PLEDGE Project Wiki
Welcome to the PLEDGE project, a collaboration between the MIT and UCSD Libraries and the San Diego Supercomputer Center. With funding from the National Archives and Records Administration we are conducting research and advanced development on prototypes for scalable, interoperable digital archives and preservation environments, working primarily with the DSpace digital repository platform and the SRB data grid middleware. The project proposal can be downloaded here media:PLEDGE proposal 2005.pdf
Articles and Presentations
- An article submitted to the UK Digital Curation Centre conference in Glasgow, UK (November 2006)
- An article about PLEDGE for the JCDL 2006 conference explains the major concepts of the project and how it relates to other activities in the policy arena for repositories and archives
Digital Preservation Policies
The current list of digital repository policies is here, in Word and PDF formats,
A comparison of this list with the new TRAC:Criteria and Checklist:
This comparison identifies those TRAC Criteria in the new list that are not currently in the PLEDGE list and those policies that the PLEDGE project has identified that are not included in the TRAC Criteria.
Older versions of these documents are available at: DraftPolicyDocuments
Sample DSpace Policy Definitions and Metadata
DSpace Policies are defined in order to explore the implementation of policy encoding, their enforcement in DSpace systems and their incorporation into sample DSpace AIPs.
Nine policies have been identified as pertaining to the federation and storage relationship between DSpace and iRods. These policies have been defined below and encoded as REI metadata that is included in a DSpace AIP transfered from DSpace to iRods.
DSpace Policy Definition Process Documentation
The process that was developed to define policies for DSpace has been analyzed and documented as a result of this research.
Sample DSpace Policy Metadata
This a sample encoding of the DSpace replication policy in n3 and rdf formats.
DSpace AIPs with Policy Metadata
Former versions of the DSpace policy defintions, encodings and AIPs can be found at PolicyExpressions.
Translating Policy Metadata to iRods Rules Language
Policies encoded in the REI Policy Expression Language must be translated into iRods rules language to be enforced by the iRods rules engine. A sample translation has been attempted for the policy TI0011 Replication. The policy metadata and rules declarations are included here along with analysis of the translation process.
PLEDGE Policy Metadata
iRods Rule Declaration
Policy Expression Languages
The chosen Policy Expression Language is
- Rei policy language (L. Kagal) http://www.cs.umbc.edu/~lkagal1/rei/
Other candidate Policy Expression Languages we reviewed were
- RuleML http://www.ruleml.org/
- PONDER Ponder: A Policy Language for Distributed Systems Management http://www-dse.doc.ic.ac.uk/Research/policies/ponder.shtml
- PROPEL Privacy Rights, Obligations and Permissions Exchange Language
- KAoS Policy Ontologies (KPO) http://www.ihmc.us/research/projects/KAoS/
- <indecs> Included in MPEG21 standard, DOI http://www.indecs.org/
- XACML http://xml.coverpages.org/xacml.html
- SAML http://xml.coverpages.org/saml.html
- Creative Commons use licenses http://creativecommons.org
- BPEL Business Process Execution Language http://en.wikipedia.org/wiki/BPEL
- WS-Policy Web Services Policy Framework http://www-128.ibm.com/developerworks/webservices/library/ws-polfram/summary.html
DSpace History System Analysis
- A description of the new DSpace History system is at
- A description of the new DSpace event mechanism and prototype implementation notes is at
Metadata Crosswalks for VDC Integration
In the second year of this project we are working to incorporate the Virtual Data Center into PLEDGE activities. This integration involved transforming descriptive and administrative metadata out of DDI formats and into MODS and PREMIS for inclusion in METS SIPs. Information about metadata work for the VDC Integration is available here: VDCIntegration
A list of background readings and related works is here: RelatedWork
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For more information contact MacKenzie Smith, Associate Director for Technology, MIT Libraries (kenzie at mit.edu)