Dylan Gray

2papers

2 Papers

CROct 9, 2017
XYZ Privacy

Josh Joy, Dylan Gray, Ciaran McGoldrick et al.

Future autonomous vehicles will generate, collect, aggregate and consume significant volumes of data as key gateway devices in emerging Internet of Things scenarios. While vehicles are widely accepted as one of the most challenging mobility contexts in which to achieve effective data communications, less attention has been paid to the privacy of data emerging from these vehicles. The quality and usability of such privatized data will lie at the heart of future safe and efficient transportation solutions. In this paper, we present the XYZ Privacy mechanism. XYZ Privacy is to our knowledge the first such mechanism that enables data creators to submit multiple contradictory responses to a query, whilst preserving utility measured as the absolute error from the actual original data. The functionalities are achieved in both a scalable and secure fashion. For instance, individual location data can be obfuscated while preserving utility, thereby enabling the scheme to transparently integrate with existing systems (e.g. Waze). A new cryptographic primitive Function Secret Sharing is used to achieve non-attributable writes and we show an order of magnitude improvement from the default implementation.

CRFeb 28, 2017
MPC Validation and Aggregation of Unit Vectors

Dylan Gray, Joshua Joy, Mario Gerla

When dealing with privatized data, it is important to be able to protect against malformed user inputs. This becomes difficult in MPC systems as each server should not contain enough information to know what values any user has submitted. In this paper, we implement an MPC technique to verify blinded user inputs are unit vectors. In addition, we introduce a BGW circuit which can securely aggregate the blinded inputs while only releasing the result when it is above a public threshold. These distributed techniques take as input a unit vector. While this initially seems limiting compared to real number input, it is quite powerful for cases such as selecting from a list of options, indicating a location from a set of possibilities, or any system which uses one-hot encoding.