The metadata of a digital object should be rich enough that a machine or a human user can make an informed decision upon discovery whether the digital object should be used within the requested context or not. The included metadata should inform the user about the license and the resulting usage conditions of the bit sequence or the metadata itself. This metadata should be machine-readable to facilitate automated data harvesting, while ensuring the proper attribution of provenance information to enable correct citation. Metadata should also provide information about any form of access control and, if applicable, the authentication protocol required for access, so that users can determine which components of the data they are allowed to access.