One-Time Pad (OTP) Encryption - Jupyter Notebook

This repository contains a step-by-step Jupyter Notebook demonstrating the One-Time Pad (OTP) encryption algorithm. OTP is a classical cryptography technique that, when implemented correctly, provides perfect secrecy (information-theoretic security) and cannot be cracked, even with infinite computing power.

This notebook is structured for educational purposes, breaking down the encryption process into easily digestible chunks.

🚀 Overview

The notebook covers two main approaches to OTP encryption:

1. Custom Byte-wise Implementation: Demonstrates the core mathematics of OTP using the bitwise XOR (^) operation and cryptographically secure random keys generated via os.urandom().
2. Using External Libraries: Shows a quick, practical implementation using the onetimepad Python library for rapid prototyping.

💻 Installation & Usage

To run this notebook, you will need Jupyter installed on your system.

1. Clone the repository:

2. Install the required external library for the second section of the notebook:

   pip install onetimepad

3. Launch Jupyter Notebook:

   jupyter notebook

Open the .ipynb file and run the cells sequentially.

🧠 How It Works

The core of OTP relies on the XOR operation:

C = P ⊕ K

Where C is the Ciphertext, P is the Plaintext, and K is the Key.

For the encryption to be truly unbreakable, the key must follow three absolute rules:

1. It must be truly random (or generated by a Cryptographically Secure Pseudo-Random Number Generator like os.urandom()).
2. It must be at least as long as the plaintext.
3. It must never be reused in whole or in part.