批量密钥更新中密钥组织方法的研究与实现

在对批量密钥更新和成员行为进行分析的基础上,对现有的优化密钥树结构进行了优化,并给出了一种实现方法.该方法基于Huffman树的构造方法,将组成员的变化概率与成员所在的密钥树级别进行关联,形成多级密钥树,最低级别密钥树高度为1.成员变化概率越大,所在的密钥树级别越低.当成员变化概率发生动态改变时,成员的位置也可随之更改.这种方法较好地解决了多播组中异构成员变化带来的组密钥更新问题.仿真实验结果表明,提出的优化树结构更具有一般意义,可适应具有较大动态变化情形的安全多播密钥更新.

Research and implementation of group key management in batch group rekeying

Based on batch group rekeying and group members' behavior,a new method which optimizes the current key tree structure is proposed.The method is based on the extending of traditional Huffman tree.It expands the group member's model of uniform probability to a diverse one,and establishes the relationship of member change probability with one of the multi-lever-key trees.The height of the lowest tree is 1.The bigger the probability of a member,the lower the tree height in it.When members' probabilities change,their locations can be changed afterwards.The method can solve the problem of group rekeying with heterogeneous group members.Simulation results show that the method is more generalizing than others and is more adaptive to secure multicast group with various group behaviors.