A Review on Fragmentation, Allocation and Replication in Distributed Database Systems

Continuous efforts on the improvement of existing techniques of data distribution methods were shared by researchers' time-to-time. The purpose behind is to work for an effective distributed working environment to shape out the distributed system to handle vast data, continuous network expansion, and its numerous users. To satisfy database queries in distributed system users generally initiate, execute and complete his request on his node or from adjoining nodes. Here, focus is on maximize the local data processing and minimize the communication cost between sites. Optimality of results can be achieved by proper partitioning of database into disjoint sets called fragments, placement of fragment into network sites by allocation, and replication to maintain data availability and control fault tolerance. So, there is a need to calibrate large distributed system to satisfy daily data pattern of users. This research paper highlights all the antecedent techniques, algorithms, methods, design framework etc. used for the designing of data fragments, allocation and replication in distributed system.