Research Of Certificateless Anonymous Multi-Receiver Signcryption Based On ECC

Multi-receiver signcryption plays an important role in one-to-many communication,which can simultaneously implement signature operation and encryption operation.Therefore,it is considered as an effective way to implement broadcast distribution of ciphertext.However,most of the existing multi-receiver signcryption schemes are identity-based,and there exists the key escrow problem,because the user's private key is independently generated by the Key Generation Center(KGC).That is,KGC knows the private key of all users.To avoid this problem,researchers proposed certificateless multi-receiver signcryption scheme.In the certificateless multi-receiver signcryption scheme,the private key of the user is composed of the secret value randomly selected by the user and the partial private key generated by KGC.Therefore,KGC does not know the user's private key,which solves the key escrow problem.At present,the research on certificateless multi-receiver signcryption has become the focus of information security.However,there are some shortcomings in most of the existing certificateless multi-receiver signcryption schemes.The use of bilinear pairing operations or the more number of the elliptic curve point multiplication operations lead to the low computational efficiency of the schemes.In addition to the sender,other receivers can also know the identity information of the authorized receivers,and the anonymity of the receivers are not achieved.Moreover,for the sake of solving the key escrow problem,most of the existing schemes set the user's private key into two parts,namely,the secret value and the partial private key,resulting in a large amount of the user private keys.In view of the above shortcomings,this paper proposes a certificateless anonymous multi-receiver signcryption scheme without bilinear pairing.In this scheme,the user uses the secret value selected randomly by himself,his own public key and the partial private key generated by KGC to calculate his own private key,which not only solves the key escrow problem,but also reduces the amount of the user private keys.The elliptic curve is used in the signcryption process to avoid the use of bilinear pair,and the number of elliptic curve point multiplication is much smaller than the existing schemes,so the computational efficiency of signcryption operations is improved.At the same time,polynomial technology is used to hide the receiver's identity information and protect the receiver's privacy.Subsequently,in-depth research and analysis of the previously proposed scheme,it is noted that the user and KGC interact with the partial private key through the secure channel,resulting in that the partial private key's security completely dependents on the secure channel during the interaction,and the system cost overhead is high.For the purpose of solving this problem,this paper continues to propose a certificateless anonymous multi-receiver signcryption scheme without secure channel.By calculating the user's pseudo-partial private key,the scheme avoids the dependence of the first scheme on the security channel when the user and KGC interact with the partial private key.By comparing and analyzing the two schemes in this paper,it is found that the first scheme has high computational efficiency,but the user needs to rely on the secure channel when interacting with KGC.The second scheme avoids the dependence on the secure channel,and it further improves the security and practicality of the scheme,but it is less computationally efficient than the first scheme.These two schemes in this paper achieve message confidentiality,receiver anonymity,and unforgeability.At the same time,these two schemes avoid the use of time-consuming bilinear pairings and reduce the number of elliptic curve point multiplication.Therefore,the schemes of this paper can be applied to the field of network broadcast signcryption services,cloud data sharing,and pay-TV in multicast networks.