版权保护中的组合安全码及相关问题

The rapid development of modern science and technology not only provides convenience for data communication, but also poses a tremendous threat to the copyright of digital content. This paper focuses on the mathematical theory of traitor-tracing for copyright protection and its latest progress. First, for applications in different scenarios, such as broadcast encryption and multimedia fingerprinting, we introduce unified models to characterize the (key/fingerprint) distribution schemes with traceability property and frameproof property, respectively. Next, we review several classes of combinatorial secure codes with the traceability property and frameproof property, and the combinatorial methods used to investigate the bounds on the maximum code size and the explicit constructions, as well as the latest results and the open problems. The relationships between the combinatorial problems in copyright protection and the related problems in group testing and multiple access communication are discussed as well.