| 摘要 |
A first installation stores a secret key of a user and a second installation provides encrypted data for the user. In order that a user apparatus can decrypt the encrypted data, the apparatus creates a one-time password, encrypts the one-time password by means of a public key of the first installation and causes the second installation to retrieve the secret key of the user from the first installation by means of the encrypted one-time password and a key identification allocated to the user in the second installation. The first installation decrypts the one-time password, searches for the secret key based on the key identification, encrypts it with the one-time password and transmits the encrypted secret key to the apparatus via the second installation. There, the secret key of the user is decrypted by means of the one-time password and is used for decrypting the encrypted data. |
