# Recording Hardware

Our hardware is designed to be used on the premise that it connects to a smartphone as a Bluetooth device.

## Tamper-Resistant Design

Our device ensures authenticity through hardware security:

* Secure Element chip stores cryptographic keys and controls signing operations.
* Device generates a unique key-pair during first-time initialization.
* Keys never leave the Secure Element, preventing extraction or duplication.

## Time-Locked Recording Process

A fundamental principle: **At least n hours are required to push n hours of data**

The recording process follows a strict protocol:

1. Device retrieves a unique nonce from Solana program (`init`)
2. Audio is captured in fixed n-minute blocks.
3. Secure Element signs each block with a time-locked signature.
   1. \*Device ensures signing process cannot be called multiple times within n-minute.
4. On-chain verification checks that `received_audio_hours ≤ elapsed_hours_since_init`

Device can only emit one signature per n minutes, enforcing real-time progression. (processed within Secure Element)

## High-Fidelity Capture

The hardware includes specialized components for quality recording:

* Dual high-frequency stereo microphones. (used for fraud protection as well)
* Extended frequency response. (up to 48kHz)
* Challenge Tone Speaker. (Secure Element generates random ultrasonic sequences that must be captured in the recording.)