Critical infrastructures are organizations and facilities that are of great importance to the functioning of the community and whose failure or impairment would result in significant supply bottlenecks or threats to public safety.

In accordance with the legal provisions, operators of critical infrastructures must provide the Federal Office for Information Security (BSI) with a contact point through which they can be reached at any time. The BSI sends various information to this address, for example warnings on IT security and situation information.

Operators of critical infrastructures that belong to the same sector can also designate a joint higher-level contact point (GÜAS).

In this case, the exchange of information between the operators of critical infrastructures and the BSI generally takes place via this common point of contact.

As a rule, the BSI sends out information during normal business hours. In exceptional cases, urgent warnings can also be sent outside normal business hours, i.e. on public holidays, weekends or at night.