Research On Attribute-based Keyword Search Technology In Cloud Computing

Cloud computing,a rapid calculation of growth in recent years,has caused a fundamental change in the field of information computing.It has the very large scale,virtualization,high reliability,high scalability,on-demand service,extremely low-cost and other features.Therefore,cloud computing has the unprecedented cost effectiveness,users can fully enjoy the benefits of cloud computing.In the cloud-computing model,due to its low cost and high performance,people are increasingly inclined to deliver a large amount of data that needs to be stored and complicated calculations to the cloud server.That can alleviate the storage and computational overhead of the local server.However,cloud servers that people use in this mode are typically provided by third-party providers,we cannot completely guarantee its safety.After the user data is uploaded to the cloud server,some malicious service providers may peep,steal,and modify the user information to violate privacy and have illegal profits.Therefore,the problem of data security and user privacy protection in cloud storage has also become one of the biggest problems in the development of cloud computing.For data security and user privacy concerns,data owners need to encrypt the data,which is outsourced to the cloud server.At the same time,users often search his files of interest by using specific keywords.Therefore,traditional plain text keyword search technology cannot meet people's needs.Therefore,how to realize efficient search of users in data encryption environment and secure access of users has become one of the most urgent problems in keyword search under the cloud environment.This prompted the development of attribute-based keyword search technology.In this paper,we mainly study the issues of attribute-based keyword search privacy protection in the cloud environment.The main research work is as follows:First of all,we briefly introduce the cloud-computing model and the technical background about searchable encryption and attribute based encryption.Then,the current research status of existing attribute encryption and keyword search schemes are described in detail.In addition,we analyze the advantages and disadvantages of above schemes.Secondly,in response to the issue of user revocation in the keyword search,we propose an attribute-based keyword search with efficient revocation scheme.In contrast to traditional keyword search technology,attribute-based keyword search focuses on the user's attributes.When the user sends a search request,the system determines whether the user has the power of search based on the user's attributes.To ensure that the cloud server can perform a secure search without knowing the true values of the index and trapdoor,we systematically construct a novel secure search protocol.Authenticated data users can issue a query without knowing the secret keys of these different data owners.At the same time,we use the administration servers as the trusted authority(TA).The encrypted indices and the trapdoors,which generated by the data owner and the user,can be transmitted to the cloud server through the administration servers after re-encryption,and efficient revocation of the user is realized.Thirdly,in the attribute-based keyword search scheme,there is a problem that the computation cost is too high when the user encrypts the attribute locally.Therefore,we propose an online/offline attribute-based keyword search scheme.In the scheme,we use online/offline ABE technology and outsource ABE technology to reduce the online calculation cost and the local calculation cost of users.Moreover,we implement the fine-grained access control for the user.Security analysis demonstrates that the scheme can achieve trapdoor unlinkability,keyword security,data privacy security and search controllability.Efficiency analysis shows,in terms of the computation overhead,the scheme is more practical and efficient than existing approaches.Finally,we analyze and summarize the issues of attribute-based keyword search privacy-protection in cloud computing,and point out the future research direction.