Abstract: Disclosed is an advertisement method in a digital broadcasting for facilitating digital broadcasting and fostering efficiency of advertisement in the digital broadcasting. A designated advertisement image is provided at the appointed time with reference to time data extracted from a broadcasting stream for a broadcasting program The advertisement image is either relevant or irrelevant to the broadcasting program. Also, the advertisement image can be displayed on an A/V broadcasting screen or on a data-broadcasting screen.

Abstract: Disclosed are a data broadcasting system and an operating method thereof that can provide advertisement while a viewer receives data with a delay. A method for operating a data broadcasting system of the present invention includes the steps of: downloading a data service table for a specific application at the client; providing an advertisement and performing a data receiving process at the same time with reference to the data service table; and executing the specific application using data files extracted through the data receiving process.

Abstract: Disclosed is a file searching method of a data broadcasting system, the method including the steps of: confirming whether or not a control message of Download Server Initiate is updated, in response to a search request for a file object; and searching the search-requested file object from at a new root directory object, in case that the control message of Download Server Initiate is updated.