Donald Bren School of Information and Computer Sciences

The transport of connectionless data is necessary for the compatibility of emerging wide area ATM networks with existing computer networks. This paper investigates the design and performance of a virtual connectionless network overlayed on top of cell-based connection-oriented ATM networks. The virtual connectionless network is made possible by utilizing connectionless servers. Two packet forwarding techniques used by connectionless servers are examined. Forwarding connectionless packets in a cell-by-cell manner (streaming mode) is shown to result in lower packet loss and end-to-end delay than packet-by-packet forwarding of connectionless data (reassembly mode). A design and implementation are presented for a streaming mode connectionless server capable of a maximum throughput of 100 Mbps.