Exemplary embodiments may involve a meta-data server that manages data-server access control list (DS ACL) information. Each entry of this DS ACL information may include an address of a data server, an identification or a range address of chunk data on the data server, a file path of the chunk data in the file tree provided by the meta-data server, and addresses of the permitted clients. The meta-data server may determine the addresses of the permitted clients for the chunk data by retrieving the original file path of chunk data from layout information of the meta-data server, and by retrieving the entry containing the directory path that partially matches with the original file path from an access control list of the meta-data server.