The Research On Dynamic Attribute-based Encryption Algorithm For Cloud Storage

Cloud Computing is a practical and effective technique to facilitate computing, and as its extension clouding storage has been solved problems regarding big data storage. Cloud storage, as a convenient storage service, plays an important role in many fields. However, with the fast development of technique, users’ security requirement becomes more and more strict. At present, many cloud service providers provide simple access control which is totally relied on their server-side. Generally, the cloud service provider is not100%trustworthy that data would give to a third party without permission of its user. The user’s information maynot be confidential, so the cloud storage has potential security problem. The traditional public key encryption system and subsequent ciphertext access control scheme can only archive coarse-grained access control,which is ineffective, out-of-date, and incompetent for users’ security requirement.In recent years, dynamic attribute-based encryption becomes a hot topic in cloud storage area as well as in network security issues. But there still exist many deficiencies and problems to be resolved, forexample, in the traditional ABE scheme, the process of authorization management for most users are staticoperation, which means if someone wants to update, revoke or delete an access control structure, he mustencrypt the entire data file by the lien again. Therefore, the availability and efficiency of the traditionalABE scheme will very insufficient. This thesis proposes a scheme which is “Attribute dynamic basedencryption” on the basis of traditional ABE scheme. The meaning of the scheme proposed by this thesis isstudy further for the modern cryptography theory. Meanwhile, this scheme can improve the availability andefficiency of the cloud storage technology in network application.This thesis is consisted of five chapters,Chapter one: Introduction. It introduces background and significance of this thesis, and present itsacademic necessity based on the literature review. Then, it introduces the core concept and structure of thethesis.Chapter Two: Study the basic knowledge and application. It introduces some foundation ofmathematics (Algebra basic theorem, Lagrange interpolation and bilinear mapping) in this scheme. Andthis chapter also introduces some mathematical assumptions, provable security model, and access controland access control tree. Then this chapter illustrates the application of this knowledge in the ABE scheme.Chapter Three: The ABE scheme and dynamic implementation scheme.This chapter is core content of this thesis. It introduces the security assumptions and algorithm implementation of “Attribute dynamicbased encryption” scheme. Then it describes the scheme of “Attribute dynamic based encryption” which isthe core content of this thesis. When the users process the authorization management, adopted a dynamicproperty management solutions, namely for key cipher and attribute set update, cancel or delete, only needto dynamically adjust the access structure can be completed, which reduces the data file is encrypted againthe system overhead, and the whole plan of the specific implementation process. In the end of this chapter,a professor to upload a paper and set the access control permissions, to guarantee the safety of upload thepaper as an example to illustrated the scheme and its realization is.Chapter Four: Analysis of “Attribute dynamic based encryption” scheme. Obtained by test analysisand experimental comparison, the scheme has reached the expected effect of want, greatly reduces theoverhead of the system, to improve the performance of the conclusion.Chapter Five: Conclusion and Implications. First of all, it concludes the work has been done in thisthesis, and provides questions for future studies. Then, it analysis the current network technique----thedevelopment tendency of cipher system in the framework of cloud storage. Finally, it provides implicationsfor future studies in this area.