H.2. Package Structures for Long Term Preservation

201. NATO digital information of permanent value shall be processed by their Information Custodians into single digital information items with associated metadata and packaged into submission and archival information package structures [6].

H.2.1. Submission Information Package

202. NATO digital information of permanent value selected by Information Custodians for long term preservation should be delivered to the NATO Archivist as a Submission Information Package (SIP).

203. The SIP consists of two parts: the actual information packaged as a single digital information item and a set of metadata associated with this item (see Figure H.2)

Submission Information Package structure
Figure H.2. Submission Information Package structure

204. The single digital information item has the following structure:

  • Content: Information of one of the seven types listed under Section H.1). For certain types of content, primarily data sets (Section H.1.1), several pieces of information might be grouped. A schema provided as part of the Data Definition can be used to describe the structure of these groupings. For other types such as documents, images, or recordings, information items shall be included individually. Items might contain other objects that should also be preserved in a sustainable format. For example, an archived email message could have text documents as attachments that should be stored in the sustainable formats listed in Section H.1.2). Guidance on granularity and grouping will be provided by the Archives Committee.

  • Data Definition: If the Content consists of structured data, a separate Data Definition shall be included that describes the logical structure of the Content. This is primarily applicable to Content of the types Data Set (Section H.1.1), Geospatial (Section H.1.6), and Web Archive (Section H.1.7). The format of the Data Definition shall be XML Schema 1.1.

  • Visualization: A visualization and human readable representation of contextual information is optional. The format used for the context information shall be one of those listed under Section H.1).

205. The individual parts (Content, Data Definition and Visualization) shall be packaged as a single digital information item by using the Open Packaging Conventions [7] format.

206. The file name of the packaged single digital information item shall follow the NATO Guidance on File Naming [5]. OPC does not define an extension; the .zip extension shall be used for packages for long term preservation.

207. The SIP or AIP shall contain a basic set of metadata for the container. OPC supports a subset of six Dublin Core metadata elements (creator, description, identifier, language, subject, and title) and two Dublin Core terms (created, modified). The elements shall be filled by the Information Custodian when the OPC container for the single digital information item is created. Note that this metadata refers to the container itself, not to its contents. For example, the creation date is the date the container was created, not the creation date of the content.

208. In addition to the OPC container metadata, the Information Custodian will generate a full metadata description for the content of the SIP, including the classification of the single digital information item.

209. The SIP metadata follows the NATO Core Metadata Specification (NCMS) [1] and the NATO Labelling Specification [3]. Values for all mandatory elements shall be assigned by the Information Custodian. The NATO Archivist shall reject all submissions with incomplete metadata.

210. No information of permanent value packaged in a SIP and submitted by the Information Custodian shall be destroyed unless the SIP has been explicitly acknowledged and accepted by the NATO Archivist.

H.2.2. Archival Information Package

211. If the content of the SIP submitted by an Information Custodian for long-term preservation are accepted by the NATO Archivist, the SIP will be processed into an Archival Information Package (AIP).

212. The AIP consists of the same structure as the SIP, i.e. the single digital information item for long-term preservation packaged as an OPC container, and the NCMS-compliant metadata information bound to the container.

213. As part of the Ingest process, the metadata supplied with the SIP will be augmented by preservation metadata approved by the NATO Archivist. In addition, NATO Archivist shall become the custodian for the AIP.

214. The preservation metadata will be an extension to the NCMS metadata. The extension shall be based on the PREMIS metadata set [8].