trusted computing base (security) (TCB)

The Trusted Computing Base (TCB) is a system component that contains all the computer's security-relevant functions and does not allow access from outside.

The Trusted Computing Base (TCB) is used to increase security and is provided with protection mechanisms that are reflected in the integrity of the operating system and all relevant hardware modules. The Trusted Computing Base is the central component for increasing security over the relevant product or system and is dependent on appropriate TCB mechanisms and the correct entry of parameters by the system administration.

In a TCB configuration, if a connected terminal wants to have a secured communication connection to a secured node, it sends an Attention Character to the Trusted Computing Base.