Hybrid consistency framework for distributed annotation records in a collaborative environment

We describe a novel hybrid consistency framework that supports collaboration and maintains consistency among distributed annotation records, which are replicas of the same document, kept at various Web-based annotation tools. There are issues in semantics of annotation tools. Each annotation tool stores different and limited metadata, has different rules for tags, and does not provide timing information for the updated records. As a result of these, the same documents can be updated inconsistently with unknown precise timestamps and spread around in existing annotation tools with different versions. Moreover, communication of annotation tools with each other is also very limited through various forms and this also contributes to inconsistencies among distributed annotation records. To deal with these major shortcomings, this paper introduces the notion of "hybrid-consistency framework", which allows collaboration on shared records and maintains the consistency among distributed annotation records held at various annotation tools, through pull and push based consistency mechanism. We discuss the overall design, architecture and the components of the hybrid consistency framework, and provide a working prototype implementation and a roadmap of the future work in this research.