Considerations on analog and digital electronic switching networks and their applications

It is expected that electronics will play a major role in the next decades in the implementation of switching networks for telephone exchanges, as it has already happened both in transmission and exchange control [1]. Making use of many results of the referenced literature, some considerations are presented in order to compare electronic analog and digital switching networks for telephone exchanges. Some of the highlighted aspects show the more significant tradeoffs to be considered when choosing an electronic switching network. Electromechanical switching is not considered here, but some reference is made when necessary. After some preliminary analysis of the telephony signals and their impact on the design and the characteristics of the switching networks, typical problems of practical relevance are then considered. Furthermore, a general comparison between the various techniques is discussed from an economical point of view, with reference to local and transit application areas.