Skip to content

README.md

Latest commit

 

History

History
36 lines (23 loc) · 2.64 KB

README.md

File metadata and controls

36 lines (23 loc) · 2.64 KB

Dead Sea Cipher

What It Is

Dead Sea Cipher is a browser-based interactive demo covering five eras of cryptographic history: Atbash (a simple Hebrew letter-substitution cipher from ~600 BCE), Caesar cipher (shift cipher), Vigenère cipher (polyalphabetic substitution), the One-Time Pad (XOR with a truly random key), and AES-256-GCM (authenticated symmetric encryption via the Web Crypto API with PBKDF2-SHA256 key derivation at 200,000 iterations). Each cipher is implemented in pure TypeScript with a live encoder/decoder and a working attack that demonstrates its fatal flaw — from Caesar brute-force to Kasiski examination to OTP key-reuse to GCM tamper detection. The security model progresses from no key space (Atbash) to computational security (AES-256-GCM symmetric authenticated encryption).

When to Use It

  • Teaching cryptographic history end-to-end — the demo walks from the oldest known cipher (Jeremiah's Atbash) to modern authenticated encryption in a single interactive timeline.
  • Demonstrating why each classical cipher fails — every panel includes a working attack so students can see the vulnerability firsthand rather than read about it.
  • Showing AES-256-GCM authenticated encryption in the browser — uses the Web Crypto API directly, with PBKDF2 key derivation, a random IV, and GCM integrity verification.
  • Exploring the Hebrew Bible's use of Atbash — the demo includes original Hebrew text rendering for Jeremiah 25:26, 51:1, and 51:41 with both Latin and Hebrew Atbash encoders.
  • Do not use this for production encryption — the demo is educational. Key material lives in the DOM and is never protected against side-channel extraction.

Live Demo

systemslibrarian.github.io/crypto-lab-dead-sea-cipher/

The demo presents a tabbed timeline (Atbash → Caesar → Vigenère → OTP → AES → Full Arc). Each tab lets you type plaintext, adjust parameters (e.g. Caesar shift 1–25, Vigenère keyword, AES passphrase), and see real-time encryption output. Every classical cipher tab includes a "Break It" button that runs the corresponding cryptanalytic attack live in the browser.

How to Run Locally

git clone https://github.com/systemslibrarian/crypto-lab-dead-sea-cipher.git
cd crypto-lab-dead-sea-cipher/demos/dead-sea-cipher
npm install
npm run dev

Part of the Crypto-Lab Suite

This demo is part of the Crypto-Lab collection of interactive cryptography demonstrations.

"So whether you eat or drink or whatever you do, do it all for the glory of God." — 1 Corinthians 10:31