Continuous-Variable Protocols in the Noisy-Storage Model

TL;DR

This paper introduces a continuous-variable quantum oblivious transfer protocol secure in the noisy-storage model, utilizing new uncertainty relations and analyzing security against realistic quantum memory limitations.

Contribution

It presents the first optical continuous-variable protocol for oblivious transfer with proven security in the noisy-storage model, including explicit security parameters.

Findings

Protocol achieves security by sending more signals than an attacker can store.

Derived new uncertainty relations for continuous-variable systems.

Provided security parameters for realistic quantum memory models.

Abstract

We present the first protocol for oblivious transfer that can be implemented with an optical continuous-variable system, and prove its security in the noisy-storage model. This model allows security to be achieved by sending more quantum signals than an attacker can reliably store at one specific point during the protocol. Concretely, we determine how many signals need to be sent in order to achieve security by establishing a trade-off between quantum uncertainty generated in the protocol and the classical capacity of the memory channel. As our main technical tool, we study and derive new uncertainty relations for continuous-variable systems. Finally, we provide explicit security parameters for realistic memory models.