Research On Verifiable Private Match Based On Cloud Outsourcing

Private match is an important research content in the information security.It is also a basic tool for designing security protocols.It has a wide range of applications in human genome research,homeland security and social network.Private match means that there are many participants who have their own set of elements and want to compute the common element.The participants compute the set intersection without revealing their own private information.After the compute of private match is completed,the participants can obtain the common element.The result is that the participants can not know the private data information of other participants except the final intersection.The existing multi-party private match protocol has the problem of fairness and low query efficiency.Aiming at the problem that the existing multi-party private match protocol is inefficient and applicate in the cloud outsourcing environment will cause the leakage of participants' private data,a cloud-outsourcing multi-party private match protocol based on paillier homomorphic encryption and Bloom filter is proposed.The protocol converts the ciphertext encrypted by each participant's public key into the ciphertext encrypted by the same public key by using the NTRU-based proxy re-encryption algorithm,and outsources a large amount of computation to the cloud server.Then,the Bloom filter has the advantages of lower computational complexity,higher space utilization and higher query efficiency,and improves the efficiency of encrypting,decrypting and querying information in the protocol computation process.Ultimately,the participants only need a small amount of computation during the running of the protocol and do not need to interact.The problem of fairness cannot be effectively addressed for existing private match protocols.A decentralized based on cloud outsourcing private match protocol is proposed.In the protocol,we combined the threshold homomorphic encryption and Bloom filter to realize a decentralized multi-party private match protocol without trusted third party.We use smart contract to perform verification computations.If the dishonest behavior of participants is detected,they will be fined.Finally,the participants have incentive to implement the protocol honestly and each participant can get the match result.Finally,a formal protocol security analysis is given,and corresponding proofs are given and compared with other private match protocols.The experimental results of the protocol show that our protocol can run well and has practicability.The match result can be computed without revealing the participant's private information to meet the needs of the real application.