Andrew Allison

Lachlan J. Gunn, Andrew Allison, Derek Abbott

Decentralized systems can be more resistant to operator mischief than centralized ones, but they are substantially harder to develop, deploy, and maintain. This cost is dramatically reduced if the decentralized part of the system can be made highly generic, and thus incorporated into many different applications. We show how existing anonymization systems can serve this purpose, securing a public database against equivocation by its operator without the need for cooperation by the database owner. We derive bounds on the probability of successful equivocation, and in doing so, we demonstrate that anonymization systems are not only important for user privacy, but that by providing privacy to machines they have a wider value within the internet infrastructure

Lachlan J. Gunn, Andrew Allison, Derek Abbott

The Kish key distribution system has been proposed as a class ical alternative to quantum key distribution. The idealized Kish scheme elegantly promise s secure key distribution by exploiting thermal noise in a transmission line. However, we demonstrate that it is vulnerable to nonidealities in its components, such as the finite resistance of the transmission line connecting its endpoints. We introduce a novel attack against this nonideality using directional wave measurements, and experimentally demonstrate its efficacy. Our attack is based on causality: in a spatially distributed system, propagation is needed for thermodynamic equilibration, and that leaks information.

Lachlan J. Gunn, James M. Chappell, Andrew Allison et al.

While information-theoretic security is often associated with the one-time pad and quantum key distribution, noisy transport media leave room for classical techniques and even covert operation. Transit times across the public internet exhibit a degree of randomness, and cannot be determined noiselessly by an eavesdropper. We demonstrate the use of these measurements for information-theoretically secure communication over the public internet.