Key Levels and Securing Key Predistribution Against Node Captures  

       Jacek Cichon, Jaroslaw Grzaslewicz, Miroslaw Kutylowski
                 Wroclaw University of Technology

We consider  key predistribution schemes deployed for securing communication 
in ad hoc networks of tiny devices. As node captures are inevitable 
in these networks and the devices might be  not  tamper-proof, an adversary 
can collect the keys and decrypt some transmissions. 

We propose and analyze key levels technique that can be used on top of most 
 key predistribution schemes in order to reduce chances of an adversary. 
The modification does not increase  the number of keys loaded into a device,
while it increases the computational cost in an insignificant way. 
Also, it composes  well into a framework of adaptive key management allowing
to refresh the keys without causing incompatibility problems with the devices 
holding the old keys. Finally, we show have to reduce  the number of keys in 
a device for random key predistribution by an appropriate construction 
of the pool of keys. 

Keywords: key management, adversary, node capture, random key predistribution, 

ALGOSENSORS'2009, LNCS

work done within FRONTS Project