混合云环境下密文数据的访问控制技术研究

Access control is the key technology of hybrid cloud security, which could ensure the access and usage of data reasonable, legal and efficient. Considering the characteristics of the construction and data in hybrid cloud, this project aims to solve the existing problems of the cryptograph access control in hybrid cloud and focus on the following three aspects:1) To abstract the process of data exchanging in hybrid cloud, analyze the grading and laying methods for the management of users and data, then propose the multi-layer cryptograph access control model and its policy describing method. 2) For the problems of users' complicated calculation and difficult key management in the current cryptograph access control, propose the multi-layer access control system and cryptograph construction algorithm based on proxy re-encryption. 3) To do some research on the implementation of access control based on third-party, design the key management scheme for the trusted updating by combining the proxy re-encryption and self-destruction, and finally form the solution of access control deployment based on third-party. We will solve the key problems including the consistency of access control policies description in hybrid cloud and trusted updating of cryptograph, and achieve the novel results of multi-layer cryptograph access control model, cryptograph construction and key management, which will ensure the efficiency and security of cryptograph access control in hybrid cloud.

访问控制是保障混合云安全的关键技术，它能够确保在复杂混合云环境下数据被合理、合法、高效的访问与使用。本项目结合混合云的结构和数据特点，针对现有混合云密文访问控制技术研究中存在的问题，重点开展三方面研究：1）抽象混合云环境下数据交互的流程，分析用户和数据的分层、分级管理方法，提出层次化的密文访问控制模型及其策略描述方法；2）针对密文访问控制面临的用户计算量大、密钥管理难度大等问题，提出基于代理重加密的层次化访问控制系统及密文构造算法。3）研究基于第三方的访问控制实现策略，结合代理重加密、安全自毁等技术，设计支持可信更新的代理重加密密钥管理方法，最终形成基于第三方的访问控制部署方案。本项目将重点解决混合云环境中密文访问控制策略描述的一致性问题与密文可信更新问题，在混合云密文数据层次化访问控制模型、重加密密文生成与密钥管理方面进行创新，确保混合云密文访问控制执行的有效性和安全性。