混合LKH密钥管理方案的存储最小化研究

在特定的密钥更新通信开销的情况下，研究了多播通信中基于混合LKH树的安全密钥管理方案问题。混合LKH树方案将含Ⅳ个成员的组划分为若干个含M个成员的簇，并将每个簇安置在密钥管理树的叶子结点上。根据簇大小，本文将组控制器的密钥最小存储开销表示为约束优化问题，再将约束优化问题转化为一个关于簇大小肘的不动点方程。当密钥更新通信开销约束为O（logN）时，证明不动点方程的最大根为簇大小肘的最优值，它使得混合LKH树的密钥存储开销达到最小。同时设计了一个最小化存储开销的算法。

Research on Minimizing Storage of Hybrid LKH Key Management Scheme

The problem of designing a storage efficient secure multicast key management scheme based on hy- brid tree for a prespecified rekey communication over- head is studied.A hybrid tree scheme divides a group of N members into clusters of M members and assigns each cluster to one leaf node of a key tree.Using this scheme,this paper formulates a constrained optimiza- tion problem to minimize the centralized group controller storage in terms of the cluster size M,then converts the constrained optimization into a fixed point equation and derives the optimal cluster siz M that leads to the mini- mal storage overhead,when the key update communi- cation constraint is given as.An algorithm that achieves minimal centralized group controller storage is designed.