Signcryption is a cryptographic primitive that performs signature and encryption simultaneously, at lower computational costs and communication overheads than the signature-then- encryption approach. In this paper, we...Signcryption is a cryptographic primitive that performs signature and encryption simultaneously, at lower computational costs and communication overheads than the signature-then- encryption approach. In this paper, we propose an efficient multi-recipient signcryption scheme based on the bilinear pairings, which broadcasts a message to multiple users in a secure and authenticated manner. We prove its semantic security and unforgeability under the Gap Diffie-Hellman problem assumption in the random oracle model. The proposed scheme is more efficient than re-signcrypting a message n times using a signcryption scheme in terms of computational costs and communication overheads.展开更多
Nowadays,indistinguishability against adaptive chosen-ciphertext attacks（IND-CCA2） has been widely accepted as a proper security criterion for encryption schemes.In this paper,an efficient conversion is proposed to ...Nowadays,indistinguishability against adaptive chosen-ciphertext attacks（IND-CCA2） has been widely accepted as a proper security criterion for encryption schemes.In this paper,an efficient conversion is proposed to satisfy the IND-CCA2 security.It uses the random oracle methodology and the idea of hybrid encryption,and can enhance any Diffie-Hellman based encryption scheme,which is only one-way under plaintext-checking attack.Compared with other existing conversions,this conversion has the advantages of short ciphertext and low computation overhead,especially when it is applied to the multi-recipient setting.展开更多
基金Supported by the National Natural Science Foundation of China (60473029)
文摘Signcryption is a cryptographic primitive that performs signature and encryption simultaneously, at lower computational costs and communication overheads than the signature-then- encryption approach. In this paper, we propose an efficient multi-recipient signcryption scheme based on the bilinear pairings, which broadcasts a message to multiple users in a secure and authenticated manner. We prove its semantic security and unforgeability under the Gap Diffie-Hellman problem assumption in the random oracle model. The proposed scheme is more efficient than re-signcrypting a message n times using a signcryption scheme in terms of computational costs and communication overheads.
基金Supported by the National Natural Science Foundation ofChina (60903178)
文摘Nowadays,indistinguishability against adaptive chosen-ciphertext attacks（IND-CCA2） has been widely accepted as a proper security criterion for encryption schemes.In this paper,an efficient conversion is proposed to satisfy the IND-CCA2 security.It uses the random oracle methodology and the idea of hybrid encryption,and can enhance any Diffie-Hellman based encryption scheme,which is only one-way under plaintext-checking attack.Compared with other existing conversions,this conversion has the advantages of short ciphertext and low computation overhead,especially when it is applied to the multi-recipient setting.
