The PAC platform respects the standards and practices in the domain. It is particularly consistent with the OAIS and the data exchange standard for archiving.
It has undergone extensive testing before archiving the first documents and routinely undergoes evolutions. To do this, CINES offers three separate but similar environments: one for development, another for testing, and finally the production environment where archiving is actual.
Operation of exchanges between CINES and producer / data submission service
Before any transfer, the representative of submission service will contact PAC service at CINES to develop a transfer protocol which will define the components of the archive project: identifying information to perpetuate, volume and format chosen, compliance with legal and safety standards details of the communicability, submission details, training of submission service team to use the PAC system, etc..
More details on the project progress on the archive project at CINES.
Transfert
The submission service transmits on network (via SFTP), or on removable media, the information to submit at the CINES PAC department. This information is presented the form of a SIP (submission information package ) in a submission directory structured as follows:
- the sip.xml, a metadata file describing the object to archive;
- a DEPOT directory , which contains the object to archive and may be business metadata;
- Various files that make up the object to archive;
- a DESC directory that contains the business metadata files ;
- Various business metadata files ..
The transfer is detected by applying PAC which will undertake a series of technical validity checks of data transferred:formats compliance , submissions structure… If the control is positive, the submission is transferred to the storage server where it is archived. An archive certificate is returned by the PAC service to submission service . the archive certificate contains the identifier, perenne and unique, of transferred archive and its metadata. The archive identifier is a unique identifier that allows the submission service or PAC users to find an archive
Otherwise, an error notification is sent to the submission service so that it changes the non-compliant items and returns the package archive.
Storage
any document to be archived when it reaches the storage server is copied simultaneously on two separate disks, and is backed up daily on two tapes. One of these tape is stored on a remote site. A study is also underway on the possibility of data cross-replication with the BnF: the treated archives at CINES would be on a more distant site than that currently used. This would reduce even more the risk of data loss in case of major disasters (terrorist attacks, floods, fires …).
To facilitate research, metadata associated with the document are collected and integrated into a database.
There is no suppression of documents archived in the platform. The updates are possible and are superimposed on the documents already archived.
The technology watch on developments of the storage environment, technology and developments formats is performed by the CINES. During the life of the document in the PAC system, current operating activities can be conducted (media control, migration support medium, restorations, control metadata). The producer service or the data submission service will not be informed. However, when the changes affect the format or the update metadata, the producer (or in default , the data submission service) is notified. The PAC service , for the moment, does not provide destruction functions, the archived funds considered as national interest should be retained indefinitely.
Communication
The communication is via the access server in accordance with the OAIS model and the standard exchange of data for archive.
We ensure first that the user has access rights to the platform before to provide catalog of archives to which it has access. He then makes a request for archives which, after verification of communicability, is granted or not. If the archive is not communicable, the user has the option to request, via the CINES, a derogation from the data submission service / producer.
If the communication is permitted, the access server asks storage server for archives. he prepares them and makes them available to the user in a dedicated directory.
Implémented fonctionnalities
Implémented fonctionnalities are
Transfer(Ingest) | SIP réception | Detection of a new transfer Sending of an acknowledgment |
SIP Control | Compliance sip.xml metadata against the schema sip.xsd Correspondence between the sip.xml description and files that compose the document Control and Validation of file format Calculating the hash of each file Ingestion of any representation information |
|
AIP Création | Création de l’identifiant du document archivé Mise à jour des métadonnées : sip.xml -> aip.xml Transfert de l’AIP au serveur de stockage |
|
Storage | Archiving AIP | Multiple reproduction of the AIP on different media or media sending of certificate archiving |
Administrative Tools, and maintenance of archived documents | Logging of events (time-stamped, historiated, traceable) Periodic verification of the archived AIP integrity Physical migration(change of media) Logic migration(format conversion) Provision of statements and statistics |
|
Acces | Authentification | Authentication control of the user |
---|---|---|
Request | Viewing the catalog of AIP archived Providing search results Visualization of metadata of document |
|
Communication request | Detection of a communication request Check the communicability of the document Preparation of package information to be communicate Providing a copy of the archived |
|
Request for Access derogation |