Initial commit - 611 cybersecurity skills across all subdomains

skills/implementing-end-to-end-encryption-for-messaging/references/standards.md

@@ -0,0 +1,40 @@
+# Standards and References - End-to-End Encryption for Messaging
+
+## Signal Protocol Specifications
+
+### The Double Ratchet Algorithm
+- **URL**: https://signal.org/docs/specifications/doubleratchet/
+- **Description**: Core key management algorithm for E2EE messaging
+
+### The X3DH Key Agreement Protocol
+- **URL**: https://signal.org/docs/specifications/x3dh/
+- **Description**: Initial key exchange using Extended Triple Diffie-Hellman
+
+### The Sesame Algorithm
+- **URL**: https://signal.org/docs/specifications/sesame/
+- **Description**: Multi-device session management
+
+## Cryptographic Standards
+
+### RFC 7748 - Elliptic Curves for Security (X25519)
+- **URL**: https://www.rfc-editor.org/rfc/rfc7748
+- **Description**: X25519 Diffie-Hellman key exchange
+
+### RFC 5869 - HKDF (HMAC-based Key Derivation Function)
+- **URL**: https://www.rfc-editor.org/rfc/rfc5869
+- **Description**: Key derivation for chain key updates
+
+### RFC 8032 - Edwards-Curve Digital Signature Algorithm (Ed25519)
+- **URL**: https://www.rfc-editor.org/rfc/rfc8032
+- **Description**: Identity key signatures
+
+### NIST SP 800-38D - AES-GCM
+- **URL**: https://csrc.nist.gov/publications/detail/sp/800-38d/final
+- **Description**: Authenticated encryption for messages
+
+## Python Libraries
+
+### cryptography
+- **X25519**: `cryptography.hazmat.primitives.asymmetric.x25519`
+- **HKDF**: `cryptography.hazmat.primitives.kdf.hkdf`
+- **AES-GCM**: `cryptography.hazmat.primitives.ciphers.aead.AESGCM`