2 research outputs found
How to Test the Randomness from the Wireless Channel for Security?
We revisit the traditional framework of wireless secret key generation, where
two parties leverage the wireless channel randomness to establish a secret key.
The essence in the framework is to quantify channel randomness into bit
sequences for key generation. Conducting randomness tests on such bit sequences
has been a common practice to provide the confidence to validate whether they
are random. Interestingly, despite different settings in the tests, existing
studies interpret the results the same: passing tests means that the bit
sequences are indeed random.
In this paper, we investigate how to properly test the wireless channel
randomness to ensure enough security strength and key generation efficiency. In
particular, we define an adversary model that leverages the imperfect
randomness of the wireless channel to search the generated key, and create a
guideline to set up randomness testing and privacy amplification to eliminate
security loss and achieve efficient key generation rate. We use theoretical
analysis and comprehensive experiments to reveal that common practice misuses
randomness testing and privacy amplification: (i) no security insurance of key
strength, (ii) low efficiency of key generation rate. After revision by our
guideline, security loss can be eliminated and key generation rate can be
increased significantly