Secure random number generation in wireless sensor networks

The increasing adoption of wireless sensor networks as a flexible and inexpensive tool for the most diverseapplications, ranging from environmental monitoring to home automation, has raised more and more atten-tion to the issues related to the design of specifically customized security mechanisms. The scarcity ofcomputational, storage, and bandwidth resources cannot definitely be disregarded in such context, and thismakes the implementation of security algorithms particularly challenging. This paper proposes a securityframework for the generation of true random numbers, which are paramount as the core building blockfor many security algorithms; the intrinsic nature of wireless sensor nodes and their capability of reliablyproviding measurements of environmental quantities make them natural candidates as true random num-ber generators. In order to provide robustness to common attacks, we additionally devised a protocol aimedat obscuring the actual source of data, by making nodes cooperate with their neighbors. Furthermore, wedescribe an enhanced version of our framework consisting in an optimization for use in the context ofresource-constrained systems.