Multi-Layer E2EE Architecture
COMPLETED Arc PRODUCT SPECIFICATION
Arc core specification
Arc's core specification is ML-KEM-1024/PQXDH, E2EE, Sender Keys, Sealed Sender, IGF, and offline Mesh. This Security page documents the scope and technical details.
PQXDH Key Exchange
COMPLETED Arc PRODUCT SPECIFICATION
Double Ratchet
COMPLETED Arc PRODUCT SPECIFICATION
AES-256-GCM Encryption
COMPLETED Arc PRODUCT SPECIFICATION
XEdDSA Signatures (libsignal)
COMPLETED Arc PRODUCT SPECIFICATION
Client-Side Sealed Sender
COMPLETED Arc PRODUCT SPECIFICATION
Comparison with 20 Major Messengers
Competitor cards link to first-party sources. Arc's card is bound to its completed product specification and the same scoring model.
ML-KEM-1024 Parameters
NIST FIPS 203 standardized post-quantum Key Encapsulation Mechanism.
| Algorithm | ML-KEM-1024 (via libsignal-client) |
| NIST Security Level | Security category 5 |
| Classical Security | 2^128 bit (X25519) |
| Quantum Security | NIST security category 5 |
| Foundation | Module Lattice (FIPS 203) |
| Public Key Size | 1,184 bytes |
| Secret Key Size | 2,400 bytes |
| Ciphertext Size | 1,088 bytes |
Compliance & Standards
🇺🇸NIST CSF 2.0
NIST framework. 6 functions for systematic cyber risk management.
🇺🇸NIST SP 800-53
Federal security controls. FedRAMP foundation.
🇺🇸FIPS 140-3
COMPLETED Arc PRODUCT SPECIFICATION
🇺🇸NIST SP 800-175B
Cryptographic algorithm selection guide. Based on FIPS 203.
🌐ISO/IEC 27001
International ISMS certification. B2B/B2G trust foundation.
🇪🇺GDPR
EU General Data Protection Regulation. World's highest protection standard.
🇬🇧UK Cyber Essentials+
UK government-certified cybersecurity certification.
🇬🇧NCSC Cloud Security
UK NCSC 14 Principles. Cloud security assessment standard.
Developed in compliance with all prerequisites of US NIST, EU GDPR, UK NCSC, and international ISO.
System Architecture Documentation
COMPLETED Arc PRODUCT SPECIFICATION
15+ Technical Sections
Layer architecture, PQC implementation, encryption pipeline, data storage, and more
Bilingual (EN/JP)
Full documentation available in English and Japanese with one-click toggle
Version 3.1 — March 2026
COMPLETED Arc PRODUCT SPECIFICATION
This document is classified as confidential and available exclusively to NDA-bound partners, investors, and authorized technical reviewers. Access requires prior approval by Atlas Associates.