NEASIM: A General-Purpose Computer Simulation Program for Load-Loss Analysis of Multistage Central Office Switching Networks
R. F. Grantges, N. R. Sinowitz · Bell System Technical Journal · 1964
Blocking probability is the most frequently required performance characteristic in traffic studies of complex central office switching networks. Determining this quantity without actual measurement is a difficult task. To aid the communications system designer, a simulation program has been prepared which produces useful estimates of blocking probability for a large class of networks. The program is based on a simplified mathematical model for the analysis of switching networks developed by C. Y. Lee, and thus differs from conventional simulators in that it simulates a mathematical model rather than a traffic-handling system. Although Lee's model is widely used, its utility has been limited by computational difficulties encountered in networks of realistic size and complexity. This limitation is in most practical cases removed by the program, which features rapid input preparation, short computer runs, and specification of the desired precision of the results as an input parameter. Moreover, the program allows for the incorporation of more a priori information about the actual behaviour of switching networks than is included in Lee's model, thereby leading to a more accurate estimate of blocking probability. The simulator has been programmed for the IBM 7090 computer, but the concepts are machine independent