Open Digital Libraries

Digital Libraries (DLs) are software systems specifically designed to assist users in information seeking activities. Stemming from the intersection of library sciences and computer networking, traditional DL systems impose library philosophies of structure and management on the sprawling collections of data that are made possible through the Internet.

DLs evolve to keep pace with innovation on the Internet so there is little standardization in the architecture of such systems. However, in attempting to provide users with the highest possible levels of service with the minimum possible effort, many systems work collaboratively with others, e.g., meta-search engines. This type of system interoperability is encouraged by the emergence of simple data transfer protocols such as the Open Archives Initiative?s Protocol for Metadata Harvesting (OAI-PMH).

Open Digital Libraries are an extension of the work of the OAI. It is proposed in this dissertation that the philosophy and approach adopted by the OAI can easily be extended to support inter-component interaction within a componentized DL. In particular, DLs can be built by connecting small components that communicate through a family of lightweight protocols, using XML as the data interchange mechanism. In order to test the feasibility of this, a set of protocols was designed based on a generalization of the work of the OAI. Components adhering to these protocols were implemented and integrated into production and research DLs. These systems were then evaluated for simplicity, reusability, and performance.

On the whole, this study has shown promise in the approach of applying the fundamental concepts of the OAI protocol to the task of DL component design and implementation. Further, it has shown the feasibility of building componentized DL systems using techniques that are a precursor to the Web Services approach to system design.