In Crypto＇05, Boneh et al. presented two broadcast encryption schemes. Their work has exciting achievements： the header （also called ciphertexts） and the private keys are of constant size. In their paper, they giv...In Crypto＇05, Boneh et al. presented two broadcast encryption schemes. Their work has exciting achievements： the header （also called ciphertexts） and the private keys are of constant size. In their paper, they give an open question to construct a traitor tracing algorithm for their broadcast encryption schemes, and combine the two systems to obtain an efficient trace-and-revoke system. In this paper, we give a negative answer to their open question. More precisely, we show that three or more insider users are able to collude to forge a valid private key for pirate decoding against their schemes. Moreover, we prove that there exists no traitor tracing algorithm to identify the colluders. Our pirate decoding can also similarly be applied to Lee et al.＇s broadcast encryption schemes in ISPEC＇06.展开更多
王飞仙所著Pirates and Publishers(中译本题为《版权谁有?翻印必究?——近代中国作者、书商与国家的版权角力战》)从多个层面论述版权和知识产权在中国发生、发展的历程,是一部系统全面的中国版权史论著,但该书也存在一些问题。本文试...王飞仙所著Pirates and Publishers(中译本题为《版权谁有?翻印必究?——近代中国作者、书商与国家的版权角力战》)从多个层面论述版权和知识产权在中国发生、发展的历程,是一部系统全面的中国版权史论著,但该书也存在一些问题。本文试图在更大范围内对晚清出版业秉持的版权观念进行全面分析,并对书中错误结论的由来展开细致讨论,深入考察中国近代书业的版权保护实践。展开更多
基金the National Natural Science Foundation of China (Grant Nos. 60303026, 60573030, and 60673077)
文摘In Crypto＇05, Boneh et al. presented two broadcast encryption schemes. Their work has exciting achievements： the header （also called ciphertexts） and the private keys are of constant size. In their paper, they give an open question to construct a traitor tracing algorithm for their broadcast encryption schemes, and combine the two systems to obtain an efficient trace-and-revoke system. In this paper, we give a negative answer to their open question. More precisely, we show that three or more insider users are able to collude to forge a valid private key for pirate decoding against their schemes. Moreover, we prove that there exists no traitor tracing algorithm to identify the colluders. Our pirate decoding can also similarly be applied to Lee et al.＇s broadcast encryption schemes in ISPEC＇06.
文摘王飞仙所著Pirates and Publishers(中译本题为《版权谁有?翻印必究?——近代中国作者、书商与国家的版权角力战》)从多个层面论述版权和知识产权在中国发生、发展的历程,是一部系统全面的中国版权史论著,但该书也存在一些问题。本文试图在更大范围内对晚清出版业秉持的版权观念进行全面分析,并对书中错误结论的由来展开细致讨论,深入考察中国近代书业的版权保护实践。
