Research On Multi-receiver Signcryption Schemes

In this big data era that network technology is increasingly mature and rapidly development,the people demand has become increasingly complicated and diversified about the information security.In order to solve the different security problems of different network environments,and to meet people's security needs preferably,the digital signcryption must add some additional properties.The Multi-receiver signcryption technology already has developed for more than 30 years since it was proposed;it has evolved from an absolutely abstract concept into a standardized signcryption technology which owns the standard formal definition and the perfect security model.It has already become an important branch of the cryptography.Multi-receiver signcryption is a hot topic of the cryptography.In recent years,a large number of multi-receiver signcryption schemes have been proposed.Unfortunately,there have many security problems in the existing multi-receiver signcryption schemes,such as: the information of the sender and the receiver directly were exposed by the ciphertext especially;the unfair problem of decryption often happened.Besides,the existed schemes still have many limitations in some specific environments.The purpose of this paper is to design more secure,efficient and practical multi-receiver signcryption scheme by combining the multi-receiver signcryption and other signcryption systems,so that the proposed multi-receiver signcryption schemes can meet the different security needs and can be applied to diverse environments.The paper has the following three research contributions:1.In order to solve the defect of anonymity and confidentiality in the exsited multireceiver signcryption scheme,an anonymous certificateless multi-message multi-receiver signcryption scheme was proposed in this paper.The proposed scheme combined the advantages of ring signcryption and multi-receiver signcryption,it has solved the anonymity problem and the confidentiality problem when multiple messages were sent to multiple receivers.In the random oracle model,the proposed scheme was proved to be secure.2.In order to get over the problem of key leakage of Wang Caifen's scheme,an improved multi-message multi-receiver hybrid signcryption scheme was proposed in this paper.The improved scheme overcame the key leakage defects of Wang's scheme,and the confidentiality and unforgeability of the improved scheme were proved in the random oracle model.3.Proposed a forward security certificateless multi-receiver proxy signcryption scheme by combining signcryption and proxy signature.The proposed scheme was based on certificateless,and it utilized the key update mechanism to decrease the loss of the keyleakage.The confidentiality of the proposed scheme was proved in random oracle model;the unforgeability,forward security and distinguishability of the proposed were also analyzed in this papaer.