M/M/m modelling of access delay to X.25 virtual circuits

An effort is made to analyze the admission delay of an X.25 connection, modeling the virtual circuit as an equivalent server with parameters related to the behaviour measurable by the X.25 user. The authors review M. Reiser´s (1978) mean value analysis of a virtual circuit with window flow control, Norton´s theorem is used to obtain an equivalent server allowing the evaluation of the X.25 admission delay. An M/M/m system is proposed as an approximate equivalent system of the X.25 virtual circuit, which produces a very tight and conservative bound of the actual performance