Point-to-Point Loss in Link Systems: Model and Calculation Methods

The switching networks of modern telephone exchanges are often built as multistage arrays which are controlled by conditional selection. Thereby, the strategy is often applied that a certain inlet in stage 1 is to be connected with a certain outlet m the last stage. The traffic loss due to nonavailability of an idle path between the two points is called point-to-point loss or point loss. A traffic models for the calculation of the point loss is defined. Then approximate methods of calculating the point loss in threeand four-stage link systems are derived. The results of calculation are compared with those obtained with a full-scale simulation of the systems investigated.