Enterprise Authentication Architecture:
Building for Scale

Enterprise authentication demands more than fast cryptography. It requires high availability, global distribution, compliance controls, and seamless integration with existing infrastructure. This guide covers architectural patterns for deploying H33 at enterprise scale.

Reference Architecture

                    ┌─────────────────────┐
                    │   Global Load       │
                    │   Balancer (DNS)    │
                    └──────────┬──────────┘
           ┌───────────────────┼───────────────────┐
           ▼                   ▼                   ▼
    ┌─────────────┐     ┌─────────────┐     ┌─────────────┐
    │  US-EAST    │     │  EU-WEST    │     │  AP-SOUTH   │
    │  Region     │     │  Region     │     │  Region     │
    └──────┬──────┘     └──────┬──────┘     └──────┬──────┘
           │                   │                   │
    ┌──────┴──────┐     ┌──────┴──────┐     ┌──────┴──────┐
    │ H33 Cluster │     │ H33 Cluster │     │ H33 Cluster │
    │ (3+ nodes)  │     │ (3+ nodes)  │     │ (3+ nodes)  │
    └──────┬──────┘     └──────┴──────┘     └──────┬──────┘
           │                   │                   │
    ┌──────┴──────┐     ┌──────┴──────┐     ┌──────┴──────┐
    │   Redis     │◄────┤   Redis     │────►│   Redis     │
    │   Cluster   │     │   Primary   │     │   Cluster   │
    └─────────────┘     └─────────────┘     └─────────────┘

High Availability Design

Node-Level Redundancy

Each region runs a minimum of 3 H33 nodes behind a load balancer:

• Health checks: 1-second intervals, 3 failures to remove
• Graceful shutdown: Drain connections before termination
• Rolling updates: One node at a time, zero-downtime deploys

Regional Failover

DNS-based failover routes traffic away from unhealthy regions:

• Active-active: All regions serve traffic simultaneously
• Latency-based routing: Users route to nearest healthy region
• Automatic failover: Unhealthy regions removed within 30 seconds

Session State Management

H33's 50µs session resume requires distributed session state:

// Session configuration for multi-region
const sessionConfig = {
  store: 'redis-cluster',
  replication: {
    mode: 'async',           // Async for performance
    regions: ['us-east', 'eu-west', 'ap-south'],
    consistencyLevel: 'eventual'  // Strong consistency optional
  },
  encryption: {
    atRest: true,
    algorithm: 'aes-256-gcm'
  }
};

Cache Consistency

The 67x proof cache speedup requires careful cache invalidation:

• Local cache: Each node caches recent proofs in-memory
• Distributed cache: Redis stores proofs for cross-node access
• Invalidation: Pub/sub broadcasts cache invalidations

Compliance Considerations

Data Residency

For GDPR, CCPA, and other regulations:

• Biometric data never leaves origin region
• ZK proofs contain no personal data (by design)
• Session tokens can be region-locked
• Audit logs stored per-region with configurable retention

Audit Logging

Every authentication event is logged:

{
  "timestamp": "2026-01-29T10:15:32.267Z",
  "eventType": "auth.fullstack.success",
  "userId": "user_xxx",  // Hashed
  "latencyUs": 218,
  "region": "us-east-1",
  "mode": "turbo",
  "proofId": "proof_xxx",
  "deviceFingerprint": "fp_xxx"  // Hashed
}

Integration Patterns

Identity Provider Integration

H33 complements existing IdPs:

// SAML integration
app.post('/saml/callback', async (req, res) => {
  const samlAssertion = await validateSAML(req.body);

  // Enhance with H33 biometric + ZK proof
  const h33Result = await h33.auth.enhance({
    existingIdentity: samlAssertion.nameId,
    biometric: req.body.biometric,
    mode: 'turbo'
  });

  // Combined session with ZK attestation
  req.session.identity = {
    saml: samlAssertion,
    h33Proof: h33Result.proof
  };
});

API Gateway Integration

Validate H33 tokens at the API gateway:

# Kong/nginx configuration
location /api/ {
  auth_request /h33-validate;
  auth_request_set $h33_user $upstream_http_x_h33_user;
  proxy_set_header X-User $h33_user;
  proxy_pass http://backend;
}

location = /h33-validate {
  internal;
  proxy_pass http://h33-cluster/validate;
  proxy_pass_request_body off;
  proxy_set_header Content-Length "";
  proxy_set_header X-H33-Token $http_authorization;
}

Monitoring and Observability

Key Metrics

• auth.latency.p50/p99: Authentication latency percentiles
• auth.throughput: Authentications per second
• cache.hit_rate: Proof cache effectiveness
• session.resume_rate: Percentage using fast resume path
• error.rate: Failed authentications

Alerting Thresholds

• p99 latency > 1ms: Warning (something is degraded)
• p99 latency > 5ms: Critical (investigate immediately)
• Error rate > 0.1%: Warning
• Error rate > 1%: Critical
• Cache hit rate < 80%: Warning (cache may be undersized)

Capacity Planning

Given H33's high-throughput per node, capacity planning focuses on other bottlenecks:

• Network: Each auth request is ~2KB, response ~1KB
• Memory: ~3GB per node for 10K concurrent sessions
• Redis: 100MB per 100K cached proofs

For 1M daily active users with 10 auth events per user per day:

• Peak load estimate: ~2,000 auth/second (morning spike)
• Required H33 nodes: 1 (with 4,000x headroom)
• Recommended: 3 nodes for HA (still 1,400x headroom each)