The efficiency analysis of the swiching fields of an ewsd v.15 digital switching system

Because of wide introduction of EWSD digital switching system on modern telephone networks, the problem of the economic efficiency of its operation is highly compelling. For the solution of this task at the stage of the digital switching system design it is necessary to select an optimal switching field structure. In this work the structures of single-, three- and five-link switching fields of digital switching system EWSD V.15 built on two standard time and three spatial modules at five capacities have been simulated. For the efficiency evaluation of the thirty switching field structures the economic criterion, determined as the cost of one digital channel in equivalent switching points, has been used. As a result of the analysis it has been established that the single-link switching fields of small capacity are more effective. Three-link switching fields are implemented effectively only for small and middle capacities. Besides, they have the quality service of input paths owing to larger connectivity. Five-link switching fields in case of large capacities are ten times less expensive than single-link ones and their cost is nearly the same as the cost of three-link switching fields.