Architecture and performance of asynchronous transfer mode networks for data traffic

The last decade has seen a prolific growth of data traffic over computer networks including the Internet and private intranets. The standard local area network technology, Ethernet, has evolved to meet the bandwidth needs of ever-hungry applications. However, Ethernet is not well suited for wide area communications. Asynchronous Transfer Mode (ATM) networks have become for many the backbone technology of choice. However, ATM networks have not yet been efficiently utilized to its full potential. ATM was designed as a multimedia, multiservice network but designed primarily for connection-oriented, semi-bursty applications such as videoconferencing. The efficient delivery of connectionless and highly bursty data traffic over ATM is a challenging problem that has been intensively investigated by numerous researchers in the past few years.; A number of approaches have been proposed to provide connectionless datagram transport over the connection-oriented ATM network. Among these are Classical IP over ATM, LANE, MPOA, flow switching, and the direct and indirect approaches of the ITU. This dissertation investigates the architectures of performance of two generic models for data over ATM: a server based model and a connection based model. The resource usages of the two models and the performance of design of connectionless servers are analyzed. Numerical results of mathematical analysis and simulations illustrate environments where one approach or design performs better than others.; The transport of data over ATM, regardless of whether a server based or a connection-based approach is utilized, must contend with network congestion. In ATM networks, the Available Bit Rate (ABR) service enables the smooth integration of data traffic with the more delay and loss sensitive real-time traffic. In addition to the flow and congestion control provided by ABR, legacy data applications utilize TCP flow control which provides end-to-end reliability and, indirectly, congestion control. This dissertation also investigates the performance of TCP over ABR traffic. In a comparison of rate based ABR schemes, EPRCA and ERICA, and a credit based ABR scheme, QFC, it is shown that the performance may be significantly better with QFC than previously thought when bursty traffic sources and preemptive interfering traffic is considered.