A method of constructing and handling requests for data files

摘要

A digital broadcast system comprises a receiving means, a selecting means and an output means. The receiving means receives a trigger signal 92 signifying that broadcast of a current segment of media information has commenced via a digital broadcasting channel. The trigger signal comprises a media information identifier which identifies the current segment of media information. The selecting means selects a data file relating to the current segment identified by the media information identifier. The output means outputs the related data file to the digital broadcasting channel for broadcast with the current segment of the media information. The output means is arranged to control the timing of the output of the related data file such that the data file is output as a consequence of receipt of the trigger signal.