The repository shall uniquely identify each AIP within the repository.

This is necessary in order to ensure that each AIP can be unambiguously found in the future. This is also necessary to ensure that each AIP can be distinguished from all other AIPs in the repository.

Documentation describing naming convention and physical evidence of its application (e.g., logs).

A repository needs to ensure that there is in place an accepted, standard naming convention that identifies its materials uniquely and persistently for use both in and outside the repository. The ‘visibility’ requirement here means ‘visible’ to repository managers and auditors. It does not imply that these unique identifiers need to be visible to end users or that they serve as the primary means of access to digital objects. Ideally, the unique ID lives as long as the AIP; if it does not, there must be traceability. Subsection 4.2.1 requires that the components of an AIP be suitably bound and identified for long-term management, but places no restrictions on how AIPs are identified with files. Thus, in the general case, an AIP may be distributed over many files, or a single file may contain more than one AIP. Therefore identifiers and filenames may not necessarily correspond to each other. Documentation must represent these relationships.

APTrust puts the requirement to maintain the uniqueness of the submitted bag names on the depositor.

Upon ingest to the APTrust repository, the bag is assigned an identifier. APTrust object identifiers use the pattern <institution.domain>/<object_name>, where object_name is the name of the tarred bag, minus the .tar extension. The object record gets created in Registry.

APTrust does not support bag versioning. If a bag is submitted with the same name, Registry will process it as an update to an existing object. Any new files will be added but no files This is necessary in order to ensure that each AIP can be unambiguously found in the future. This is also necessary to ensure that each AIP can be distinguished from all other AIPs in the repository.will be removed.

See Premis Events, Bagging requirements, Intellectual Objects, and Updates for details.