SURVEY OF TRAFFIC CONTROL SCHEMES AND PROTOCOLS IN ATM NETWORKS

In the past few years, Broadband ISDN (B-ISDN) has received increased attention as a communication architecture capable of supporting multimedia applications. Among the techniques proposed to implement B-ISDN, Asynchronous Transfer Mode (ATM) is considered to be the most promising transfer technique because of its efficiency and flexibility. In ATM networks, the performance bottleneck of the network, which was once the channel transmission speed, is shifted to the processing speed at the network switching nodes and the propagation delay of the channel. This shift is because the high-speed channel increases the ratio of propagation delay to cell transmission time and the ratio of processing time to cell transmission time. Due to the increased ratio of propagation delay to cell transmission time, a large number of cells can be in transit between two ATM switching nodes. In addition, the increased ratio of processing time to cell transmission time makes it difficult to implement hop-by-hop control schemes. Therefore, traffic control in ATM networks is a challenge, and new network architectures (flow control schemes, error control schemes, etc.) are required in ATM networks. This paper surveys a number of important research topics in ATM networks. The topics covered include mathematical modeling of various types of traffic sources, congestion control and error control schemes for ATM networks, and priority schemes to support multiple classes of traffic. Standard activity for ATM networks and future research problems in ATM are also presented.