Abstract: Effective key management scheme is the foundation for the secure communication of wireless sensor networks.A key management scheme for hierarchical wireless sensor networks is proposed，which takes advantages of the proposed energy-aware tree to balance energy consumption of cluster nodes.All the nodes in the network are organized in an energy-aware tree，the edges of which carry weight decided by the remaining power of the nodes.The root of each tree distributes different messages to the nodes according to the edges’ weight.To enhance the security of cluster heads，Blom matrix was adopted in generating inter-cluster keys.Analysis shows that the proposed scheme can effectively save the constrained energy of sensor nodes，provide high scalability of the network as well as network resilience ability.

Key words: wireless sensor network, key management, energy-aware tree, Blom matrix

摘要： 有效的密钥管理方案是实现传感器网络安全通信的前提。针对分簇式无线传感器网络，提出一种基于能量树的密钥管理方案。将网络中节点按树型结构进行管理，并将每个节点的能量值作为树中各边的权值，树根按权值分发不同的秘密信息。簇头间通信密钥借助Blom矩阵的思想生成。分析表明，该方案有效地节省了节点的能量，并提供了较强的可扩展性、节点的抗捕获性和网络的可靠性等安全性能。

关键词: 无线传感器网络, 密钥管理, 能量树, Blom矩阵