Comparison of the Gigabit Ethernet Full-Duplex Repeater, CSMA/CD, and 1000/100-Mbps Switched Ethernet

Recently, the Full-Duplex Repeater (FDR) has been proposed as an alternative to half-duplex operation using CSMA/CD for controlling shared access to Gigabit Ethernet. In this paper, the basic FDR architecture is described and two extensions for traffic control are introduced. Using simulation methods, the performance of the Gigabit FDR is studied under different topologies and population sizes for a range of offered load. It is shown that the FDR provides a dramatic performance improvement over CSMA/CD (using both BEB and BLAM arbitration) at high load. The Gigabit FDR is also compared with switched Ethernet in the context of medical image retrieval. It is shown that for medical image retrieval, the performance of the Gigabit FDR is much better than 100/100 or 1000/100-Mbps switched Ethernet, and equivalent to 1000/1000-Mbps switched Ethernet for low levels of non-image background traffic.