Sometimes, concepts can be tools. The OAIS (Open Archival Information System) is a model for preserving, managing, and sharing digital objects in the long term. NASA, along with the space agencies of a few other countries, had just developed a way to preserve information collected about space when the ISO (International Organization for Standardization) asked the group to extrapolate their ideas to create standards of long-term preservation relevant to any organization. The result is the diagram at right of how an archive should function.

It is easy to understand this process if you look at the three stages that digital items go through in an OAIS-based system —SIPs, AIPs, and DIPs.


Submission Information Packages consist of the object you want to preserve, descriptive and technical information about that object (called metadata), and further information about how the object and its metadata have been packaged together. This digital bundle represents the beginning of the preservation process.


Similarly, Dissemination Information Packages represent the end of the preservation chain of events. These digital bundles contain objects and information that you have requested from the OAIS, and they are usually access copies of a digital item and associated metadata.


Archival Information Packages are where the archival material itself lives. Upon ingestion into an OAIS system, the SIP becomes an AIP—the digital object, perhaps also a copy or reformatting of the object, metadata, specific authentication data, and preservation-oriented packaging—the digital bundle in an archival state. It is what is retained for long-term preservation.