Key management is considered as the fundamental part of any secure communication. A secure wireless sensor network communication protocol relies on an efficient key management system. In sensor networks some random pre-distribution schemes are proposed for key management protocols. Connectivity and resiliency are two important criteria in key management. There is a trade-off between connectivity and resiliency in random key pre-distribution since increasing one decreases the other one and vice versa. In this paper we propose a new key management scheme in heterogeneous wireless sensor networks in which tradeoff between these criteria is lower than other schemes. This scheme consists of four stage key pre-distribution, localization and seed assignment, deriving new keys and shared key discovery. Simulation and analytical results show that proposed scheme has higher connectivity and resiliency and needs lower storage space compared to AP and EG key management schemes.

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