RoK is a new key pre-distribution scheme for multi-phase wireless sensor networks that allows sensors of different generations,
i.e. deployed at different times, to establish secure channels .
 - C.Castelluccia and A. Spognardi:
RoK: A Robust Key Pre-distribution Protocol for Multi-Stage Wireless Sensor Networks, 3rd International Conference on Security and Privacy in Communication
Networks - SecureComm'07, Nice, France, September 2007.