METHOD AND APPARATUS FOR BLOCKING SPAM DATA, AND METHOD AND APPARATUS FOR TRANSMITTING DATA FOR BLOCKING SPAM DATA

摘要

A method of blocking spam data is provided. The method includes: receiving a digital content file and key data, in which a key, including information for identifying a transmitter, and an electronic signature for the key are inserted as a watermark; and based on the key and the electronic signature for the key inserted in the received key data, selectively blocking the digital content file received with the key data.