Data Object Type

Definition


A set of characteristics describing a Data Object (such as the size of this object and the description of its content). Typically there will be multiple Data Objects conforming to the same Data Object Type.

Source: Producer-Archive Interface Specification (PAIS). Recommendation for Space Data System Standards, CCSDS 651.1-B-1. Blue Book. Issue 1. Washington, D.C.: CCSDS, February 2014. [Equivalent to ISO 20104:2015]

Introduction


Submission Information Packages (SIPs) include one or more Transfer Objects. A Transfer Object is a set of one or more Transfer Object Groups containing at least one Data Object that are to be transferred to the Archive.

PAIS 2.2 explains that:

One of the objectives of the Formal Definition Phase is to define the Data Objects, where hereafter a Data Object is understood to be one or more data files, to be transferred as possibly more complex data structures called Transfer Objects. Each Transfer Object is an instance of a particular Transfer Object Type. Each Transfer Object Type is described in detail by a Transfer Object Type Descriptor. A Transfer Object Type Descriptor consists of a set of mandatory, optional, and possibly user-defined attributes, and is generated for each type of Transfer Object.

Open Archival Information System (OAIS)


OAIS models information around the principle that "data interpreted using its representation information yields information."

 

Obtaining information from data. Consultative Committee on Space Data Systems. Open Archival Information System (OAIS) recommended practice, Figure 2-2. CCSDS 650.0-M-2.

This principle enables libraries, archives, and museums to apply one conceptual data model to physical objects and digital objects.

Types of Data Objects


Data Objects can be organized into two broad classes: physical and digital. Physical objects can include analog formats or digital storage devices. The Technology Watch wiki provides detailed information on the many types of data objects found in the Archives Permanent Collection.

Each type of data object is uniquely identified with a unique dataObjectTypeID (PAIS 4.2.7).

Relationship to Descriptor Models


Section 3.2.2.5 of the Producer-Archive Interface Specification (PAIS) models Transfer Object Group Types. Each type of Transfer Object Group can have one or more types of data objects.