: We investigate the performance and the scalability metrics of the Digital Information Service framework that is for unifying and federating online digital entities. The Digital Information Service consists of tools and services for supporting Cyberinfrastructure based scientific research. This system supports a number of existing online Web 2.0 research tools (social bookmarking, academic search, scientific databases, journal and conference content management systems) and aims to develop added-value community building tools that leverage the management and federation of digital entities and their metadata obtained from multiple services. We introduce a prototype implementation and present its evaluation. As the results indicate, the proposed system achieves federation and unification of digital entities coming from different sources with negligible processing overheads. KEY WORDS: Collaboration, Web 2.0, Annotation Tools, Distributed Annotation Records, Federation, Unification, Consi...