Abstract
Sensor network comprises of scattered sensor nodes with limited computational capabilities and battery power. The existing security solutions for traditional wireless networks can not be used because of the constraints associated with sensor network. We present secure sink node architecture as two-tiered scheme for sensor network security. The architecture protects the sink node from unauthorized access by surrounding it with two protection layers. Sink nodes listen to only inner layer nodes and inner nodes are allowed to communicate with only outer layer nodes. These protection layers are formed in an intelligent manner without violating constraints specific to sensor network. In order to enhance security, protection layers are re-adjusted in case of an attack. We present statistical analysis to elucidate the performance of proposed architecture.