Research On Multi-user Searchable Encryption Without Trusted Third Party

In the era of big data,users are gradually migrating data to cloud servers to efficiently store,manage,and share data.It also brings user privacy and data security issues.Although traditional data encryption technology can effectively protect user data security,users cannot effectively retrieve ciphertext data.On the issue of ciphertext search,academia has proposed searchable encryption technology.Among them,the many-tomany searchable encryption scheme is the most complicated and most suitable for practical application scenarios.At present,most of the many-to-many searchable encryption needs to rely on the existence of a trusted third party in reality.It is very important to research significance and application value that reducing the dependence on trusted third parties for the many-to-many searchable encryption schemes.This article does the following research on searchable encryption and secure data sharing without trusted third parties:1.Based on the problem that most many-to-many searchable encryption schemes rely on trusted third parties,we constructed a verifiable multi-user searchable encryption scheme without trusted third parties.Both the data owner and data users do not interact with third parties.The owner does not rely on a trusted third party to generate a secure index while achieving fine-grained autonomous authorization management.Data users generate trapdoors alone and trapdoor size is constant.Besides,the data users can check whether the server is fully performing the search process and verify the correctness of the results returned by the server.Finally,we show that the scheme is safe and efficient through security proof and the efficiency comparison experiment analysis2.For the problem of secure data sharing,we present a traceable secure data sharing searchable encryption scheme.We still implement user fine-grained permissions management without relying on trusted third parties.At the same time,the idea of key aggregation is used to optimize the communication overhead of the authorization token in scheme one,so that the size of the authorization token in scheme two is constant.In addition,using the idea of aggregate group signatures,sharing users can track users who maliciously leak keys.Finally,we analyze security and efficiency,and show that the scheme is safe and efficient.