Research On Signcryption System With Equality Test And Its Application

How to ensure the security of data is a research hotspot in modern society.The primitive of encryption is considered to be an effective solution to address this problem.Nevertheless,the encrypted ciphertexts are faced with the challenge of reducing data availability.The traditional searchable encryption scheme can search the aforementioned ciphertexts,but this technology only supports the ciphertexts encrypted by the same public key.In view of this limitation,the concept of public key encryption with equality test is introduced,which can match the ciphertext encrypted by the same or different public keys without decryption.Although the encryption technology can guarantee the integrity and confidentiality of the data,it can not ensure the unforgeability of the data.Therefore,the primitive of signcryption emerges as the times require.However,the existing signcryption schemes with equality test have the problem of low performance and are only suitable for a single environment.This thesis makes a comprehensive study of the above problems and completes the following works.For addressing the high overhead of the existing signcryption schemes with equality test,this thesis proposes an identity-based signcryption scheme with equality test in the Internet of Vehicles(Io V).This scheme inherits the advantages of identity-based signcryption and equality test,which addresses the problem of certificate management in the existing scheme and greatly reduces the computing and communication overhead in the process of information transmission.In addition,the integrity,confidentiality and unforgeability of data are guaranteed simultaneously.Aiming at the complex and changeable heterogeneous environment,this thesis proposes a heterogeneous signcryption scheme from identity-based cryptosystem(IBC)to public key infrastructure(PKI)with equality test in the wireless body area networks(WBANs).The proposed scheme can address the problem that the existing scheme is only suitable for a single system.Meanwhile,the construction of scheme has reduced the number of bilinear pairings and hash functions,which makes the signcryption and unsigncryption process more efficient than the existing schemes.Besides,the proposed scheme can apply to a heterogeneous environment and the security has also been demonstrated.In order to further adapt to the heterogeneous environment,this thesis proposes a heterogeneous signcryption scheme from PKI to certificateless cryptosystem(CLC)with equality test towards the Internet of things(Io T),in which the data transmission is between two heterogeneous systems.The sender in PKI system can signcrypt data and then upload the ciphertext to the cloud server.When a user in CLC system requires the specific data,the equality test is performed to determine whether the different ciphertexts contain the same plaintext.Meanwhile,the provable security theory proves the security of the proposed scheme,the simulation experiment shows the time overhead of the presented scheme and verify that it can better adapt to the IoT environment.