Research On Traitor Tracing Based On Broadcast Encryption And Its Application

With the rapid development of computers and networks, the distribution of digital contents on the Internet is easier and the spread of piracy has become increasingly serious. How to protect copyright of digital contents is nowadays a critical issue. The research on traitor tracing has important theoretical and applied value for digital contents copyright protection.(1) We summarize the existing traitor tracing schemes. Threshold traitor tracing scheme, dynamic traitor tracing scheme, self-enforcement traitor tracing scheme and anonymous traitor tracing scheme are detailed introduced. Besides, the merits and demerits of these schemes are also analyzed in this paper.(2) Based on previous traitor tracing schemes, an improved digital copyright protection model is proposed which applied Oblivious Polynomial Evaluation (OPE) protocol. The users are allowed to download software freely while the merchants are permitted to generate electronic license in advance. Moreover, the scheme increases some other functions, such as revocation, non-repudiation, full frameproof and buyers'anonymity and so forth. A trusted center (TC) which protects the merchant's and the buyers'interest is introduced to the model which makes the scheme practical.(3) Aiming at the defects of Kim scheme, this paper designs an improved pay-TV management scheme for multiple channels. Firstly, this scheme uses OPE protocol on the user registration phase which makes the distribution asymmetric between the providers and users. Therefore, the scheme protects the users'decryption keys. Secondly, the new scheme modifies the original proposal in the user's channel key generation algorithm which efficiently solves the problem of two users accessing to all channels keys. Furthermore, the scheme provides the function of channel revocation which can be easily done as well as re-subscription. The scheme makes the pay-TV system truly multiply channels.