A Secure Scheme for Heterogeneous Wireless Sensor Networks Based on Grids and Symmetric Polynomials

A scheme for WSNs (wireless sensor networks) security is given by dividing sensing tetrahedron into clusters and using the symmetric polynomials in this paper. The sensing tetrahedron is divided into a number of small grids. All those sensor nodes, both ordinary sensor nodes and heterogeneous sensor nodes are distributed in the sensing tetrahedron. In a grid, all ordinary sensor nodes and heterogeneous sensor nodes establish their shared keys through using the symmetric polynomials. All the heterogeneous sensor nodes establish their shared keys through using the symmetric polynomials. At last, all sensor nodes establish their keys directly or indirectly in the whole sensing tetrahedron. Analysis and comparison demonstrate this scheme enhances the WSN security, has good network connectivity, saves node storage, reduces network computing load, and extends the network lifetime. Introduction Wireless sensor networks have various applications and have received considerable attention by researchers all over the world. Wireless sensor networks consist of many small devices called sensor nodes, of course, sometimes, they comprise several kinds of sensor nodes. One kind of sensor nodes are called ordinary sensor nodes, and other kinds of sensor nodes are called heterogeneous sensor nodes which generally have more powerful abilities. We name the wireless sensor networks which consist of ordinary sensor nodes and heterogeneous sensor nodes heterogeneous wireless sensor networks. Those sensor nodes in wireless sensor networks are linked by wireless transmission medium. In general, those sensor nodes have some unique characters, including low battery energy, limited communication capacity, low computation ability, etc. Additionally, in order to fulfil their applications, sometimes, wireless sensor networks are distributed in unfriendly or even hostile environment. So, wireless sensor networks are susceptible to various vicious attacks . Guaranteeing the wireless sensor networks secure is an of importance task in order to finish the wireless sensor networks applications. The key management scheme that hinders the activities of malicious sensor nodes is an efficient method to ensure wireless sensor networks security. Those key management strategies in paper [4] and [5] guarantee the wireless sensor networks secure through using the symmetric polynomials. In the two schemes sensor nodes set up their shared keys through utilizing the symmetric polynomials. In the paper, we give a key management strategy based on grids for the security of wireless sensor networks. In this scheme, the sensing tetrahedron is divided into a number of grids. All sensor nodes, both ordinary sensor nodes and heterogeneous sensor nodes, are dispensed in the whole sensing tetrahedron. In each grid, two kinds of sensors establish their common keys through using the symmetric polynomials. In the entire sensing tetrahedron, all heterogeneous sensor nodes also set up their shared keys through using the symmetric polynomials. Finally, all sensor nodes in the whole sensing tetrahedron set up their shared keys directly or indirectly. Analysis and comparison show that this scheme enhances the security of WSNs, and has good network connectivity. 3rd International Conference on Machinery, Materials and Information Technology Applications (ICMMITA 2015) © 2015. The authors Published by Atlantis Press 743