Replication on geographically distributed, unreliable, P2P interconnecting nodes can offer high data availability and low network latency for replica access. The challenge is how to take good control of the number of replicas and their distribution over well-chosen nodes to get a good replica access performance. We observe that, there exists such a logical node cluster overlay over any P2P data-store’s underlying network topology that the replica transmission delay of inter-cluster is much greater than that of intra-cluster because of geographical distance or bandwidth sharing between nodes in different clusters. Based on nodes-clustering, we propose a decentralized algorithm ACB-R to direct the data replication, which can adapt dynamically to the changing replica access patterns or network topologies. The experiment shows that ACB-R can benefit much of the access requests at the price of negligible intra-cluster replica transmission and consequently achieves a good average replic...