State-based key management scheme for wireless sensor networks

In wireless sensor networks, the random key pre-distribution arises as the practical solution for sharing common keys between sensor nodes. Since sensor networks suffer from the resource constraints like limited memory space, key pre-distribution scheme should require less memory space as possible while supporting strong security strength, i.e., high resilience against node capture. However, the existing schemes still require a large number of keys for each sensor to carry. Although location information is facilitated as deployment knowledge for improvement, if two sensor nodes closely located each other have very low probability to be in active-state at the same time, unnecessary key assignments can be happened since keys shared only between them may be hardly used. In this paper, we propose a novel random key pre-distribution scheme that exploits new deployment knowledge, state of sensors, to avoid unnecessary key assignments and reduce the number of required keys that each sensor node should carry while supporting higher connectivity and better resilience against node captures. The analysis of our proposed scheme shows the better performance and security strength than the previous schemes