The Time-Division Multiplex Switching of Digital Speech Channels

PCM transmission and PCM switching cooperate economically in so-called integrated networks (integrated switching and transmission (IST)). Economical and technical aspects are ruling the introduction of IST. Possibilities of introduction were investigated for the various network levels in the Federal Republic of Germany. It was proved that first of all PCM tandem exchanges are required to which up to 5 000 speech circuits can be connected. A PCM switching network of T-S-S-T structure is being developed for such application within the scope of the EWS 1 system.