Secure Quantum Handshakes: Quantum Network Verification Via Simon's Algorithm

This repository contains an implementation of a pedagogical approximation of a quantum network admission protocol using classical communication. A client uses a quantum computer to query a Simon oracle and returns the recovered hidden string to a server, which checks the answer and the response time. Because the client receives the oracle implementation, a classical attacker may recover the hidden string without quantum queries; this approximation does not verify quantum network integrity. See the associated paper for the full protocol description: https://arxiv.org/abs/2610.12209.

Table of Contents

• Introduction
• Structure
• Usage
• License

Introduction

This repository implements a classical-communication variant of a quantum network admission protocol, designed as a pedagogical tool for exploring how the secure protocol works. In the variant, a prospective participant uses a quantum computer to query a Simon oracle, recover its hidden string, and return that string to the network operator. The operator admits the participant only if the answer is correct and arrives within a specified time limit.

Because the oracle's implementation must be shared with the participant, a classical attacker could potentially recover the hidden string without making quantum queries. The protocol therefore does not verify quantum network integrity; it instead offers a practical way to build intuition about the secure protocol. Implementations for IBM quantum devices and simulators are provided.

Structure

The repository structure is as follows:

adiabatic-simons-algorithm/
├── simon_handshake.py                # Executes approximate network verification
├── test_oracle.py                    # Tests the oracle function
├── noisySimulations/                 # Code and results for noisy simulations
├── figures/                          # Contains figures for the paper
├── archive/                          # Old code, data, and figure files
├── .gitignore                        # Git ignore file (e.g., system files)
├── LICENSE                           # License file
└── README.md                         # Project description and instructions

Of these files, simon_handshake.py is the most important, as it allows for the execution of the classical approximation to the quantum network verification protocol. Following this, the files in the noisySimulations directory will be useful to those looking to reproduce the results of our paper.

Usage

To begin, clone the repository. To run the approximate network verification protocol, first set the parameters at the top of the simon_handshake.py file. Next, start two parallel terminal instances; execute python simon_handshake.py alice in the first, and python simon_handshake.py bob in the second. The terminals will then record the logs as Alice (the server) and Bob (the client) complete the handshake.

License

This project is licensed under the MIT License — see the LICENSE file for details.