一个基于随机函数族的新广播加密方案  

A New Broadcast Encryption Scheme Based on a Family of Random Functions

作　　者：赖霞[1] 陈利娅[1] 何明星[1] 

机构地区：[1]西华大学数学与计算机学院,四川成都610039

出　　处：《武汉大学学报（理学版）》2008年第5期623-625,共3页Journal of Wuhan University:Natural Science Edition

基　　金：国家自然科学基金(60473030);教育部科学技术重点项目(205136);四川省科技厅重点项目(05JY029-131)

摘　　要：通过构建一个随机函数族,本方案可成功地为用户分配密钥,使合法用户以概率为1地获得解密,而用户的密钥存储仅为(l+1)个.在系统开始运行前,每一个用户从每一个密钥池获得一个密钥.对于退出用户,广播中心只需用他们所不拥有的其他(辅助)密钥加密会话密钥即可;而对于未退出用户,在一定程度上他们总可以找到一个密钥与广播中心在加密会话密钥时所使用的密钥相匹配.本方案较目前基于二叉树结构的广播加密方案(如SD)在密钥存储量上有显著的优势,同时在一定条件下可使传输成本最小.In this paper, we present a broadcast encryption scheme based on a family of random functions. The scheme can securely distribute keys, and each user can decrypt the message with 1 probability while he storages keys only. Before the system starts each user draws a key from each key pool. To revoke a set of users,GC simply uses the keys not held by these users and encrypts the session key update with other （auxiliary）keys. With a certain probability,a remaining user will have a key matching what GC has used to encrypt the session key with. The scheme is far better in key storage than many hierarchical binary tree based schemes, such as SD, and can reduce the transmission cost to minimum under some conditions.

关 键 词：广播加密 随机函数族 多方退出 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]