in-Browser Digital Library Services

Service models for digital libraries have looked into how services may be decomposed into modules and components for greater flexiblity. These models are, however, mostly aimed at server-side applications. With the emergence of Ajax and similar techniques for processing XML documents within a Web browser, it has now become feasible for a browser to perform far more of the computational tasks traditionally encompassed in server-side DL services. Among other advantages, moving computation to the client can result in improved performance and scalability. As a new twist on service oriented computing, it is argued in this paper that digital library services can be provided partially or wholly through applications that execute client-side. Two case studies are provided to illustrate that such in-browser services are feasible and in fact more powerful and flexible than the traditional server-side service model

Utility-based high performance digital library systems

Many practical digital library systems have had to deal with scalability of data collections and/or service provision. Early attempts at enabling this scalability focused on data/services closely coupled with or tightly integrated with various high performance computing platforms. This inevitably resulted in compromises and very specific solutions. This paper presents an analysis of current high performance systems and motivates for why utility computing can subsume existing models and better meet the needs of generic scalable digital library systems

Hybrid Online-Offline Digital Collections

Online digital repositories are rapidly becoming the norm to store various different forms of content, including academic documents and heritage collections. There are many advantages to online systems, including general accessibility and the increasing use of Web browsers as a platform. However, it can argued that, for the preservation of heritage, offline systems may offer other advantages, such as replication, simplicity and cost-effectiveness. This paper describes an attempt to exploit advantages of both approaches in the form of a combined online-offline digital repository, where some content is online on a Web server and other content is offline on a DVD-ROM. This new approach to designing systems for preservation and access is especially useful in areas with limited Internet bandwidth, such as in most African countries. Experimental results confirm that this system is effective and efficient

Cloud Computing for Digital Libraries

Information management systems (digital libraries/repositories, learning management systems, content management systems) provide key technologies for the storage, preservation and dissemination of knowledge in its various forms, such as research documents, theses and dissertations, cultural heritage documents and audio files. These systems can make use of cloud computing to achieve high levels of scalability, while making services accessible to all at reasonable infrastructure costs and on-demand. This research aims to develop techniques for building scalable digital information management systems based on efficient and on-demand use of generic grid-based technologies such as cloud computing. In particular, this study explores the use of existing cloud computing resources offered by some popular cloud computing vendors such as Amazon Web Services. This involves making use of Amazon Simple Storage Service (Amazon S3) to store large and increasing volumes of data, Amazon Elastic Compute Cloud (Amazon EC2) to provide the required computational power and Amazon SimpleDB for querying and data indexing on Amazon S3. A proof-of-concept application comprising typical digital library services was developed and deployed in the cloud environment and evaluated for scalability when the demand for more data and services increases. The results from the evaluation show that it is possible to adopt cloud computing for digital libraries in addressing issues of massive data handling and dealing with large numbers of concurrent requests. Existing digital library systems could be migrated and deployed into the cloud