iPRES 2010 - Tutorial: Stability of digital resources on the Internet and strategies for persistent identifier

Within research activity worldwide about digital preservation many studies, criteria sets, tools, strategies, standards and best practices have been developed by the practitioners: one of these technology families is the Persistent Identifier (PI) to grant stability of digital objects over time. PIs give things that we use or talk about in information systems a unique and stable name. While the location of a resource may change, its PI remains the same. Persistent identification of Internet resources is a crucial issue for almost all the sectors of the future information society. In particular, in the cultural/scientific digital library applications, the instability of URLs reduces the credibility of digital resources which is a serious drawback especially for researchers.

There are various concepts and schemes for persistent identification that pretend to solve this problem: Digital Object Identifier (DOI), Persistent Uniform Resource Locator (PURL), Archival Resource Key (ARK) and Uniform Resource Name (URN) to name a few. They all share common goals but there are indeed important differences between these approaches with respect to the use cases, communities and business models towards they are directed. Recently the diversity of possible solutions is getting even more confusing: The PI systems mentioned above all primarily focus on the identification of web resources that are meant to be available in the long term and are subject to long-term preservation. But with the raise of the Data Web, which is driven by the success of social networks and the Linking Open Data movement, the identification of non-digital entities (like real-world objects, events, places and persons) and abstract concepts is getting more and more important. Especially in this context the traditional PI systems compete with lightweight solutions like "Cool URIs" and Hashtags.

But the key qualities of a PI service are mostly independent of the scheme it uses. They concern trust and reliability. No technology can grant a level of service in any case without a trustable organisation and clear defined policies: it is well known that digital preservation is more an organisational issue than a technical one. European activities, like the development of the Europeana Resolution Discovery Service and PersID, focus on the harmonization of the national PI strategies and embed all these existing approaches into a shared infrastructure. The aim is to establish a transparent and trusted service for the cultural and academic sector. The crucial question is: How much und what kind of regulation by public authorities does the web of culture and research need?

In this tutorial we explain the importance of trusted Persistent Identifier services for the web's evolution and present a survey of available technologies and current practices. The tutorial starts with introduction of the problems PI systems try to solve today and those that they will have to address in the future. Then we will present a survey of available technologies and the major initiatives world wide, talk about their commonalities and differences and highlight the most important issues and problems with the current situation. More in detail the Europeana Resolution Discovery Service (ERDS) and the PersID goals and plans will be outlined. The tutorial will close with an open debate or round table on "use cases and user requirements for a PI system".

The tutorial is directed towards people in charge of digital repositories, institutions working in the context of linked data, authors of digital contents, software companies developing archival solutions and digital library applications, researchers and students working on digital libraries for cultural and scientific resources.