Signcryption is a public key cryptographic method that achieves unforgeability and confidentiality simultaneously with significantly smaller overhead than that required by "digital signature followed by public key en...Signcryption is a public key cryptographic method that achieves unforgeability and confidentiality simultaneously with significantly smaller overhead than that required by "digital signature followed by public key encryption". It does this by signing and encr.ypting a message in a single step. An aggregate signcryption scheme allows individual signcryption ciphertexts intended for the same recipi- ent to be aggregated into a single (shorter) combined ciphertext without losing any of the security guarantees. We present an aggregate signcryption scheme in the identity-based setting using multilinear maps, and provide a proof of security in the standard model. To the best of our knowledge, our new scheme is the first aggregate signcryption scheme that is secure in the standard model.展开更多
In order to protect historical ciphertext when the private key leaked in the broadcasting system,the forward-secure multi-receiver signcryption scheme is designed based on the generic graded multilinear mapping encodi...In order to protect historical ciphertext when the private key leaked in the broadcasting system,the forward-secure multi-receiver signcryption scheme is designed based on the generic graded multilinear mapping encoding structure,which effectively prevents illegal access from intruder to the ciphertext in the past time period when the private key in current time period is revealed.Through the generalization of the existing multilinear mapping encoding system,it proposes the generic graded multilinear mapping encoding structure and the generic graded decision Diffie-Hellman problem.Because of the generic graded multilinear mapping encoding system adopted,almost all candidate multilinear mapping encoding systems can automatically adapt to our scheme.Under the assumption of generic graded decision Diffie-Hellman problem,it has proved that the scheme has the information confidentiality and unforgeability in the current time period.After putting forward the security model of forward-secure multi-receiver signcryption scheme,and under the assumption of generic graded decision Diffie-Hellman problem,it has proved that the scheme has the message forward-confidentiality and forward-unforgeability.Compared with other forward-secure public key encryption schemes,the relationship between our scheme and time periods is sub-linear,so it is less complex.展开更多
文摘Signcryption is a public key cryptographic method that achieves unforgeability and confidentiality simultaneously with significantly smaller overhead than that required by "digital signature followed by public key encryption". It does this by signing and encr.ypting a message in a single step. An aggregate signcryption scheme allows individual signcryption ciphertexts intended for the same recipi- ent to be aggregated into a single (shorter) combined ciphertext without losing any of the security guarantees. We present an aggregate signcryption scheme in the identity-based setting using multilinear maps, and provide a proof of security in the standard model. To the best of our knowledge, our new scheme is the first aggregate signcryption scheme that is secure in the standard model.
基金Sponsored by the National Natural Science Foundation of China(Grant No.61401226,61672270,61602216)the MOE(Ministry of Education in China) Project of Humanities and Social Sciences(Grant No.14YJAZH023,15YJCZH129)+2 种基金the Basic Research Program of Jiangsu University of Technology(Grant No.KYY14007)the Qing Lan Project for Young Researchers of Jiangsu Province of China(Grant No.KYQ14004)the Open Fund of State Key Laboratory of Information Security,Institute of Information Engineering,Chinese Academy of Sciences(Grant No.2015-MSB-10)
文摘In order to protect historical ciphertext when the private key leaked in the broadcasting system,the forward-secure multi-receiver signcryption scheme is designed based on the generic graded multilinear mapping encoding structure,which effectively prevents illegal access from intruder to the ciphertext in the past time period when the private key in current time period is revealed.Through the generalization of the existing multilinear mapping encoding system,it proposes the generic graded multilinear mapping encoding structure and the generic graded decision Diffie-Hellman problem.Because of the generic graded multilinear mapping encoding system adopted,almost all candidate multilinear mapping encoding systems can automatically adapt to our scheme.Under the assumption of generic graded decision Diffie-Hellman problem,it has proved that the scheme has the information confidentiality and unforgeability in the current time period.After putting forward the security model of forward-secure multi-receiver signcryption scheme,and under the assumption of generic graded decision Diffie-Hellman problem,it has proved that the scheme has the message forward-confidentiality and forward-unforgeability.Compared with other forward-secure public key encryption schemes,the relationship between our scheme and time periods is sub-linear,so it is less complex.