Security architecture & threat model
Detailed technical specification for security architects, CISOs, and platform engineers evaluating the cryptographic boundaries and threat mitigations implemented across RedactNode.
RedactNode adheres to a strict zero-knowledge proxy architecture. Identifiers are tokenized at the enterprise boundary, transient mapping keys are isolated in volatile memory with enforced TTLs, and upstream AI vendors never receive customer personal data in cleartext.
1. Cryptographic Primitives
Standardized industry algorithms applied across data in-transit, session memory, and tamper-evident audit trails:
| PRIMITIVE | PURPOSE | SECURITY SPECIFICATION |
|---|---|---|
| AES-256-GCM Envelope Encryption | Session Token Vault Mappings | Every token-to-PII mapping pair is encrypted using authenticated 256-bit Galois/Counter Mode before writing to in-memory Redis storage. |
| HMAC-SHA256 Cryptographic Signatures | Audit Event Immutability | Audit metadata digests are sealed using HMAC-SHA256 signatures, ensuring non-repudiation proof during regulatory investigations. |
| Volatile RAM Session Expiry | Zero-Persistence Key Shredding | Session keys expire automatically via Redis TTL (default 15 minutes). No cleartext keys or mapping pairs are ever flushed to persistent disk. |
| Chromium Manifest V3 Isolated World | Client-Side DOM Protection | Tanda Guard extension content scripts execute in isolated worlds, completely invisible and inaccessible to malicious webpage JavaScript. |
2. In-Memory Vault Lifecycle
The token vault stores the reversible lookup table between synthetic surrogate tokens and cleartext PII. It enforces the following security boundaries:
VAULT_ENCRYPTION_KEY to decrypt.3. Chrome MV3 Isolated Worlds
When using Tanda Guard in employee browsers, content scripts run within Chromium's Manifest V3 Isolated World execution environment:
4. Threat Matrix & Mitigations
Comprehensive threat vectors evaluated during enterprise penetration testing:
