LLK: A link-layer key establishment scheme for wireless sensor networks

The establishment of link-layer keys between neighboring nodes is a fundamental issue in securing sensor network communications. Most of existing solutions are key pre-distribution schemes which rely on sensor nodes to broadcast hundreds of or even thousands of pre-loaded key IDs to find pairwise keys between neighboring nodes. The shortcomings include poor resilience against node compromise, low network connectivity, large communication overhead, etc. This paper presents a novel location-based link-layer key establishment scheme, in which a hexagonal-grid-based deployment model and a polynomial-based key establishment model are combined for the first time to establish a link-layer key between two neighboring nodes. Compared with conventional proposals, our scheme features much lower communication overhead and memory requirements while still maintaining high network connectivity and network resilience against node compromise.