In the first case, encrypting data on a device and then transferring it in encrypted form to the cloud is sufficient. However, should information be shared with third parties, as in the second case, the secret key would have to be distributed through some safe channels or by centralized key administration. Transferring the key through unsafe channels (e.g., a password by e-mail), can lead to undesired eavesdropping through robots and third parties. However, should the data not only be stored but also processed in the cloud, data encryption is necessary once it has been transferred to the cloud. This is because data processing requires, with the exception of so-called homomorphic encryption, that the data is available in plain text. Usually at this point, the administrators of the cloud, as well as the cloud application, have direct access to the confidential data. Consequently, that kind of data processing requires trustworthy providers and administrators. The special feature of the sealed cloud is that it logically, electronically and mechanically prevents the operators or administrators from accessing the data during processing. Thus, the sealed cloud creates the possibility to process confidential data in the cloud. idgard® applies this new basic technology to enable secure communication via sealed privacy boxes without complicated key management.