A Transparent Service Replication Mechanism for Clouds

File replication in distributed environment has been discussed by many researchers, but the issues like transparency and their impact on the overall system performance, are rarely focused, when deployed in the cloud environment. Distributed computing started with the cluster followed by the grid and is now in the era of cloud computing, where most of the services are accessed, by few clicks. In cloud, services are invoked on demand and there is no need of dedicated resources. It demands the availability of resources(i.e. logical resources), in order to fulfill the user requirements. To make this feasible, on-demand availability of logical resources (LR) is preferred. This work proposes an "OndemandLogical Resource Replication Scheme" (OLRRS) for file replication. OLRRS approach provides migration, access and performance transparency to the system, thereby ensuring the migration decisions about the files. It is also responsible for replicating the file, from one peer server to the other peer server, when the total number of request, on a peer server, for transferring a file reaches the threshold value. The scheme is simulated on JAVA platform and tested on a private cloud. A comparative study of the proposed approach with the Request Reply and Request Reply (RR) Acknowledgement (RRA)protocol is presented, showing the significant reduction by 37.5% to 58%, in terms of total number of messages exchanged for replication.