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The PREMIS Editorial Committee is pleased to announce the release of PREMIS version 2.3. Changes in this version allow users to specify an authority from which a controlled vocabulary value is taken, either in the form of a URI or a string. These changes are only to the XML schema and are not yet referenced in the PREMIS Data Dictionary for Preservation Metadata.  The authority attributes will be documented in the next revision; the Editorial Committee is working on version 3.0, which we expect will be issued around the end of this year.

Specific schema changes are:

Addition of a new complexType 'stringPlusAuthority', references new attribute group 'authorityAttributeGroup'.
'stringPlusAuthority' is xs:string with the three new attributes: 
authority: to specify the name of a controlled vocabulary (as a string) from which the value is taken that is used in the element.
authorityURI: to specify the name of a controlled vocabulary from which the value is taken in the form of a URI . 
valueURI:  to specify the value from a controlled vocabulary that is in the form of a URI.

61 elements can (optionally) take these attributes. In the PREMIS Data Dictionary the value constraint for these indicates that the value should be taken from a controlled vocabulary.  Previously they only took a string and there wasn't a mechanism to specify which controlled vocabulary was used. These are now of type 'stringPlusAuthority' instead of 'xs:string'.  They have been separated out from the list of element declarations and are listed together, under "****** stringPlusAuthority type element declarations"

In addition the two elements of type 'countryCode' (copyrightJurisdiction and statuteJurisdiction) are similarly separated out and listed together. The 'countryCode' definition is changed, to accomodate the authority attributes.  it now has a base of 'stringPlusAuthority' rather than xs:string, and it is an extension rather than
a restriction (hence a complex rather than simple type).

Following is an example of usage:

<eventIdentifier>
  <eventIdentifierType>UUID</eventIdentifierType>
  <eventIdentifierValue>908985d3-9600-4da4-a7e7-c6e9508bf24c</eventIdentifierValue>
</eventIdentifier>
<eventType authority="premisEventType" authorityURI="http://id.loc.gov/vocabulary/preservation/eventType.html" valueURI="http://id.loc.gov/vocabulary/preservation/eventType/val.html">validation</eventType>
<eventDateTime>2014-07-03T23:18:19</eventDateTime>
<eventDetail>program="Jhove"; version="1.5"</eventDetail>
<eventOutcomeInformation>
  <eventOutcome>fail</eventOutcome>
  <eventOutcomeDetail>
    <eventOutcomeDetailNote>format="JPEG"; version="1.02"; result="Not well-formed"</eventOutcomeDetailNote>
  </eventOutcomeDetail>
</eventOutcomeInformation>

Note that in the above example eventType could include any or all of the authority attributes and, if valueURI is used, it does not have to include a string value within the element.

The new schema is at:
http://www.loc.gov/standards/premis/premis.xsd
and we also keep a copy at:
http://www.loc.gov/standards/premis/v2/premis-v2-3.xsd 

A number of preservation metadata controlled vocabularies are available as Linked Data (so all concept schemes and concepts in these vocabularies have a URI):
http://id.loc.gov/vocabulary/preservation
Other elements that take the authority attributes which do not have established schemes at id.loc.gov include those for which a local value would be used.

Since this is not a major change, XML instances for version 2.2 (and previous version 2 instances) will still validate against this revised schema.  


Rebecca

Rebecca  Squire Guenther
Chair, PREMIS Editorial Committee, Library of Congress
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