An essential requirement for providing secure services in wireless sensor
networks is the ability to establish pairwise keys among sensors. Due to
resource constraints on the sensors, the key establishment scheme should not
create signicant overhead. To date, several key establishment schemes have
been proposed. Some of these have appropriate connectivity and resistance
against key exposure, but the resources needed in the sensors are substantial.
Others are appropriate from the resource consumption perspective, but have
weak performance. This paper proposes a key establishment protocol based
on symmetric polynomials. To improve performance, the protocol uses a new
model to distribute polynomial shares to the sensors. A key feature of the
proposed protocol is the tradeo between performance, security and resource
consumption. Analysis shows that our solution has good performance compared
to other approaches.