Identity-based proxy signature enables an entity to delegate its signing rights to another entity in identity-based cryptosystem settings. However, few existing scheme has been proved secure in a formalized model, or ...Identity-based proxy signature enables an entity to delegate its signing rights to another entity in identity-based cryptosystem settings. However, few existing scheme has been proved secure in a formalized model, or acquired optimized performance. To achieve the goals of both proven security and high efficiency, this paper proposed an efficient identity-based proxy signature scheme. The scheme is constructed from bilinear pairing and proved secure in the random oracle model, using the oracle replay attack technique introduced by Pointehval and Stern. The analysis shows that the scheme needs less computation costs and has a shorter signature than the other schemes.展开更多
Key escrow is an inherent disadvantage for traditional ID-based cryptosystem, i.e., the dishonest private key generator (PKG) can forge the signature of any user, meanwhile, the user can deny the signature actually si...Key escrow is an inherent disadvantage for traditional ID-based cryptosystem, i.e., the dishonest private key generator (PKG) can forge the signature of any user, meanwhile, the user can deny the signature actually signed by him/herself. To avoid the keyescrow problem, an ID-based signature scheme was presented without trusted PKG. The exact proof of security was presented to demonstrate that our scheme is secure against existential forgery on adaptively chosen message and ID attacks assuming the complexity of computational Diffie-Hellman (CDH) problem. Compared with other signature schemes, the proposed scheme is more efficient.展开更多
基金National Natural Science Foundation of Chi-na for Distinguished Young Scholars (No.60225007)National Research Fund for theDoctoral Program of Higher Education ofChina (No.20020248024)Grant-in-Aid forScientific Research(C) (No.14540100)
文摘Identity-based proxy signature enables an entity to delegate its signing rights to another entity in identity-based cryptosystem settings. However, few existing scheme has been proved secure in a formalized model, or acquired optimized performance. To achieve the goals of both proven security and high efficiency, this paper proposed an efficient identity-based proxy signature scheme. The scheme is constructed from bilinear pairing and proved secure in the random oracle model, using the oracle replay attack technique introduced by Pointehval and Stern. The analysis shows that the scheme needs less computation costs and has a shorter signature than the other schemes.
文摘Key escrow is an inherent disadvantage for traditional ID-based cryptosystem, i.e., the dishonest private key generator (PKG) can forge the signature of any user, meanwhile, the user can deny the signature actually signed by him/herself. To avoid the keyescrow problem, an ID-based signature scheme was presented without trusted PKG. The exact proof of security was presented to demonstrate that our scheme is secure against existential forgery on adaptively chosen message and ID attacks assuming the complexity of computational Diffie-Hellman (CDH) problem. Compared with other signature schemes, the proposed scheme is more efficient.
