An accountable authority attribute-based encryption (A-ABE) scheme is presented in this paper. The notion of accountable authority identity-based encryption (A-IBE) was first introduced by Goyal at Crypto'07. It ...An accountable authority attribute-based encryption (A-ABE) scheme is presented in this paper. The notion of accountable authority identity-based encryption (A-IBE) was first introduced by Goyal at Crypto'07. It is a novel approach to mitigate the (inherent) key escrow problem in identity-based cryptosystems. In this work, the concept of accountable authority to attribute-based encryption (ABE) setting is generalized for the first time, and then a construction is given. The scheme non-trivially integrates an A-IBE scheme proposed by Libert et al. with an ABE scheme. In our construction, a user will be identified by a pair ( id, o~), where id denotes the user' s identity and ω denotes the set of attributes associated to the user. In addition, our construction is shown to be secure under some reasonable assumptions.展开更多
基金Supported by the National Natural Science Foundation of China(No.60970111,60903189,60903020)the National High Technology Research and Development Programme of China(No.2009AA012418)+1 种基金the National Basic Research Program of China(No.2007CB311201)the Foundation of NLMC(No.9140C1103020803)
文摘An accountable authority attribute-based encryption (A-ABE) scheme is presented in this paper. The notion of accountable authority identity-based encryption (A-IBE) was first introduced by Goyal at Crypto'07. It is a novel approach to mitigate the (inherent) key escrow problem in identity-based cryptosystems. In this work, the concept of accountable authority to attribute-based encryption (ABE) setting is generalized for the first time, and then a construction is given. The scheme non-trivially integrates an A-IBE scheme proposed by Libert et al. with an ABE scheme. In our construction, a user will be identified by a pair ( id, o~), where id denotes the user' s identity and ω denotes the set of attributes associated to the user. In addition, our construction is shown to be secure under some reasonable assumptions.