Research On Cpabe-based Data Access Control And Ciphertext Search Technology In The Internet Of Things Environment

With the rapid development and large-scale application of the Internet of Things technology,the era of the Internet of Everything has arrived.On the basis of the Internet,people connect objects with objects through the network,which makes information exchange more convenient and brings more benefits to people's daily lives.With the improvement of the Io T system,the applicable big data cloud computing technology is also applied to the Io T technology.As a centralized data processing center,a large amount of heterogeneous Internet of Things data is processed and calculated.However,at the same time as these technologies have evolved,security issues have become increasingly important.In the Internet of Things environment,the scale of the Io T nodes is huge and varied,which has caused the characteristics of massive and heterogeneous data in the Io T.How to ensure the privacy and security of heterogeneous Io T data,how to perform fine-grained access control on a large amount of Io T data,how to retrieve Io T data on the basis of ensuring data privacy,etc.are main issues currently faced by Io T technology.Meanwhile,the limited computing power of Io T nodes also complicates these issues.In view of the above problems,the research work of this dissertation mainly includes the following three contents:(1)By analyzing the characteristics of Io T data,a data normalization description in the context of Io T data is proposed.By analyzing the application scenarios and design goals of the solution,the file is selected as the data description method to achieve data normalization.The file structure and data format are described by the data normalization,and the heterogeneous Io T data is generated as a file.The data's fine-grained access control function while ensuring data integrity and confidentiality is supported by the description.It enables the Io T data to be shared and exchanged securely in the Io T system in a uniform format.(2)As requirements for security and fine-grained access control in the data normalization description in the Io T environment,a lightweight CPABE(CK-CPABE)scheme is designed.Based on ciphertext attribute-based encryption,an asymmetric encryption scheme that implements fine-grained access control is proposed.Corresponding access policies and ciphertexts based on the data attribute set is generated by the scheme while the data access control and encryption functions is completed.At the same time,a method of constructing a polynomial is used to generate a fixed-length key while having a low computational complexity,which makes it easy to store and update the key in the Io T device node.Finally,it is proved that the scheme is indistinguishable by choosing plaintext attacks,ensuring the security of the scheme.(3)Based on the CK-CPABE scheme,a CPABE-based fast document ciphertext search(CSCPABE)scheme for fast multi-keyword ciphertext search of documents is proposed.With the use of attribute-based encryption technology,different attribute keywords through line-oriented mapping is integrated,an efficient ciphertext search algorithm that supports multi-attribute search is proposed by the solution.In addition,the algorithm is indistinguishable from keyword selection attacks is proved,which guarantees the privacy and security of search keywords.(4)The CK-CPABE and CS-CKABE schemes are implemented,and on basis of them,the data normalization description method in the Internet of Things environment is implemented in the form of files..The performance of the CK-CPABE and CS-CKABE solutions are tested in an actual environment to verify that the solutions can run efficiently in Io T devices.In the meantime,the performance changes of the solutions are compared under different experimental equipment,and the impact of the computing power of the equipment is analyzed on the performance of the algorithm.