The master files are stored in a sustainable manner. This means that they are stored in such a way that they can be used again in the long term, even if computer technologies and file formats change in the future.
The KB has developed a special storage system for sustainable storage; the e-Depot.
The derivatives and text files are stored in a separate file system intended for the storage of files that are presented on a website. A resolver (pdf) translates each URL to the physical file location. The metadata are stored in an database.