Design and Development of End to End Email Encryption System Using ICP Blockchain

Abstract

In the modern digital era, traditional email systems remain vulnerable lacking end‑to‑end encryption, relying on centralized key management, and exposing users to breaches. We present the design and implementation of an enterprise‑grade end‑to‑end email messaging and file encryption system built on the Internet Computer Protocol (ICP) blockchain. Our system leverages MetaMask and Plug wallet–based authentication, Curve25519/XSalsa20‑Poly1305 encryption, and AES‑GCM for secure private‑key storage. A React+TypeScript frontend integrates with a Python/Flask backend, while ICP canisters store only ciphertext and immutable hashes, ensuring auditability without exposing plaintext. All cryptographic operations occur client-side, removing trust in centralized servers and minimizing backend attack surface. Performance evaluations on a 2.3 GHz Intel Core i5 system demonstrate sub‑2 ms key generation, under 6 ms round‑trip encryption/decryption for 10 000‑character payloads, and sub‑2 ms AES‑GCM key backup/restore. By eliminating single points of failure and meeting GDPR/HIPAA requirements through decentralized identity, our solution delivers real‑time secure communication suitable for enterprise deployment.