8 - ATM technology and design

Abstract

Asynchronous Transfer Mode (ATM) is a cell-relay technology that builds on some of the benefits of fast packet switching, and provides basic multiplexing and circuit switching. ATM is the first technology that claims to integrate LANs and WANs, and voice and data. It also scales to very high speeds and is adopted by all the leading equipment manufacturers for LAN, WAN, and PBX products. ATM is the solution to the ever-growing demand for bandwidth, which is generated by more sophisticated applications that integrate various combinations of voice, data, video, and image. Multimedia applications require high bandwidth and real-time transfer of information with minimal delay variation and ATM has the required characteristics to support these applications, together with true bandwidth scalability. Cell relay combines the high throughput and bandwidth optimization of Frame Relay with the predictability characteristics of time division multiplexing that makes it suitable for bursty legacy data traffic, isochronous voice, and video traffic. ATM is both a local and wide area transport technology. ATM technology is deployed in public networks and by service providers for a new generation of scalable backbone networks. At the interface between public and private networks, a new breed of WAN switches has emerged that use high-speed switching fabrics to provide self-routing, nonblocking, and scalable switching at multigigabit throughput rates and have the potential to support gigabit port speeds.