It is in this respect the underlying recognition of the invention that the security of the embedded device can be greatly increased if the embedded device is itself equipped with security functions. For this purpose, the functions of the embedded device are divided into functional blocks that are in turn associated with levels disposed above one another hierarchically. In order, for example, to access a level below the topmost level, an authentication must first take place for the topmost level. Subsequently, another authentication has to be carried out for the lower level.

The security mechanism thus implemented is based on a layered principle that makes multiple authentications necessary for functions in lower levels. The security, in particular of functional blocks in lower levels, is considerably increased on the basis of the optionally required multiple authentication.