An asymmetrical encryption process can therefore be used to generate the key and to verify the key. The public and private keys belong together and form a key pair. The random number can differ for every authentication process, whereby a hacking of the keys transmitted to the embedded device also does not produce a successful attack. The embedded device releases the respective functional block when the respective generated random number and the decrypted key are the same.

Alternatively, a symmetrical encryption process can also be used for authentication at a level. The random number can in particular be encrypted and decrypted using the symmetrical encryption process for this purpose.

The input of a password to carry out an authentication for a level can also take place as a further alternative. A combination of the input of a password and the additional use of a cryptographic process can likewise take place.

The embedded device can preferably provide a web server via which the functional blocks of the embedded device can be accessed. The access can in particular take place by means of an internet connection, with a browser being used to present the contents transmitted from the web server.

If, for example, an asymmetrical encryption process is used for authentication, for example, a public key required for this purpose can be stored or installed as a certificate in the browser, whereby the authentication can take place at the embedded device without any interaction of a user. A separate certificate can preferably be used for each level, which further increases the security of the embedded device.