With the pervasiveness of mobile communications, MSNs have become a promising networking paradigm for users to share\ncontents with others through mobile devices. This convenience comes at the cost of some serious security and privacy issues. In this\nwork, we propose a novel privacy-preserving scheme for MSNs, which can efficiently solve some of the most serious security and\nprivacy issues such as data confidentiality, fine-grained access control, and flexible revocation. In particular,we leverage the attribute\nbased encryption technique to realize fine-grained access control over encrypted data. Moreover, we enhance this technique and\ndesign a flexible and fine-grained revocation mechanism which enables not only efficient user revocation but also efficient attribute\nrevocation. As we show, our system can achieve both forward secrecy and backward secrecy using such mechanism.We compare\nour scheme with other related works and show that not only most of the previous works suffer from larger size of encrypted data\nbut also their decryption time grows linearly with the complexity of access policies. In comparison, our scheme achieves higher\nefficiency and smaller computation time while consuming lesser storage space. We provide extensive analysis and performance\nevaluation to demonstrate the security, scalability, and efficiency of our proposed framework.
Loading....