Enhancing privacy with quantum networks

Abstract

Using quantum networks to distribute symmetric keys has become a usable and commercial technology available under limitations that are acceptable in many application scenarios. The fact that the security is implemented directly at the hardware level, and moreover, relies on the laws of physics instead of conjectured hardness assumptions, justifies the use of quantum security in many cases. Limitations include 100 km communication range and installation of quantum channels between each pair of users of the network. Presently, with the current lack of trust in commercial security solutions, mostly due to the Snowden crisis, there is the need to improve such solutions. In this paper we discuss how quantum networks can be used to setup secure multiparty computation (SMC), allowing for instance for private data mining, electronic elections among other security functionalities. SMC relies mostly on establishing an efficient oblivious transfer protocol. We present a bit-string quantum oblivious transfer protocol based on single-qubit rotations that can be implemented with current technology based on optics and whose security relies only on the laws of physics. © 2014 IFIP International Federation for Information Processing.