System and method for fast and scalable multimedia authentication in real time environment

A method of processing a plurality of digital data files including at least one group of medium data files for constituting a sequence of events or activities of a time interval for secure delivery of the digital data files, the method comprising the steps of: (a) processing a plurality of digital data files so as to generate a file identification value for each digital data file, wherein the file identification value of a digital data file is an one-way arithmetic value characteristic of the data content of the digital data file; (b) processing the file identification values to generate an authentication root value, the authentication root value being an one-way arithmetic value characteristic of the plurality of file identification values; (c) encrypting the root value; and (d) grouping the encrypted authentication root value and a selected plurality of digital data files with a set of authentication information for delivery, wherein the set of authentication information is derived from the file identification values and is for deriving a test root value when in combination with said selected plurality of digital data files, and wherein the test root value is for comparison with the authentication root value to detect tampering of said selected plurality of data files.