Abstract: The invention relates to a tele- and data communication system, including circuits containing transfer paths for data flows, and having functionality for error isolation of parts of the system. At least partially, where possible, parts of the circuits of the system are error isolated by logical partition into function blocks of two types. More particularly there is a first type, in which a complete corresponding function block need not necessarily become eliminated by an occurring error, and a second type in which the contrary is true. The transfer paths of a function block of the first type are isolated from each other for enabling shutting down such an erronous transfer path from traffic by software control.