\input zb-basic \input zb-ioport \iteman{io-port 05542158} \itemau{Del-Fabbro, Bruno; Laiymani, David; Nicod, Jean-Marc; Philippe, Laurent} \itemti{DTM: a service for managing data persistency and data replication in network-enabled server environments.} \itemso{Concurrency Comput. Pract. Exp. 19, No. 16, 2125-2140 (2007).} \itemab Summary: Network-enabled server (NES) environments are valuable candidates to provide simple computing Grid access. These environments allow transparent access to a set of computational servers via Remote Procedure Call mechanisms. In this context, a challenge is to increase performances by decreasing data traffic. This paper presents DTM (Data Tree Manager), a data management service for NES environments. Based on the notions of data persistency and data replication, DTM proposes a set of efficient policies which minimize computation times by decreasing data transfers between the clients and the platform. From the end-user point of view, DTM is accessible through a simple and transparent API. We describe DTM and its implementation in the DIET (Distributed Interactive Engineering Toolbox) platform. We also present a set of experimental results which show the feasibility and the efficiency of our approach. \itemrv{~} \itemcc{} \itemut{grid computing; data management; persistency; replication; DIET} \itemli{doi:10.1002/cpe.1185} \end