Measurements in a FDDI workstation cluster

Abstract

We study the throughput characteristics of a FDDI workstation cluster installed at the University of Paderborn. We compare theoretical results to the performance really available to the user at the service access point to TCP and UDP. Furthermore, we compare the performance for two difficult operating systems: we consider the SUN-OS based on BSD and the new Solaris 2.3 developed for multiprocessor environments. The measurement results showed a maximum throughput of less than 60 Mbps which is still considerably less than the bandwidth promised by FDDI vendors. Moreover, it becomes clear that high throughput absolutely requires the transmission of large frames. We also briefly address the current discussion on higher speed LANs within IEEE 802.<>