---
id: NET-002
title: Secure Device Pairing Protocol
status: Done
assignee: james
parent: NET-000
priority: High
tags: [networking, security, pairing]
whitepaper: Section 4.5.2
---

## Description

A secure protocol for pairing two devices will be implemented. The flow uses a human-readable BIP39 mnemonic code to establish a secure, end-to-end encrypted session, after which devices are mutually trusted.

## Implementation Notes

- The complete state machine and logic will be implemented in `src/services/networking/protocols/pairing/`.
- The `PairingProtocolHandler` manages the initiator and joiner roles.
- Cryptographic operations, including challenge-response using `ed25519-dalek`, are handled by `pairing/security.rs`.
- Multi-process integration tests (`device_pairing_test.rs`, `device_persistence_test.rs`) validate the real-world functionality.

## Acceptance Criteria

- [x] An initiator can generate a 12-word pairing code.
- [x] A joiner can use the code to discover and connect to the initiator.
- [x] Devices successfully exchange keys and establish a trusted relationship.
- [x] Paired device information is persisted securely for automatic reconnection.