Communication is established between a first client and a central index server in a fluid, de-centralized network. The central index server searches the memory of the first client for usable data files which lack authentication certificates issued by the central index server. A data-file identifier is generated for a first data file among the select files lacking authentication certificates within the first client. The data-file identifier is compared to a reliable identifier in a main data base of the central index server. The reliable identifier is indexed within the main data base against a first unique reference ID. If the data-file identifier matches the reliable identifier, a valid authentication certificate is issued to the first data file in the first client. An IP address of the first client is then referenced against the first unique reference ID within the main data base of the central index server. When file request is received from a second client for a file represented by the first unique reference ID, a connection is facilitated between the first client and the second client so that the authenticated first multimedia data file can be transferred from the first client to the second client. If the data-file identifier does not match the reliable identifier within the data base, no authentication certificate is issued, and the first data-file identifier is systematically compared against a remaining plurality of identifiers within the main data base of the central index server to determine its true identity.