (FTTH), and asymmetric digital subscriber loop (ADSL) technologies. The article addresses today's residential networks and applications, to understand why a switched broadband residential network is required to support residential broadband services. After exploring residential broadband application requirements, a new class of service is proposed to support a very important class of residential broadband applications that has been not addressed. Then, the technical and strategic motivations for using the ATTH architecture are discussed in detail. A universal model for residential broadband network architecture based on ATTH is described, which is shown to apply to various RAN architectures. Finally, it discusses the signaling requirements of residential broadband services and explain why the ATM multiconnection per-call model is much more efficient than the digital stored media command and control (DSM-CC) session control protocol approach for the ATTH architecture     

Evolution towards an ATD multiservice network

Public networks will continue to evolve in order to provide additional services and to make use of emerging technologies. This evolution is being directed toward multiservice networks which allow the cheaper introduction of new services. Asynchronous time division (ATD) techniques are preferred as the basis for implementing multiservice networks, such as LANs, because they can provide full service integration, rate adaption and the statistical multiplexing of variable bit rate services. This paper outlines some gradual evolutionary paths which are directed toward a single ATD multiservice network and could provide immediate benefits. An eventual ATD network could be expected to use short fixed length packets, a mixture of datagram and virtual circuit techniques and a mixture of switch architectures in order to most economically meet the requirements of a public network. The Orwell protocol, developed within British Telecom, provides a means of meeting the performance requirements of such a network.     

The infrastructure for gigabit computer networks

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     

Broadband satellite networks-the global IT bridge

Next-generation broadband satellite networks are being developed to carry bursty Internet and multimedia traffic in addition to the traditional circuit-switched traffic (mainly voice) on a global basis. These satellites provide direct network access for personal applications as well as interconnectivity to the terrestrial remote network segments. The main requirement in success of these networks is that they should be able to transmit high data rate traffic with prescribed quality of service (QoS). Thus, the broadband satellite network has no choice other than the rise of ATM technology and to be optimized for Internet-based traffic. ATM is the promising technology for supporting high-speed data transfer potentially suitable for all varieties of private and public telecommunications networks. IP, on the other hand is the fast-growing Internet layer protocol that is applicable over any data link layer Internet-based applications are the emerging source of traffic in the future wireless networks and broadband satellite networks should consider Internet as the primary service. In this paper, we discuss the traditional ATM and wireless ATM networks and explain the characteristics of the wireless IP networks. The paper then uses those concepts in defining the criteria for the broadband satellite networks such as the QoS and traffic management. Application of the broadband satellite networks is also proposed     

ATM-based transport architecture for multiservices wirelesspersonal communication networks

This paper presents an ATM-based transport architecture for next-generation multiservices personal communication networks (PCN). Such “multimedia capable” integrated services wireless networks are motivated by an anticipated demand for wireless extensions to future broadband networks. An ATM compatible wireless network concept capable of supporting a mix of broadband ISDN services including constant bit-rate (CBR), variable bit-rate (VBR), and packet data transport is explored from an architectural viewpoint. The proposed system uses a hierarchical ATM switching network for interconnection of PCN microcells, each of which is serviced by high-speed, shared-access radio links based on ATM-compatible cell, relay principles. Design issues related to the physical (modulation), media access control (MAC), and data-link layers of the ATM-based radio link are discussed, and preliminary technical approaches are identified in each case. An example multiservice dynamic reservation (MDR) TDMA media access protocol is then considered in further detail, and simulation results are presented for an example voice/data scenario with a proportion of time-critical (i.e., multimedia) packet data. Time-of-expiry (TOE) based queue service disciplines are also investigated as a mechanism for improving the quality-of-service (QoS) in this scenario     

Satellite ATM networks: a survey

Satellite ATM networks have significant advantages over terrestrial ATM networks. Satellites provide unique advantages such as remote coverage with rapid deployment, distance insensitivity, bandwidth on demand, immunity to terrestrial disasters, and offering broadband links. Satellite ATM networks will play an important role in the rapidly evolving information infrastructure. However, there are several obstacles which need to be overcome so that satellite ATM networks can operate in full service. The objective of this survey is to present the state of the art in satellite ATM networks and to point out open research problems. We explain the satellite ATM network architecture and cover the requirements and technical barriers for seamless integration of ATM and satellite networks. We describe the feasibility of the existing ATM cell transport methods, and deal with conventional and new satellite link access methods, and some error control schemes for the satellite environment. We then describe the problems of the proposed traffic and congestion control schemes, followed by the error performance of the Transmission Control Protocol (TCP) and Service-Specific Connection-Oriented Protocol (SSCOP) for the satellite ATM network. We present basic requirements and a possible architecture for local area-metropolitan area network (LAN-MAN) interconnection using satellite ATM and then discuss the requirements for multimedia services in satellite ATM networks     

Traffic management for B-ISDN services

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     

Securing multimedia services over satellite ATM networks

In recent years there has been increasing interest in interconnecting satellite and ATM networks, because both share common characteristics of the ability to provide bandwidth-on-demand and flexibility of integrating voice, video and data services. There are several new satellite constellation proposals that support multimedia service and transport ATM traffic. For a successful implementation of such systems it is essential to address the security requirements of users, satellite ATM network operators and multimedia service providers. In order to minimize delay and the cost of implementing security systems for satellite ATM networks, the network operator role (in security services) can be limited to the mutual authentication with satellite users during call set-up periods. In this paper a mutual authentication protocol between the user and the satellite network is presented using digital signature and public key systems. Also, another mutual authentication protocol between the user and the service provider is presented to provide end-to-end authentication and negotiation of security options such as selecting a secret key system and the key length. Finally, a detailed hardware implementation of ATM cell payload encryption is presented using the DES/TripleDES secret key system. © 1998 John Wiley & Sons, Ltd.     

CATV网渐进升级为全业务接入网的技术

本文就ＣＡＴＶ网向宽带全业务网升级的策略和技术进行了讨论。首称要将现有ＣＡＴＶ网改造为双向传输网。在此基础上,建成ＣＡＴＶ广播网和计算机网并行的网络。在计算机网中,应用Ｃａｂｌｅ ｍｏｄｅｍ实现数据双向传播,或在ＣＡＴＶ网中应用暂时富裕的光纤构成独立计算机网。     

The Broadband Access Facility

The deployment of broadband access networks will revolutionise many aspects of society in the early years of the next millennium. Manufacturers, telecommunications providers and cable television operators world-wide are investing heavily on research into networks that provide broadband multimedia services to customers. BT has developed a prototype of a full service access network that can connect customers via optical fibre, digital subscriber line or radio technologies. This paper describes the physical implementation of the prototype network and the wide range of services that it can support.This prototype network, referred to as the 'broadband access facility' is enabling BT and its partners to understand the best access architectures for a given environment through practical testing. The network now serves as an experimental platform, that can be used for communicating broadband concepts, designing operational processes, developing management solutions and testing advanced applications.The full service access networks (FSAN) initiative is a collaboration involving fourteen of the world's leading telecommunications network operators and major equipment manufacturers. Its vision is to create a shared requirements specification for access systems supporting narrowband and broadband services. This common specification will mean that broadband network components can be developed for world markets, thus raising volumes and driving down unit costs. The common system specification is based around an ATM/SDH (asynchronous transfer mode/synchronous digital hierarchy) core network, with local optical fibre distribution via an ATM PON (passive optical network). DSL (digital subscriber line) systems maximise reuse of existing copper plant. The exact DSL system used depends upon where the optical system is terminated, e.g. in the local exchange, cabinet, kerb or home. Hence this broadband access system can support a range of access architectures — this flexibility is fundamental to the consensus achieved in FSAN.     

MLAP: a MAC level access protocol for the HFC 802.14 network

Interactive residential broadband/multimedia services are expected to be the next main event in the cyberspace experience. The large excess bandwidth (well over 300 MHz) available in today's cable TV (CATV) hybrid fiber/coaxial (HFC) plants is an ideal candidate to provide the underlying communications infrastructure for interactive digital services to the home; cable operators that have not yet upgraded their all-coaxial plants to HFC are quickly moving in this direction. MLAP is a flexible ATM-friendly MAC protocol that is capable of supporting various types of traffic with diverse quality-of-service requirements. We introduce a very versatile MAC protocol for the HFC 802.14 network. MLAP can provide integrated broadband services to the home, internetwork easily with ATM wide area networks, support QoS constraints for various types of traffic, and operate over a variety of physical layer protocols. Our presentation is only an extended summary of our medium-sharing protocol proposal to the IEEE 802.14 WG. We consider only error-free system operation. MLAP provides for the use of timers for the recovery of error situations in the network. MLAP is also supported by a management suite of protocols for management of the overall system     

ATM and the future of telecommunication networking

Telecommunication services and networks are in the process of significant change. This paper examines whether asynchronous transfer mode (ATM), thought at one time to be the only viable broadband communication protocol, providing end-to-end connectivity for all applications, still has a role to play in the evolving telecommunication environment. The paper considers the trends in network integration, the emergence of many new services, and the alternative communication protocols with which ATM must compete or interwork. It also addresses the fundamental issue of how to develop a reasonable pricing strategy for these integrated multiservice networks. Several examples are given which show how ATM is adapting to accommodate changing requirements, whilst maintaining its essential ability to transport a diverse range of services. In addition, the authors make a tentative proposal about how economic forces could be harnessed to form a new integrated service model that is compatible with a network infrastructure based upon ATM or any suitable alternative     

Transport architecture evolution in UMTS/IMT‐2000 cellular networks

Mobile evolution from the second generation (2G) to the third generation (3G) raises several important questions for operators and manufacturers. How to ensure that the old and current investments can still be utilized in the future? What is the optimum architecture? ATM or IP? Voice or data? There is no single correct answer to these questions, as it all depends on individual cases. In this paper, we discuss the transport architecture evolution for the universal mobile telecommunications system (UMTS)/international mobile telecommunications—year 2000 (IMT‐2000), or 3G cellular networks and interworking aspects between 2G and 3G cellular networks. The interfaces between access nodes in a cellular network and the changes incorporated to support packet data services are described. Emerging services such as mobile data, virtual private networks (VPN) and location aware networking are described. Role of ATM and IP in this new transport architecture is presented. Control and data plane interworking issues between different transport technologies are described. The new ATM standard, ATM adaptation layer type 2 (AAL2) and its applicability for transporting compressed speech in an ATM based cellular network is described. A similar approach in IP, multiplexing in real‐time transport protocol (RTP) payload to transport compressed speech on selective interfaces of 3G network, is introduced. Transport network architecture evolution within four different scenarios is evaluated. Special interest is focused on the protocol stacks and flexible layered solutions that allow smooth migration from one transport technology to another. Copyright © 2000 John Wiley & Sons, Ltd.     

无线ATM技术的研究

为使无线个人通信具有较大的系统容量和能灵活地处理多种宽带业务，在未来的个人通信中采用ＡＴＭ的传输与交换是一种必然的趋势。本文基于ＡＴＭ网络技术，提出了无线ＡＴＭ网络协议参考模型和网络实现体系结构，并探讨了在无线通信体制下的集成智能网络协议模式与实用虚拟网络结构。     

B-ISDN and the OSI protocol reference model

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     

FUTURE MULTIMEDIA COMMUNICATIONS VIA SATELLITE

We are now moving into an era when conventional speech service will expand to full multimedia service offerings. This paper looks at ways in which satellite systems could provide such services in both the mobile as well as the fixed bands and the integration and inter-operability of such systems. Provision of multimedia services by ATM to integrate with an ATM core network is taken as the basis of the future network. Some of the constraints and difficulties of provision of ATM over satellite are discussed as well as some potential solutions for the ATM wireless protocols and network architectures which potentially could provide such services. Finally, some suggestions of how new orbit constellations could help meet these requirements are given. © 1996 by John Wiley & Sons, Ltd.     

The ATM layer chip: an ASIC for B-ISDN applications

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     

Quality of service in telecommunications .II. Translation of QoSparameters into ATM performance parameters in B-ISDN

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