Asynchronous Transfer Mode Technology Research Articles

Principles and Standards for Broadband ISDN

Broadband ISDN was developed with the goal of providing a multiplicity of services over a standardized interface. The fast-packet technology of asynchronous transfer mode (ATM) makes it possible to transport information with widely differing characteristics, from bursty data services to high-definition television signals, over a range of speeds. With ATM technology, it is possible to build new high-speed networking equipment for the customer. These new products, plus a defined interface to Synchronous Optical Network (SONET) standards, and powerful signaling and control capabilities for multimedia services, are making broadband ISDN the basis for the next generation of network infrastructures. To provide global broadband products and services, international broadband standards are critical. This paper reviews the work of domestic and international standards bodies on a number of important standards for ATM transport, broadband signaling, and other aspects of broadband ISDN, and discusses how industry forums are working to ensure the compatibility of products and services of multiple vendors.

ATM technology: a backbone for high speed computer networking

The use of data communication equipment in local environments is increasing rapidly. Applications such as electronic mail, file transfer, CAD/CAM, etc., currently result in the installation of more and more LANS in offices. Since the industry becomes more and more located at different places worldwide, the interconnection of these LANs becomes more and more a requirement. With the increasing number of applications, higher and higher bit rates are required at those interconnections. Different solutions exist to connect these LANs. Most of them are based on B-ISDN tecniques, using the ATM (Asynchronous Transfer Mode) cell relay principle. The first solution, which is initially applicable in a metropolitan area is based on the MAN (Metropolitan Area Network) technology as standardized by IEEE 802.6. It is based on the DQDB (Distributed Queue Dual Bus) principle, and offers to the customer both high speed data interconnectivity and isochronous services. To cover larger areas than metropolitan ones, MANs can be connected by high speed leased lines, or by an ATM backbone network. An alternative solution, but with some complementarity to MANs, is called an ATM crossconnect network. This solution offers to the customers semi-permanent high speed connectivity. This solution can also be used as an enhancement to MANs, to provide a backbone to connect multiple MANs. Such an ATM crossconnect network can be enhanced with a connectionless server, to offer to the customers full international high speed data connectivity. Both solutions use the ATM transfer mode of B-ISDN and thus allow a gradual evolution to the full B-ISDN, in which each service can demand dynamically its virtual connection (or multiple virtual circuits for multimedia services). To ensure a worldwide connectivity, all involved telecommunication operators have to plan the necessary coordination.

Frame relay and SMDS services on a common ATM-based platform

The evolution to broadband networking in the world market has started, enabled by the evolution of the transmission infrastructure and new switching techniques. The market is being driven by the high-speed requirements imposed by the unprecedented penetration of LAN technology and associated high-speed applications as well as the integration of voice, data, image and video requirements. The rapid deployment of more reliable, often fiber-based, facilities migrating to the Synchronous Digital Hierarchy (SDH) and the introduction of switching techniques such as Frame Relay and Asynchronous Transfer Mode (ATM) make possible the introduction of networking capabilities to satisfy emerging requirements. Frame Relay services rely on a stream-lined protocol implementation that makes advantage of end-to-end error control strategies to simplify network processing and enable higher throughput and lower delay. Frame Relay services are being targeted at the 64 Kbps to E1 range. The Asynchronous Transfer Mode (ATM) has been accepted as the transport mechanism for the future Broadband Integrated Services Digital Network (B-ISDN). Metropolitan Area Networks (MANs), based on IEEE 802.6 ATM principles, represent the first commercial application of ATM technology. An early MAN service is the Switched Multimegabit Data Service (SMDS) 1 which has been specified to provide efficient high-speed data transport in the E1 to 34 Mbps range with future extensions to incorporate isochronous transport for the addition of constant-bit rate services such as voice and video services. Similar to SMDS, Connectionless Broadband Networking Services (CBDS) are being defined by ETSI for the European Market with input from the European SMDS Interest Group (ESIG). This paper presents an ATM-based architectural approach, as implemented in At&T's Broadband Networking System 2000 (BNS-2000), to provide Frame Relay as well as SMDS services on the sam platform. The BNS-2000 represents a growable and modular architecture that has been built to comply with international standards such as ANSI, CCITT and ETSI to support the emerging needs of the market.

ATM technology for corporate networks

Asynchronous transfer mode (ATM) technology is discussed in relation to the requirements of corporate networking. An introduction to ATM switch architecture is presented. The various approaches to ATM switch design that have appeared in previously published literature are reviewed. A discussion is presented of some current issues facing the development of the ATM networks. It is argued that much simpler solutions to many of these issues may be adopted in the context of the corporate network than is permissible for the public broadband network. >

Implementing the Orwell protocol over a fibre-based high-speed ATM network

Asynchronous transfer mode (ATM) has emerged as a possible contender for the next generation switching system and fundamental transport basis for the broadband integrated services digital network (B-ISDN) and telecommunications in the future. It is widely thought of as the network to accommodate the uncertain requirements of future public communications because of its high degree of flexibility and service independency. The Orwell protocol developed by British Telecom can provide a communication base to meet the requirements of such a network. Orwell is used here as a slotted ring protocol designed to carry a mixture of services which form the basis of an ATM network. The paper describes the realisation of a 155.52 Mbit/s fibre-optic physical layer from the Orwell protocol based on an ATM technology, and also discusses how the Orwell protocol can offer broadband transport capabilities and can provide access to and interwork with existing networks, such as telephone networks and 64 kbit/s based ISDNs.

Ratt: a glimpse of a broadband future

The ATM Technology Testbed being built by the partners of the RACE Project R1022 and due to be operational in Basel by mid 1993 is described. The result of five-years work by the project team, this testbed will provide a vehicle for advanced experiments that will lead to a greater understanding of the properties of large asynchronous transfer mode (ATM) systems. Included in the paper is an overall description of the system and its constituent building blocks, as well as an outline of the experiments that will be performed on it.

Alloys of aluminum and zinc

The evolution to broadband networking in the world market has started, enabled by the evolution of the transmission infrastructure and new switching techniques. The market is being driven by the high-speed requirements imposed by the unprecedented penetration of LAN technology and associated high-speed applications as well as the integration of voice, data, image and video requirements. The rapid deployment of more reliable, often fiber-based, facilities migrating to the Synchronous Digital Hierarchy (SDH) and the introduction of switching techniques such as Frame Relay and Asynchronous Transfer Mode (ATM) make possible the introduction of networking capabilities to satisfy emerging requirements.Frame Relay services rely on a stream-lined protocol implementation that makes advantage of end-to-end error control strategies to simplify network processing and enable higher throughput and lower delay. Frame Relay services are being targeted at the 64 Kbps to E1 range. The Asynchronous Transfer Mode (ATM) has been accepted as the transport mechanism for the future Broadband Integrated Services Digital Network (B-ISDN). Metropolitan Area Networks (MANs), based on IEEE 802.6 ATM principles, represent the first commercial application of ATM technology. An early MAN service is the Switched Multimegabit Data Service (SMDS)1 which has been specified to provide efficient high-speed data transport in the E1 to 34 Mbps range with future extensions to incorporate isochronous transport for the addition of constant-bit rate services such as voice and video services. Similar to SMDS, Connectionless Broadband Networking Services (CBDS) are being defined by ETSI for the European Market with input from the European SMDS Interest Group (ESIG).This paper presents an ATM-based architectural approach, as implemented in At&T's Broadband Networking System 2000 (BNS-2000), to provide Frame Relay as well as SMDS services on the sam platform. The BNS-2000 represents a growable and modular architecture that has been built to comply with international standards such as ANSI, CCITT and ETSI to support the emerging needs of the market.