Performance analysis of FDDI as a backend network interconnecting heterogeneous workstations in a distributed system

A simulation model of an FDDI token ring used as a backend network to connect heterogeneous workstations in a distributed system is presented. In order to test the viability of FDDI in such an environment, the model simulates an execution of a 256-point FFT (fast Fourier transform). The process of execution was distributed among heterogeneous stations (SUN SPARC 1⁺ and IBM RISC 6000). The analysis is based on the modeling and simulation of the MAC (media access control) layer, which is the lower sublayer of the data link layer (OSI reference model). Comparing the results obtained from simulation and analytical analysis to those of executing the 256-point FFT on a stand-alone station, the performance of a distributed computing system based on FDDI is better by a factor of 3.45. However, as simulation results show, a station remains idle waiting for a token approximately 98% of the time (versus 2% computing). Reducing the number of stations in this kind of application would decrease the waiting time; however, an optimum solution should be investigated case by case