安全多播中基于成员行为的LKH方法  

An LKH Method Based on the Behavior of Group Members in Secure Multicast

作　　者：许勇[1,2] 陈恺[1,2] 

机构地区：[1]东南大学计算机科学与工程系 [2]计算机网络和信息集成教育部重点实验室(东南大学),江苏南京210096

出　　处：《软件学报》2005年第4期601-608,共8页Journal of Software

基　　金：国家自然科学基金~~

摘　　要：LKH(logical key hierarchy)方法是安全多播实时密钥更新中常用的方法.LKH对所有成员的行为没有进行区分,在具有相同成员变化概率的情况下,具有较高的效率.但当组成员具有不同的变化概率,或者成员行为模式不同时,LKH的效率与最佳值的差距将会变大.在已知成员变化概率的情况下,可对LKH方法进行一定的改进,但要确切了解每个成员的变化概率,事实上是不可能的.R-LKH(Refined-LKH)方法无须准确了解组成员的变化概率,在已知基本成员变化信息的基础上,先将组成员分为活跃成员和非活跃成员两部分,分别将其安排在密钥树的不同位置,然后通过引入“脏路径”的概念,以尽可能地减少同一路径上密钥的反复更新,从而达到了减少管理者加密次数,降低通信开销的目的.仿真实验结果表明,在对多播组成员的行为方式进行“大致”区分的情况下,R-LKH方法比LKH有较大的优势.LKH (logical key hierarchy) is a basic method in secure multicast group rekeying. LKH is efficient in real time group rekeying since it does not distinguish the different probability among the group members. However when members have diverse changing probability or different changing modes, the gap between LKH and the optimal algorithm will become bigger. If the probabilities of members have been known, LKH can be improved someway, but the changing probability of members can not be known exactly. Based on the basic knowledge of group members, in R-LKH (Refined-LKH), the active members and inactive members are partitioned and set on different locations in the logical key tree firstly. Then the concept “dirty path” is introduced in order to reduce the repeated rekeying overhead in the same path. All these can decrease the number of encryption in group manager and the network communication overhead. The simulation result indicate that R-LKH has a better improvement over LKH if the multicast group members’ behavior could be distinguished “approximately”.

关 键 词：逻辑密钥树 密钥更新 脏路径 活跃成员 非活跃成员 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]