Pairwise key establishment for large-scale sensor networks: from identifier-based to location-based

Letting two communicating parties share a key is an effective approach to achieve confidentiality and authenticity for their communications. If the parties know each other's id or are within each other's communication range, such a key can be set up using existing pairwise key establishment schemes. However, in sensor networks, there exist some communication patterns in which the sender only knows some attribute such as the rough location of its desired receiver, and the sender and receivers could be far apart. Directly extending the existing schemes to establish a pairwise key for such communicating parties is not efficient due to various reasons. To address the problem, we propose in this paper a new scheme that enables the two parties to securely communicate as long as they know each other's rough location. In this scheme, any two groups of nodes can set up a group-to-group (G2G) pairwise key based on their rough locations. Then the G2G key can be used to protect the communications between any two nodes in these groups. Extensive analysis and simulations are conducted to evaluate our approach. The results show that, by choosing the system parameters appropriately, a desired security level can be achieved without incurring high overhead.