Filling Out the Identification Area Class
The Identification_Area class is required in all PDS4 labels. It contains the unique logical identifier (LID) for the product, its version identifier (VID), a title, and a link to the PDS4 Information Model version of the master schema used to create or verify the label. It can optionally contain a modification history, and additional information used to cite the product or for cataloging in a database like the Astrophysics Data System.
For additional explanation, see the PDS4 Standards Reference, or contact your PDS node consultant.
Following are the attributes and subclasses you'll find in the Identification_Area, in label order.
Contents
<Identification_Area>
In the PDS4 master schema, all classes have capitalized names, attributes never do.
<logical_identifier>
REQUIRED
Abbreviated "LID", this identifier is unique to the product. All LIDs consist of a series of colon-separated segments. The complete rules for formulating LIDs are in the Standards Reference. Here's a brief summary:
urn:nasa:pds:{BundleID}:[{CollectionID}:[{ProductID}]]
If you're formulating the LID for a bundle, you stop at BundleID, which has to be unique across the PDS. If you're formulating a collection LID, you'll need the LID of the bundle containing this collection, to which you will add a CollectionID that is unique within the bundle. And if you're working on a product that will be part of a collection, you'll need the LID of the collection, to which you will add a ProductID that is unique within the collection.
<version_id>
REQUIRED
Abbreviated "VID", this is a version number in the form "M.m", where M and m are integers representing the major and minor revision levels, respectively. The first version delivered for archiving must be "1.0".
<title>
REQUIRED
This is a display title (or name) for the product. It should be user-friendly, in that it should help a users quickly distinguish between similar products in a search returns list. Valid characters are any UTF-8 printable characters; formatting is not preserved; 255 bytes maximum.
<information_model_version>
REQUIRED
This must be identical to the value of the version= attribute in the <xs:schema> element near the top of the PDS4 master schema. (Do not include the double quotes in the value). As things currently stand, attempting to validate a label against any other version of the master schema other than the one cited in this attribute, whether it's an earlier or later release, is a fatal error.
<product_class>
REQUIRED
The value for this must be identical to the name of the root document element of the label. In other words, if you're working on a label for an observational data product, then this attribute must have the value "Product_Observational". Case and underscores must be exact; do not include any quotes around the value.
<Alias_List>
OPTIONAL
This class is used to map the PDS4 LID to an ID in some other system (internal or external). In general, this class will be needed only rarely. It contains the following attributes:
<alternate_id>
OPTIONAL
The identifier in the other system
<alternate_title>
OPTIONAL
The title in the other system
<comment>
OPTIONAL
An explanatory comment about the system, identifier, or relationship
<Citation_Information>
OPTIONAL
This class contains authorship and publication information for the product for use in citing the product and its contents, and also for registering the product with external catalog databases like the Astrophysics Data System.
<author_list> / <editor_list>
AT LEAST ONE of author_list or editor_list must occur. BOTH may occur.
In general, the author_list credits the people responsible for collecting the data and putting it in its present object-file form with the label; the editor_list credits the people responsible for gathering existing data or documents into a PDS4 product. In either case, formatting follows the ADS conventions with the principal author/editor coming first. The format for a single name is "surname [suffix], initials", with each initial followed by a full stop ('.') and an optional space between initials. Multiple names are separated by a semi-colon (';').
<publication_year>
REQUIRED
The publication year will generally be the year that PDS released the product for public consumption. For documents, this should be the year of publication of the PDS4-labelled product, which is likely to be different from the year of publication of a document previously released in some other form (the document label contains that information elsewhere).
<description>
REQUIRED
This should be a brief description - an abstract for a document, or the equivalent for an observational, collection or bundle product.
<keyword>
OPTIONAL
The content format and constraints on this attribute is as yet undescribed, and the current definition seems incomplete. Its use should be avoided until it is adequately described.
