Based On Combinatorics Key Management Scheme Of Heterogeneous Wireless Sensor Networks

The heterogeneous wireless sensor network is a new kind of wireless network, which draws lessons from Ad Hoc networks and the wireless sensor networks. It assumes the differences between the structure and the function of the nodes. Compareing with the nodes have the same structure and function in WSN, heterogeneous wireless sensor networks can significantly improve the network lifetime, the network connectivity, the network scalability and the resilience toward node capture. As the technology development, the heterogeneous wireless sensor networks will be more widely applied, and its security problems will be concerned deeply. Key management is the base of all kinds of security mechanism. Therefore, how to use the heterogeneous characteristics of the nodes and designing an effective key management scheme for the heterogeneous wireless sensor networks has become a significant problem.Firstly, this paper makes a systematic survey about static key management for wireless sensor networks. This paper depicts not only the problem of the key management, but also evaluation metrics of the key management. Moreover, several typical schemes for key management of wireless sensor networks problems are reviewed, and the taxonomy are described. More specifically, these schemes are discussed in detail, and advantages and disadvantages of the schemes are summarized. Then, the combinatorial design theory foundation knewledge is introduced, especially, the pairwise balanced design. These contents are the foundations of our research.In the thesis, a static key management model that controls key distribution and networks' construction of the heterogeneous nodes for the heterogeneous wireless sensor networks. The model describes the static security booting system and the static security maintenance system in details. The key pre-distribution scheme of the heterogeneous wireless sensor networks based on the pairwise balanced design is introduced in constructing key ring module of the static security booting system. The heterogeneous characters of our model have been fully reflected.As the research emphasis, we using the discrepancy of common nodes and cluster head nodes in heterogeneous wireless sensor networks, constructed the heterogeneous key chain of nodes based on divisible core pair-wise balanced design, and designed key pre-distributed schemes, DCPBD and VDCPBD. DCPBD was based on the divisible core pair-wise balanced design (termed of PBD), and the common blocks map as the common node's key chains and the particular blocks map as the cluster head's key chains. VDCPBD was extended from DCPBD, and also the single core was replaced by another key pool which is designed by SBIBD, and decreased the influence of the single cluster head's compromise and enhanced the networks' survivability. As we considered the heterogeneous attribute in design, and the certainty method to construct the heterogeneous key chains and acquire lower space complexity without changing the key connectivity in these two schemes.Simulation shows that both of two schemes sustain large-scale networks and, as the networks' scale increases, the single hop key connectivity approaches to 1, the double hop key connectivity is 1 constantly by matlab. VDCPBD also has better resilience against node capture and better networks' extensibility.