Exact and approximate models to obtain average throughput of the FDDI MAC protocol - Part II: asymmetric systems

Abstract

The complexity of the FDDI MAC protocol has made its exact analysis extremely difficult. More often than not, statistical approaches to the problem have produced complex approximations which are both time consuming to compute and are restricted to only very simple network configurations. In the second part of this two-part paper, we propose an alternative approach for computing the approximate mean throughput of a multiple priority asymmetric FDDI network with both synchronous and asynchronous transmissions. The main attraction of the approach is its simplicity and its ability to handle a wide range of network configurations in especially difficult cases where stations are not identically loaded. This makes the approach particularly useful to network designers and administrators who often require quick performance estimates for network configurations that are more complex than those permitted by statistical methods alone. Results of extensive computer simulations used to verify the accuracy of our approach are also presented. The approach presented here for asymmetric networks complements the results presented in Part I of the paper, which is applicable to symmetric networks. © 1994.