Zero-Trust Architecture

QBITEL Bridge implements a zero-trust security model: never trust, always verify. Every request is authenticated, authorized, and encrypted regardless of network location.

Core Principles

  • Verify explicitly -- authenticate and authorize every request based on all available data points
  • Least privilege access -- limit access to the minimum required for each task
  • Assume breach -- minimize blast radius and segment access; verify end-to-end encryption
  • Continuous verification -- re-evaluate trust continuously, not just at session start

Identity-Based Access

Every entity in QBITEL Bridge has a cryptographic identity:

Entity Identity Mechanism Verification
Users JWT / OIDC tokens IdP verification + RBAC
Services mTLS certificates CA chain validation
Devices X.509 + TPM attestation Certificate + hardware binding
API Clients API keys with scopes Key validation + rate limiting

Network Microsegmentation

Network policies restrict pod-to-pod communication to only authorized paths:

# Example: AI Engine can only communicate with
# the control plane and database pods
apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: ai-engine-policy
  namespace: qbitel-service-mesh
spec:
  podSelector:
    matchLabels:
      app: qbitel-engine
  policyTypes:
    - Ingress
    - Egress
  ingress:
    - from:
        - podSelector:
            matchLabels:
              app: controlplane
      ports:
        - port: 8000
  egress:
    - to:
        - podSelector:
            matchLabels:
              app: postgres
      ports:
        - port: 5432

Service Mesh mTLS

All inter-service communication is encrypted with mutual TLS via the Istio service mesh:

  • Automatic mTLS -- Istio sidecar proxies handle certificate management
  • PQC certificates -- quantum-safe certificate rotation via the QKD Certificate Manager
  • Certificate rotation -- automatic rotation with configurable intervals
  • STRICT mode -- reject any plaintext connections

OPA Policy Authorization

The Go control plane uses Open Policy Agent (OPA) for fine-grained authorization decisions:

  • Request-level authorization based on identity, action, and resource
  • Admission control for Kubernetes pod deployments
  • Compliance policy enforcement (e.g., require encryption, restrict data access)
  • Audit logging of all policy decisions

Secrets Management

Secrets are managed through HashiCorp Vault with the following practices:

  • Dynamic secrets -- short-lived credentials generated on demand
  • Automatic rotation -- API keys and certificates rotate on schedule
  • Transit encryption -- encrypt/decrypt without exposing raw keys
  • Audit logging -- every secret access is logged
  • TPM sealing -- edge device secrets sealed to hardware

Admission Control

The Kubernetes admission webhook validates all deployments before they are admitted to the cluster:

  • Reject privileged containers
  • Require resource limits on all pods
  • Enforce security context constraints
  • Validate image signatures and provenance
  • Check for known vulnerabilities in container images

Zero-Touch Security Response

The Zero-Touch Decision Engine provides autonomous threat response within the zero-trust framework:

  • Automatic network isolation of compromised workloads
  • Certificate revocation for compromised identities
  • Dynamic policy updates in response to detected threats
  • Human escalation for high-risk decisions

Next Steps