抗合谋攻击是数字指纹技术中需要解决的关键问题之一.基于二进制随机编码,通过使用伪随机序列对指纹比特的重复嵌入进行控制,提出了一种有效的抗合谋攻击的数字指纹编码算法及其相应的跟踪算法.理论分析和实验结果表明,在适当的合谋尺寸下,该算法能够对非法分发者进行有效跟踪,同时无辜用户被诬陷的概率可以根据要求接近于0.由于在该算法中发行商无须知道用户原来的码字,因此可以说该算法是设计非对称指纹的一个很好的备选算法.

Digital fingerprinting has appeared as a new technique for copyright protection of digital contents. How to defense collusive attack is one of the key problems when designing fingerprinting algorithms. In this paper, based on the binary random coding methods, a fingerprinting algorithm and the corresponding tracing algorithm are proposed by using a pseudo-random sequence to control the embedding of the fingerprint bits. Both theoretical analysis and experimental results show that under reasonable collusion size, by the fingerprinting algorithm, the owner can trace the traitors quite efficiently and the probability to accuse an innocent buyer can be made as close as to 0. Furthermore, because the owner need not know the buyers?fingerprints, the method can serve as a good coding algorithm in the design of asymmetric fingerprinting schemes.

Supported by the National Grand Fundamental Research 973 Program of China under Grant No.G1999035805 (国家重点基础研究发展规划(973)); the Youth Foundation of the National High-Tech Research and Development Plan under Grant No.2001AA140447 (国家高技术研究发展计划青年基金); the Innovation Foundation of the State Key Laboratory of Information Security of Graduate School of the Chinese Academy of Sciences of China (中国科学院研究生院信息安全国家重点实验室创新基金)