Encryption Best Practices 2026: TLS 1.3, AES-256, Argon2 & Post-Quantum Readiness

Modern Cryptography Standards (2026)

TLS 1.3 Configuration

What Changed in TLS 1.3

Nginx TLS 1.3 Configuration

server {
    listen 443 ssl http2;
    server_name securecodereviews.com;

    ssl_certificate /etc/letsencrypt/live/securecodereviews.com/fullchain.pem;
    ssl_certificate_key /etc/letsencrypt/live/securecodereviews.com/privkey.pem;

    # TLS 1.2 minimum (TLS 1.3 preferred)
    ssl_protocols TLSv1.2 TLSv1.3;

    # Cipher suites (TLS 1.3 uses its own, TLS 1.2 uses these)
    ssl_ciphers ECDHE-ECDSA-AES256-GCM-SHA384:ECDHE-RSA-AES256-GCM-SHA384;
    ssl_prefer_server_ciphers off;

    # HSTS (2 years with preload)
    add_header Strict-Transport-Security "max-age=63072000; includeSubDomains; preload" always;

    # OCSP Stapling
    ssl_stapling on;
    ssl_stapling_verify on;
}

Data Encryption at Rest

AES-256-GCM (Authenticated Encryption)

import { createCipheriv, createDecipheriv, randomBytes } from "crypto";

// AES-256-GCM — Provides both encryption AND integrity verification
function encrypt(plaintext: string, key: Buffer): EncryptedData {
  const iv = randomBytes(12);  // 96-bit IV for GCM
  const cipher = createCipheriv("aes-256-gcm", key, iv);

  let ciphertext = cipher.update(plaintext, "utf8", "hex");
  ciphertext += cipher.final("hex");
  const authTag = cipher.getAuthTag();

  return {
    ciphertext,
    iv: iv.toString("hex"),
    authTag: authTag.toString("hex"),
  };
}

function decrypt(data: EncryptedData, key: Buffer): string {
  const decipher = createDecipheriv(
    "aes-256-gcm",
    key,
    Buffer.from(data.iv, "hex")
  );
  decipher.setAuthTag(Buffer.from(data.authTag, "hex"));

  let plaintext = decipher.update(data.ciphertext, "hex", "utf8");
  plaintext += decipher.final("utf8");
  return plaintext;
}

Critical Rules:

• Never reuse an IV with the same key (GCM catastrophically fails)
• Use authenticated encryption (GCM, ChaCha20-Poly1305) — not CBC
• Store encryption keys in KMS (AWS KMS, Azure Key Vault), never in code

Password Hashing

Argon2id (Recommended)

import argon2 from "argon2";

// Hash password with Argon2id
async function hashPassword(password: string): Promise<string> {
  return argon2.hash(password, {
    type: argon2.argon2id,
    memoryCost: 65536,   // 64 MB
    timeCost: 3,          // 3 iterations
    parallelism: 4,       // 4 threads
  });
}

// Verify password
async function verifyPassword(password: string, hash: string): Promise<boolean> {
  return argon2.verify(hash, password);
}

Hashing Algorithm Comparison

Post-Quantum Cryptography

Why Post-Quantum Matters Now

Quantum computers that can break RSA and ECC are estimated to arrive between 2030-2035. But:

• Harvest Now, Decrypt Later: Adversaries are collecting encrypted data today to decrypt when quantum computers arrive
• Migration takes years: Transitioning cryptographic infrastructure is a 3-5 year project
• NIST finalized standards in 2024: ML-KEM and ML-DSA are production-ready

Recommended Post-Quantum Algorithms

Hybrid TLS (Classical + Post-Quantum)

Chrome and Cloudflare already support hybrid key exchange using X25519 + ML-KEM-768, protecting against both classical and quantum attacks.

Common Cryptographic Mistakes

Further Reading

• NIST Post-Quantum Cryptography — PQC standards
• Password Security Guide — Password hashing deep dive
• PCI DSS 4.0 Compliance — Encryption requirements
• OWASP Cryptographic Failures — A02 vulnerability guide