A simple protocol for verifiable delegation of quantum computation in one round

TL;DR

This paper introduces a simple, one-round protocol for verifiable quantum computation delegation to two servers, which is secure even with server communication under relativistic constraints, simplifying previous multi-round protocols.

Contribution

It presents the first one-round, two-server quantum delegation protocol that is conceptually simpler and secure under relativistic assumptions.

Findings

First one-round protocol for quantum delegation to two servers.

Security holds even if servers communicate, assuming relativistic constraints.

Protocol's parameters enable security proofs under realistic physical assumptions.

Abstract

The importance of being able to verify quantum computation delegated to remote servers increases with recent development of quantum technologies. In some of the proposed protocols for this task, a client delegates her quantum computation to non-communicating servers in multiple rounds of communication. In this work, we propose the first protocol where the client delegates her quantum computation to two servers in one-round of communication. Another advantage of our protocol is that it is conceptually simpler than previous protocols. The parameters of our protocol also make it possible to prove security even if the servers are allowed to communicate but respecting the plausible assumption that information cannot be propagated faster than speed of light, making it the first relativistic protocol for quantum computation.