RELIABLE AND A RIGID REFINED ASPECT-BASED DATA REPOSITORY IN CLOUD COMPUTING ENVIRONMENT

Abstract

With the development of cloud computing, outsourcing data to cloud server attracts lots of attentions. To guarantee the safety and achieve flexibly fine-grained file access control, attribute based encryption (ABE) was proposed and used in cloud storage system. However, user revocation is the primary issue in ABE practices. In this article, we provide a ciphertext-policy attribute based encryption (CP-ABE) proposal with efficient user revocation for cloud storage system. The issue of user revocation can be solved efficiently by introducing the concept of user group. When any user leaves, the group manager will update users’ private keys except for those who have been revoked. Additionally, CP-ABE scenario has heavy reckoning sell for, as it grows linearly with the complexity for the access structure. To reduce the estimation lose, we outsource high calculation load to cloud service providers without leaking file content and secret keys. Notably, our strategy can withstand collusion attack performed by revoked users comply real users. We end up the safety of our blueprint lower than the portable estimation Diffie-Hellman (DCDH) hypothesis. The results of our exercise shows calculation take for inhabitant devices are comparatively low and may comply. Our blueprint is acceptable for capital unnatural devices.