具有隐私性保护的基于身份的多接收者加密方案

Multi-receiver ID-based Encryption Scheme with Privacy Protection

多接收者加密可以被用于很多重要场合,如先付费电视系统、流媒体服务等;这些应用中,只有授权或者付费的用户才能获得服务。针对现有基于身份的多接收者加密方案存在的暴露接收者身份、计算代价过高等问题,提出了一个具有隐私性保护的多接收者加密方案。新方案密文中不包含接收者身份列表,以保护接收者隐私;每个接受者在解密前便可验证自己是不是授权用户,避免大量不必要的解密开销。对比现有方案在真正意义上实现了接收者匿名性,并且加解密效率优势明显,可以用于不安全和开放网络环境中的敏感消息广播。

Multi-receiver identity-based encryption can be used for many important applications such as pay-TV or streaming audio/video services. In all the applications, only the paid users or a privileged set of receivers can get the services. Some secure problems are found：in the existing multi-receiver identity-based encryption scheme, that is, disclosure of the recipients＇ privacy and high computational cost. In order to solve these problems, a new multi-receiver identity-based encryption scheme with privacy protection is presented. Ciphertext of the proposed scheme does not contain a list of receiver identities, which can protect the receivers＇ privacy. Furthermore, each receiver can verify whether he/she is an authorized user before the decryption, which avoids much unnecessary decryption overhead. Analysis results show that this scheme is a secure and effective encryption scheme and it can be used to broadcast sensitive information in unsafe and open network environment.