Abstract: With the development of Internet of things technology which is considerably contributed to the research of Heterogeneous Wireless Sensor Networks（HWSNs）, the design of key management schemes and protocols is one of the most important aspects of HWSNs research. Besides, the key management in HWSNs meets many new challenges due to its intrinsic properties. This paper proposes a Hybrid Key Management Scheme（NHKM） which is based on Elliptic Curve Cryptography（ECC） and symmetric cryptosystem, through the use of the certificate and nonce signature to achieve authentication of the node’s public key, thus well avoid Man-in-Middle（MIM） attack. The simulation results show the overall effectiveness of the NHKM scheme, revealing better performance in terms of resource cost, network connectivity, scalability and resilience.

Key words: heterogeneous sensor networks, Elliptic Curve Cryptography（ECC）, certificates, nonce signature, man-in-middle attack

摘要： 物联网技术的快速发展，使得异构传感网（HWSNs）得到了普遍应用，HWSNs的安全也引起了广泛关注。HWSNs安全性研究的重点问题之一是密钥管理方案及其协议的设计。HWSNs固有的特性使得密钥管理研究面临许多新挑战，提出了一种基于椭圆曲线加密（ECC）与对称密码体制的混合密钥管理方案NHKM，通过使用证书和不重数签名实现对节点公钥的认证，较好地避免了中间人攻击。仿真结果表明，NHKM方案与传统的密钥管理方案相比，具有更低的资源开销、更高的网络连通性、可扩展性和抗毁性。

关键词: 异构传感网, 椭圆曲线加密（ECC）, 证书, 不重数签名, 中间人攻击