The repository shall uniquely identify each AIP within the repository.

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 will be removed.

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