# Multi-party quantum summation based on quantum teleportation

## TL;DR

This paper introduces a secure multi-party quantum summation protocol utilizing quantum teleportation, ensuring privacy and security against various attacks, with robustness against loss errors.

## Contribution

It proposes a novel quantum summation protocol based on teleportation that is secure against participant and outsider attacks, and resistant to loss errors.

## Key findings

- Protocol is secure against participant and outsider attacks.
- Participants' private bits remain confidential without state transmission.
- Protocol is robust against loss errors due to single entanglement distribution.

## Abstract

We present a secure multi-party quantum summation protocol based on quantum teleportation, in which a malicious, but non-collusive, third party (TP) helps compute the summation. In our protocol, TP is in charge of entanglement distribution and Bell states are shared between participants. Users encode the qubits in their hand according to their private bits and perform Bell-state measurements. After obtaining participants' measurement results, TP can figure out the summation. The participants do not need to send their encoded states to others, and the protocol is therefore congenitally free from Trojan horse attacks. In addition, our protocol can be made secure against loss errors, because the entanglement distribution occurs only once at the beginning of our protocol. We show that our protocol is secure against attacks by the participants as well as the outsiders.