Research On Application Of Matchmaking Encryption

Matchmaking encryption is an emerging public key cryptosystem that allows receivers and senders to choose their own access policies to control data access rights.Specifically,matchmaking encryption allows senders and receivers to specify access structures to display messages and allows receivers to determine whether the ciphertext came from an approved sender.However,the existing matchmaking encryption schemes still have certain limitations.Firstly,they can only guarantee coarse-grained access control to data and no in-depth research has been done on bilateral access control with fine-granularity schemes.Secondly,in terms of security,the current schemes only derive security in the general group model.However,under the standard model and random oracle model,there is currently a lack of provably secure fine-grained matchmaking encryption schemes.To a certain extent,these problems limit the development and application of matchmaking encryption cryptosystem in cloud computing.To tackle these issues,in the thesis,an in-depth study and analysis of the matchmaking encryption scheme is carried out.The research results are as follows:Firstly,the thesis proposes a cloud-based lightweight access control scheme.The scheme combines matchmaking encryption and attribute-based encryption scheme,which achieves fine-grained bilateral access control.In the process of encryption key generation,the authenticity of the message is protected by signature.And the verification scheme is performed by trusted authority,which reduces the pressure of the user signature verification.At the same time,the thesis proves the proposal not only can achieve the indistinguishability under chosen-plaintext attacks but also realize the existence unforgeability under chosen message attacks.In addition,this also proposed scheme is applied to the industrial Io T(IIo T)healthcare.By comparing the theory and experiment with other related cryptographic primitives with similar functions,the practicability and security of the proposed scheme in IIo T are proved.Secondly,in view of the exposure risk of encrypted data in the case of user key loss in the cloud computing environment,the thesis proposes a puncturable attribute-based matchmaking encryption scheme with privacy and confidentiality under random prediction model by combining attribute-based matchmaking encryption scheme and the puncturing encryption scheme.More importantly,not only ensure the key size of the proposal is consistent with that of the attribute-based matchmaking encryption scheme,also the thesis compares the proposed scheme with other related schemes.On the one hand,it proves that the proposed scheme can not only achieve bilateral access control with fine-grainularity,but also ensure the forward security of encrypted messages.On the other hand,it is proved that the proposal outperforms other related schemes between the properties and the performance of computation and storage cost,which indicates the proposal can meet the actual encryption requirements in practical use.Moreover,the applicability and function of the scheme in online car-hailing service system are explained in detail.