New channels for carrying copyright and usage rights data in digital multimedia distribution

Protection of intellectual property is a critical issue in digital multimedia distribution systems. Cryptographic tools are commonly used for secure delivery of content and access keys to consumers via terrestrial, satellite, cable and Internet transmissions. A third requirement is the distribution of the copyright or usage rights associated with the digital content. The integrity, as opposed to security, of this data is essential to prevent unauthorized modification. Two approaches have been proposed in the open literature: allocating special fields in the transport stream and embedding a watermark into multimedia content. We present two new methods, based on secret sharing, to create channels with guaranteed data integrity.