7. Overview of some systems

For practical reasons of pedagogy and greater precision in the descriptions, we have based the presentation of the architecture of a digital automatic exchange on the Alcatel E10 system, which equips a very large part of the France Télécom network and is installed in many other networks. This made it possible to use fairly detailed architecture diagrams for a better approach to the problems.

We will now present the general architectures of three other well-known switching systems, which are also used in large networks.