Search Interoperability, OAI, and Metadata: Handout for METRO Workshop

Handout for the workshop on the OAI Protocol for Metadata Harvesting given for METRO on December 8, 2006

Digitometric Services for Open Archives Environments

We describe “digitometric” services and tools that add value to open-access eprint archives using the Open Archives Initiative (OAI) Protocol for Metadata Harvesting. Celestial is an OAI cache and gateway tool. Citebase Search enhances OAI-harvested metadata with linked references harvested from the full-text to provide a web service for citation navigation and research impact analysis. Digitometrics builds on data harvested using OAI to provide advanced visualisation and hypertext navigation for the research community. Together these services provide a modular, distributed architecture for building a “semantic web” for the research literature

Beyond Harvesting: Digital Library Components as OAI Extensions

Reusability always has been a controversial topic in Digital Library (DL) design. While componentization has gained momentum in software engineering in general, there has not yet been broad DL standardization in component interfaces. Recently, the Open Archives Initiative (OAI) has begun to address this by creating a standard protocol for accessing metadata archives. It is proposed that this protocol be extended to act as the glue that binds together various components of a typical DL. In order to test the feasibility of this approach, a set of protocol extensions was created, implemented, and integrated as components of production and research DLs. The performance of these components was analyzed from the perspective of execution speed, network traffic, and data consistency. On the whole, this work has simultaneously revealed the feasibility of such OAI extensions for component interaction, and has identified aspects of the OAI protocol that constrain such extensions

BlogForever D3.2: Interoperability Prospects

This report evaluates the interoperability prospects of the BlogForever platform. Therefore, existing interoperability models are reviewed, a Delphi study to identify crucial aspects for the interoperability of web archives and digital libraries is conducted, technical interoperability standards and protocols are reviewed regarding their relevance for BlogForever, a simple approach to consider interoperability in specific usage scenarios is proposed, and a tangible approach to develop a succession plan that would allow a reliable transfer of content from the current digital archive to other digital repositories is presented

Federating Heterogeneous Digital Libraries by Metadata Harvesting

This dissertation studies the challenges and issues faced in federating heterogeneous digital libraries (DLs) by metadata harvesting. The objective of federation is to provide high-level services (e.g. transparent search across all DLs) on the collective metadata from different digital libraries. There are two main approaches to federate DLs: distributed searching approach and harvesting approach. As the distributed searching approach replies on executing queries to digital libraries in real time, it has problems with scalability. The difficulty of creating a distributed searching service for a large federation is the motivation behind Open Archives Initiatives Protocols for Metadata Harvesting (OAI-PMH). OAI-PMH supports both data providers (repositories, archives) and service providers. Service providers develop value-added services based on the information collected from data providers. Data providers are simply collections of harvestable metadata. This dissertation examines the application of the metadata harvesting approach in DL federations. It addresses the following problems: (1) Whether or not metadata harvesting provides a realistic and scalable solution for DL federation. (2) What is the status of and problems with current data provider implementations, and how to solve these problems. (3) How to synchronize data providers and service providers. (4) How to build different types of federation services over harvested metadata. (5) How to create a scalable and reliable infrastructure to support federation services. The work done in this dissertation is based on OAI-PMH, and the results have influenced the evolution of OAI-PMH. However, the results are not limited to the scope of OAI-PMH. Our approach is to design and build key services for metadata harvesting and to deploy them on the Web. Implementing a publicly available service allows us to demonstrate how these approaches are practical. The problems posed above are evaluated by performing experiments over these services. To summarize the results of this thesis, we conclude that the metadata harvesting approach is a realistic and scalable approach to federate heterogeneous DLs. We present two models of building federation services: a centralized model and a replicated model. Our experiments also demonstrate that the repository synchronization problem can be addressed by push, pull, and hybrid push/pull models; each model has its strengths and weaknesses and fits a specific scenario. Finally, we present a scalable and reliable infrastructure to support the applications of metadata harvesting

Developing IPR solutions for academic author self-archiving

This paper describes the work of the UK JISC-funded RoMEO (Rights Metadata for open archiving) project. It reports on a survey of 542 academic authors and an analysis of 80 journal publishers’ copyright transfer agreements, and how they have informed the development of some simple rights metadata by which academics can protect their research papers in an open access environment. It also reports on a survey of 22 OAI Data Providers and 13 OAI Service Providers, and how the results have informed the development of a “metadata protection solution” that describes the conditions of use of freely available metadata

Using Timed-Release Cryptography to Mitigate Preservation Risk of Embargo Periods

This research defines Time-Locked Embargo, a framework designed to mitigate the Preservation Risk Interval: the preservation risk associated with embargoed scholarly material. Due to temporary access restrictions, embargoed data cannot be distributed freely and thus preserved via data refreshing during the embargo time interval. A solution to mitigate the risk of data loss has been developed by suggesting a data dissemination framework that allows data refreshing of encrypted instances of embargoed content in an open, unrestricted scholarly community. This framework has been developed by exploiting implementations of existing technologies to time-lock data using Timed-Release Cryptology (TRC) so that it can be deployed s digital resources encoded in the MPEG-21 Digital Item Description Language (DIDL) complex object format to harvesters interested in harvesting a local copy of content by utilizing The Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH), a widely accepted interoperability standard for the exchange of metadata. The framework successfully demonstrates dynamic record identification, time-lock puzzle (TLP) encryption, encapsulation and dissemination as XML documents. This thesis dissertation presents the framework architecture and provides a quantitative analysis of an implementation. The framework demonstrates successful data harvest of time-locked embargoed data with minimum time overhead without compromising data security and integrity

The CARL metadata harvester and search service

This paper documents the use of unqualified Dublin Core (uDC) elements in the metadata harvested from the repositories participating in the CARL harvester, and identifies patterns in the use of that metadata. It also compares these findings with a similar study, and identifies areas for further research