Abstract: A method for using digital contents is provided. In the method, a request is made to a provider apparatus for a certificate containing a first provider ID embedded therein by a certification authority, and the certificate is received from the provider apparatus. A decision is made by using the certificate as to whether or not the provider is authorized by the certification authority. A request is made to the provider apparatus for a digital content having a second provider ID embedded therein by a contents guarantee authority when the provider is authorized by the certification authority, and the digital content is received from the provider. The first provider ID is read from the certificate, the digital content is correlated with the second provider ID, and the digital content is stored in a storage medium. The second provider ID is detected from the digital content in response to a request to use the digital content.

Abstract: A method for using digital contents is provided. In the method, a request is made to a provider apparatus for a certificate containing a first provider ID embedded therein by a certification authority, and the certificate is received from the provider apparatus. A decision is made by using the certificate as to whether or not the provider is authorized by the certification authority. A request is made to the provider apparatus for a digital content having a second provider ID embedded therein by a contents guarantee authority when the provider is authorized by the certification authority, and the digital content is received from the provider. The first provider ID is read from the certificate, the digital content is correlated with the second provider ID, and the digital content is stored in a storage medium. The second provider ID is detected from the digital content in response to a request to use the digital content.

Abstract: A system for distributing broadcast contents, in which the copyright of the broadcast contents can be protected, is provided. The system is a watermarking application system for broadcast contents copyright protection, constituted by a broadcasting station of broadcast contents, a broadcasting receiver of the broadcast contents, a network monitoring agent for monitoring secondary contents of the broadcast contents, a secondary content player for playing secondary contents, communication receivers for recognizing distribution of secondary contents, etc. Pieces of digital watermarking embedding equipment are provided in the broadcasting station and the broadcasting receiver respectively. Pieces of digital watermarking extraction equipment are provided in the network monitoring agent and the secondary content player. Particularly, the broadcast contents are outputted through an analog output or an internal disk.

Abstract: For providing a device for serving search/report to viewers responding to an inquiry from the viewers, about information relating to EPGs of the BS digital broadcasting and contents of the data broadcasting services, all channels of the EPGs information of the BS digital broadcasting and the content information of the data broadcasting are received, so as to establish a data base thereof, and at the same time a key-word search data base is also established, thereby supplying a EPG service and a search service, etc., responding to a request for information supply from the viewer.