Research On Ciphertext Search Method For Cloud Storage

With the increasing maturity of cloud computing and cloud storage technologies,incompletely trusted cloud servers also provide some security issues while providing services to enterprises and individual users.While data encryption technology guarantees data security,it also brings some difficulties to the effective use of data(such as information retrieval).Therefore,how to effectively solve the search problem on ciphertext data while protecting the privacy of the data has become an important issue to be solved urgently in recent years.This article focuses on the existing ciphertext search scheme and its core technology-Searchable Encryption(SE),and researches the existing scheme from three aspects:ciphertext search mode,encryption primitives,and key issues to be solved.Perform classification analysis to improve overall expression,efficiency and safety.For different application scenarios,three ciphertext search solutions are proposed to meet different needs.First,a cross-language multi-keyword ranking search scheme is proposed.In multi-language scenarios,it is necessary to provide query support for different languages.Most existing cipher text search solutions only support single-language queries.In response to this problem,combined with natural language processing technology,multi-language multi-keyword cipher text is proposed Search solutions,and intelligent and personalized searches with flexible keyword and language preferences.In addition,an efficient privacy protection ciphertext sorting protocol is proposed to speed up the sorting process.Secondly,an authoritative semantic search scheme based on concept map is proposed.Due to the multi-user nature and dynamic changes of Internet applications,search authorization and dynamic updates have become key issues that need to be addressed in this scenario.Aiming at this problem,a semantic and authorization search scheme with dynamic update and fast response is proposed,and a file-level fine-grained search authorization is realized.By constructing the user's personal dictionary,dynamic updates and efficient index generation are achieved.Finally,a distributed data security retrieval scheme based on the alliance blockchain is proposed.Because the traditional cloud server-centric cipher text search scheme cannot meet the requirements of trusted queries,a distributed secure retrieval scheme based on the alliance blockchain is proposed.By using the blockchain technology,transparent and immutable features and searchable Encryption technology enables a secure and trusted search of sensitive data.Distributed calculation of search algorithms through smart contracts,dynamic division of transactions,and formulation of adaptive endorsement strategies to achieve the best query efficiency.Based on the above three schemes,the security analysis is performed for each security model,and the prototype system and simulation experiments are established to verify the expressiveness,availability and efficiency of the system.