Performance Bottleneck of TCP/IP over ATM in Local Area ATM networks

Asynchronous Transfer Mode (ATM) is accepted as the suitable technique to realize the concept of Broadband Integrated Service Digital Networks which support diierent kinds of services such as voice, video and data in the future. However, from the economic point of view the new ATM technology has to inter-work with other existing network technologies such as TCP/IP in which the worldwide computer network, Internet, is based. Therefore the performance issue of the Internet Protocol stack TCP/IP over ATM is of great importance. In this paper, we present some TCP/IP-over-ATM performance results carried out in our experimental ATM laboratory consisting of one ATM switch and several workstations equipped with ATM interface cards. The measurement results quantitatively identify some factors (TCP/IP implementation, computer speed, computer cache speed, sender and receiver socket buuer size,...) which cause the performance bottleneck of TCP/IP protocol in ATM networks.