Transaction-Based Grid Database Replication

We present a framework for grid database replication. Data replication is one of the most useful strategies to achieve high levels of availability and fault tolerance as well as minimal access time in grids. It is commonly demanded by many grid applications. However, most existing grid replication systems only deal with read-only files. By contrast, several relational database vendors provide tools that offer transaction-based replication, but the capabilities of these products are insufficient to address grid issues. They lack scalability and cannot cope with the heterogeneous nature of grid resources. Our approach uses existing grid mechanisms to provide a metadata registry and to make initial replicas of data resources. We then define high-level APIs for managing transaction-based replication. These APIs can be mapped to a variety of relational database replication mechanisms allowing us to use existing vendor-specific solutions. The next stage in the project will use OGSADAI to manage replication across multiple domains. In this way, our framework can support transaction-based database synchronisation that maintains consistency in a data-intensive, largescale distributed, disparate networking environment.