云环境下SNS隐私保护方案

社交网络存储的数据实际都是外包给并不完全可信的云服务商。针对社交网络隐私安全和属性更新问题,提出一种云环境中具有策略隐藏和属性撤销的属性基加密方案。通过分解密钥产生方式降低用户端的计算量,引入合数阶的双线性群实现访问策略隐藏,并利用令牌树和陷门机制灵活且高效地完成属性撤销。而且,该方案在标准假设下可被证明是安全的。因此,将该方案运用于社交网络,将数据加密存储于云服务端是安全可行的。与其他方案相比,该方案既保护了访问策略的隐私,又具有多样的访问控制功能,在计算和存储等方面更有优势。

Privacy Preserving Scheme for SNS in Cloud Environment

In reality,data stored on social networks are often outsourced to the untrusted cloud services providers.Aiming at the problems of privacy and attribute updating of social network,an attribute-based encryption scheme with hidden policy and attribute revocation in cloud environment was proposed.This scheme reduces the computation of clie-nt by breaking down the way of key generation.Moreover,the policy is hidden by using the composite order bilinear groups,and a mechanism with token tree and attribute trapdoor is used to achieve an efficient and flexible attribute re-vocation.In addition,the scheme is proved to be secure under the standard assumption.So,using this encryption in socialnetwork service to encrypt data to cloud servers is safe and feasible.Compared to other related works,this scheme protects the privacy of access policy and gives a better performance in computing and storage with access control functions.