A Secure Group Sharing Framework Using TGDH Scheme

Cloud computing is a kind of Internet computing mainly used for data storage and data sharing. Secure data sharing among the group members is also an important concept in cloud. But privacy and security of users data are the major issues in cloud. And the semi trust nature of cloud service provider is also an important issue. Due to this semi-trusted nature of CSP traditional security mechanisms cannot be applied directly. . In this paper, we propose a secure group sharing framework using TGDH scheme for cloud computing, which can effectively take advantage of the Cloud Servers help without exposing any sensitive data to attackers and the cloud provider. This framework combines enhanced TGDH, proxy re-encryption, EIGamal signature generation and A-S algorithm together into a protocol. Enhanced TGDH scheme is used for the generation of dynamic group key pairs. Proxy re-encryption is adopted for ensuring forward and backward secrecy. Digital signatures are generated by the use of EIGamal algorithm with random key and group public key. A-S algorithm is used for data encryption. The security requirements for cloud based data sharing are fulfilled by our proposed scheme with high efficiency. And it can be proved by the extensive security and performance analysis.