An ID-based Proxy Signcryption Scheme with Fast Revocation
Yu Yong①; Yang Bo②; Li Fa-gen③; Sun Ying②
①National Key Lab. of ISN, Xidian University, Xi’an 710071, China; ②College of Information, South China Agricultural University, Guangzhou 510642, China; ③School of Computer Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
Abstract:Proxy signcryption schemes allow an original signcrypter to delegate his signcryption rights to a proxy signcrypter. However, the existing proxy signcryption schemes have the defect that can not solve the proxy revocation problem, that is, how to revoke the delegated signcryption rights of a proxy signcrypter. Based on the bilinear pairings, a new identity-based proxy signcryption scheme is proposed in this paper. A SEcurity Mediator (SEM) is introduced in the scheme to help a proxy signcrypter to generate valid proxy signcryptions, to examine whether a proxy signcrypter signcrypts messages according to the warrant, and to check the revocation of a proxy signcrypter. It is shown that the proposed scheme satisfies all the security requirements of a secure proxy signcryption scheme. Moreover, a proxy signcrypter must cooperate with the SEM to generate a valid proxy signcryption, which makes the new scheme has an effective and fast proxy revocation.