A GPSS simulation to determine congestion in an ethernet type local area network
Howard Blums, Frank Paccione · Winter Simulation Conference · 1984
A large bank has approximately 1000 terminals in a single building which perform transactions on several computer systems concentrated in a single data center. Cabling, modems and switching are required to support each terminal connection. The current methods of communication have led to congestion in the building's cabling conduit system and high per terminal costs for switching facilities, modems and relocation of terminals.A bus type local area network is being considered as a solution to these problems, but due to the newness of this technology, experience with an installation of similar size and characteristics appears as yet unavailable. Congestion of the network due to contention for access to the bus is a major concern.We describe a relatively simple model of the workload and communications bus operation developed to study the frequency of bus contention. A GPSS simulation program and results are presented for this model. In addition, an even more simplified analytical queueing model is used to bound the frequency of contention for the bus and the result is compared with that of the simulation.