A 622 Mb/s LAN/WAN gateway and experiences with wide area ATM networking

The use of similar technology in local and wide area networks enables geographically distributed high-performance applications. Key elements in achieving high performance are the appropriate use of traffic control and the development of efficient gateways between LANs and WANs. Even though the basic technology used on both sides of a gateway may be similar, the operational aspects of these elements are significantly different. A gateway has been developed and implemented not only to support communications between an ATM LAN and WAN at 622 Mb/s, but also to provide a platform for conducting network control and traffic research. In addition, the performance of the MAGIC WAN was evaluated, and bottlenecks were identified and analyzed. Techniques were developed and implemented, specifically ATM cell-level pacing, to eliminate these bottlenecks. Throughput performance close to the theoretical maximum was demonstrated. This article describes experiences with ATM over a WAN and how the gateway was developed, implemented, and evaluated. The results included show how high-speed LAN/WAN internetworking can be achieved and applied in many environments as appropriate control techniques and interfaces become ubiquitous.