1. Midterm Workshop, Catania, April 2014 D3.1 State of the art assessment on Linked Data and Digital Preservation René van Horik, Data Archiving & Networked Services, The Netherlands

2. Midterm Workshop, Catania, April 2014 Outline Introduction / Context Summary of Deliverable D3.1

3. Midterm Workshop, Catania, April 2014 Objectives of the PRELIDA Project collect, organize and publish use cases related to the long-term access to LD create a comprehensive state of the art on LD and DP technologies set up a technology observatory bring together scientists and stakeholders for identifying relevant challenges and paths for addressing them in the near future draw attention of standardization bodies

4. Midterm Workshop, Catania, April 2014 WP3 of Prelida project Objective of WP3: – to provide overview of the state of art in Digital Preservation and Linked Data. – Information transfer between two communities. Partners: CNR / APA / HUD / UIBK Contributors: Sotiris Batsakis, David Giaretta, Christophe Gueret, René van Horik, Maarten Hogerwerf, Antoine Isaac, Carlo Meghini, Andrea Scharnhorst. Deliverables: – WP3.1 State of the art (month 12) – WP3.2 Consolidated state of art (month 24)

5. Midterm Workshop, Catania, April 2014 Two communities: Linked Data & Digital Preservation Plato and Aristotle. Fragment of fresco “the School of Athens” by Raphael (1509-1510) Only sensorial experience can lead to knowledge. Pointing to the earth (realism) Applied mathematical methods leads to knowledge. Pointing to heaven (mystical nature of the universe)

6. Midterm Workshop, Catania, April 2014 Table of contents of D3.1 1.Introduction 2.Definitions and terminology 3.Relevant dimensions addressed by DP projects 4.Initial ideas on preserving Linked (Open) Data 5.Use cases – Cedar – Dbpedia – Europeana 6.Conclusions 7.Bibliography

7. Midterm Workshop, Catania, April 2014 Definitions and terminology

8. Midterm Workshop, Catania, April 2014 Digital Preservation Long Term Preservation as defined by the OAIS reference model: Components: Long Term Independently Understandable Designated Community Authenticity Information Data Representation Information (see page 15)

9. Midterm Workshop, Catania, April 2014 Threats to digital preservation

10. Midterm Workshop, Catania, April 2014 The obvious slide on data

11. Midterm Workshop, Catania, April 2014 Linked (Open) Data Use the Web as a platform to publish and re-use identifiers that refer to data Use a single data model for expressing the data (RDF) 3 ways to publish RDF data: – As annotation to Web documents (RDF data included within the HTML code of the Web) – As Web documents (RDF documents are served next to HTML documents) – As a database (“triple stores”, query language: SPARQL) (see page 23 for example related to Dbpedia)

12. Midterm Workshop, Catania, April 2014 Three ways to publish RDF data

13. Midterm Workshop, Catania, April 2014 Relevant dimensions addressed by DP projects

14. Midterm Workshop, Catania, April 2014 What is specific for LOD for the DP community? A number of formats (RDF / Triple Store / …) No clear boundary Dynamic, changes over time Unclear ownership

15. Midterm Workshop, Catania, April 2014 DP topics potentially relevant for preservation of LD objects Object classification and validation Persistent identifiers Audit & Certification / Trustworthy Digital Repositories

16. Midterm Workshop, Catania, April 2014 Some initial ideas on preserving LOD Object classification Representation information -> Representation network (Persistent Identifiers) (Audit & Cetification of TDR)

17. Midterm Workshop, Catania, April 2014 Classification of objects must at least make sure we consider different types of data – rendered vs non-rendered – composite vs simple – dynamic vs static – active vs passive RDF Triple: dynamic/complex/non-rendered/passive (page 38)

18. Midterm Workshop, Catania, April 2014 OAIS Information model: Representation Information The Information Model is key Recursion ends at KNOWLEDGEBASE of the DESIGNATED COMMUNITY (this knowledge will change over time and region) Does not demand that ALL Representation Information be collected at once. A process which can be tested

19. Midterm Workshop, Catania, April 2014 Use Cases CEDAR Dbpedia Europeana

20. Midterm Workshop, Catania, April 2014

21. Thank you

22. Midterm Workshop, Catania, April 2014

23. Linked Open Data Stack http://www.timdavies.org.uk/wp- content/uploads/Diagrams- Elements-of-the-Linked-Open- Data-Puzzle-Draft-3.png

24. Midterm Workshop, Catania, April 2014 5 star deployment scheme for Open Data