# eXtended Metadata

There is currently a basic metadata version in LIBSAFE, which, depending on the specifications made at the time of creating the preservation plan, are defined and contain a series of descriptors that are used to present additional information about the object files. From this point on, there is a need to present more information related to the application processes, processes prior to ingestion, processes of enrichment of the object data in the process and subsequent ingestion or any other event that happens on the queried object. In addition, this functionality can be managed directly on the information catalog of the preserved object, so the new functionality is not part of the process of creating a preservation plan, but of the visualization and post-management of an object.

In the same way it is necessary to define a simple and hierarchical scheme to store the resulting information during the process and all types of data received in this section in a homogeneous way. For this purpose, a data hierarchy is established to manage the extended metadata; Class à Type à Set à Block. This latter is in charge to storing all the specified information of each object with the possible variation between two extended metadata classes: Structured or Free.

To ensure data traceability and data preservation over time, the system is required to keep versions of blocks and no editing is allowed on an existing one. Similarly, the blocks will not be stored in the database, but will be stored in files with a defined structure and a specific directory path.

This section defines all the technical concepts that cover the functionality and that are relevant for the management or knowledge of the technical limitations. Therefore, it is essential that these concepts are clear when configuring this functionality.

