Security & ArchitectureSeptember 9, 20266 min read

Tenant-Isolated Cryptographic Vaults, Ethical Walls, and Zero Foundation Model Training in Multi-Product Enterprise AI

An architectural review of how Zunn safeguards sensitive legal, tax, commerce, and voice data across all three enterprise platforms with immutable tenant isolation.

Fahim Shahriar

Lead Platform Security & Infrastructure Architect

1. The Enterprise Trust Imperative

For enterprise legal departments, tax practices, and consumer retail brands, cloud AI adoption stalls when security teams cannot verify data containment boundaries.

If client legal briefs, corporate trial balances, or customer support phone recordings are mixed into global model training sets, trade secrets and privileged communications are permanently compromised.

Zunn was built with security as a mathematical constraint rather than an operational afterthought. We enforce physical and cryptographic tenant boundaries at every layer of our stack.

2. Cryptographic Tenant Isolation

Every customer organization in Zunn operates within a dedicated tenant vault. Vector embeddings, document text, customer communications, and voice tokens are encrypted at rest with AES-256 using tenant-specific cryptographic keys.

Cross-tenant data queries are prevented by database row-level security (RLS) policies and separate cryptographic key namespaces, making data leakage across tenants mathematically impossible.

PostgreSQL Row-Level Security Policy for Tenant Vaults

-- Enforce strict tenant boundary at the database layer
ALTER TABLE tenant_document_vaults ENABLE ROW LEVEL SECURITY;

CREATE POLICY tenant_isolation_policy ON tenant_document_vaults
  FOR ALL
  TO authenticated_app_role
  USING (tenant_id = current_setting('app.current_tenant_id', true)::uuid)
  WITH CHECK (tenant_id = current_setting('app.current_tenant_id', true)::uuid);

3. The Absolute Zero-Training Guarantee

We provide an explicit, contractual guarantee: Customer Data uploaded to Zunn Legally, Zunn Fihi, or Zunn Sono is never used to train, fine-tune, or improve global foundation models.

Model inference runs in ephemeral memory instances. Once an embedding is generated or a tax computation is resolved, the working context is purged.

4. Ethical Walls & In-Flight PII Redaction

In Zunn Legally, chambers can configure ethical walls that restrict specific matter files to designated counsel teams, preventing internal conflicts of interest.

Before any data is processed for retrieval or analytics, our in-flight PII sanitization engine redacts Tax Identification Numbers (TIN), Business Identification Numbers (BIN), National ID (NID) numbers, bank accounts, and credit card credentials.

5. Governance & Bangladesh Data Residency

All engineering controls are architected in alignment with ISO/IEC 27001 principles, SOC 2 Type II trust criteria, and Bangladesh statutory data protection guidelines.

For financial institutions and government organizations requiring sovereign data sovereignty, Zunn provides on-premises and local cloud deployment topologies within Bangladesh.