IoT Security

IoT PKI Solution: Complete Guide to Securing Connected Devices

Learn how to implement PKI security solutions for IoT devices at scale, including device identity, certificate provisioning, and lifecycle management.

R
Robert Williams
Chief Security Officer
2026-02-06
14 min read

The IoT Security Challenge

The Internet of Things (IoT) is transforming industries, with billions of connected devices deployed across manufacturing, healthcare, transportation, and smart infrastructure. However, this connectivity explosion creates massive security challenges:

  • Device Identity: How do you verify a device is legitimate?
  • Communication Security: How do you encrypt device-to-cloud traffic?
  • Credential Management: How do you manage certificates on millions of devices?
  • Lifecycle Security: How do you update and rotate credentials over time?

PKI (Public Key Infrastructure) provides the foundation for addressing these challenges at scale.

Why PKI for IoT?

The Limitations of Passwords and API Keys

Traditional authentication methods fail at IoT scale:

Passwords:

  • Can't be unique per device at scale
  • Vulnerable to brute force attacks
  • Difficult to rotate
  • Not suitable for device-to-device auth

API Keys:

  • Often shared across devices
  • Difficult to revoke individually
  • No device identity verification
  • Limited cryptographic security

PKI Advantages for IoT

PKI-based security provides:

┌─────────────────────────────────────────────────────────────┐
│                    IoT PKI Benefits                         │
├─────────────────────────────────────────────────────────────┤
│ ✓ Unique identity per device                                │
│ ✓ Strong cryptographic authentication                       │
│ ✓ Encrypted communications (TLS/DTLS)                      │
│ ✓ Scalable to billions of devices                          │
│ ✓ Individual device revocation                              │
│ ✓ Automated certificate lifecycle                           │
│ ✓ Standards-based interoperability                         │
└─────────────────────────────────────────────────────────────┘

IoT PKI Architecture

Components

A comprehensive IoT PKI solution includes:

Certificate Authority (CA):

  • Root CA (offline, highest security)
  • Issuing CA (online, device certificate issuance)
  • Registration Authority (device enrollment validation)

Device Identity:

  • Device certificates (unique per device)
  • Hardware security (TPM, secure element)
  • Device provisioning infrastructure

Management Platform:

  • Certificate lifecycle management
  • Monitoring and alerting
  • Policy enforcement
  • Audit and compliance

Architecture Diagram

                    ┌──────────────────┐
                    │   TigerTrust     │
                    │   PKI Platform   │
                    └────────┬─────────┘
                             │
        ┌────────────────────┼────────────────────┐
        ▼                    ▼                    ▼
 ┌──────────────┐   ┌──────────────┐   ┌──────────────┐
 │   Root CA    │   │ Issuing CA   │   │  OCSP/CRL    │
 │  (Offline)   │   │  (Online)    │   │  Responder   │
 └──────────────┘   └──────────────┘   └──────────────┘
                             │
        ┌────────────────────┼────────────────────┐
        ▼                    ▼                    ▼
 ┌──────────────┐   ┌──────────────┐   ┌──────────────┐
 │  IoT Cloud   │   │ Edge Gateway │   │   Device     │
 │  Platform    │   │              │   │ Provisioning │
 └──────────────┘   └──────────────┘   └──────────────┘
        │                    │                    │
        ▼                    ▼                    ▼
 ┌──────────────────────────────────────────────────────┐
 │                    IoT Devices                        │
 │   [📱] [🔌] [🏭] [🚗] [🏥] [📷] [🌡️] [💡]            │
 └──────────────────────────────────────────────────────┘

Device Identity and Provisioning

Device Certificate Types

Different IoT use cases require different certificate approaches:

1. Manufacturer-Provisioned Certificates

Certificates embedded during manufacturing:

  • IDevID (IEEE 802.1AR) - immutable device identity
  • Provisioned in secure element or TPM
  • Used for initial device authentication

2. Operational Certificates (LDevID)

Certificates issued after deployment:

  • Organization-specific identity
  • Used for ongoing operations
  • Renewable and rotatable

3. Application Certificates

Purpose-specific certificates:

  • TLS client/server certificates
  • Code signing certificates
  • Data encryption certificates

Secure Device Provisioning

# TigerTrust IoT device provisioning example import tigertrust client = tigertrust.IoTClient( api_key="your-api-key", device_group="manufacturing-sensors" ) # Provision a new device device = client.devices.provision( device_id="sensor-001", device_type="temperature-sensor", hardware_attestation={ "tpm_endorsement_key": "...", "platform_certificate": "..." } ) # Issue device certificate cert = client.certificates.issue( device_id=device.id, subject="CN=sensor-001.example.com,O=ACME Corp", validity_days=365, key_type="ECDSA-P256" ) print(f"Certificate issued: {cert.serial_number}")

Hardware Security Integration

Secure device identity requires hardware security:

TPM (Trusted Platform Module):

  • Secure key storage
  • Hardware attestation
  • Tamper resistance

Secure Elements:

  • Dedicated crypto processor
  • Protected key material
  • Certified security (CC EAL4+)

HSM Integration:

  • Central key protection
  • High-speed crypto operations
  • Regulatory compliance

Certificate Lifecycle for IoT

Issuance at Scale

IoT deployments require high-volume certificate issuance:

TigerTrust IoT Issuance Capacity:

Standard:    10,000 certificates/hour
Enterprise:  100,000 certificates/hour
Scale:       1,000,000+ certificates/hour

Automated Renewal

For millions of devices, manual renewal is impossible:

# TigerTrust IoT renewal policy policy: name: iot-device-renewal device_groups: - manufacturing-sensors - medical-devices - smart-meters renewal: trigger_days_before_expiry: 30 method: automatic require_attestation: true rollback_on_failure: true deployment: method: push channels: - mqtt - https retry_attempts: 3 confirmation_required: true

Revocation

Immediate device revocation capabilities:

# Revoke a compromised device tigertrust iot revoke \ --device-id sensor-001 \ --reason "key_compromise" \ --effective "immediate" # Bulk revocation for device group tigertrust iot revoke-group \ --group "recalled-devices" \ --reason "affiliation_changed"

IoT Communication Security

TLS for IoT

Secure device-to-cloud communication:

Standard TLS (1.3):

  • Full-featured devices
  • Adequate processing power
  • Reliable connectivity

DTLS (Datagram TLS):

  • UDP-based IoT protocols
  • Constrained networks
  • CoAP communication

Mutual TLS (mTLS)

Both device and server authenticate:

Device → Server: Present device certificate
Server → Device: Verify device identity
Server → Device: Present server certificate
Device → Server: Verify server identity
Both: Establish encrypted channel

Benefits:

  • Device authentication
  • Server authentication
  • Encrypted communication
  • Protection against MITM attacks

IoT PKI Use Cases

Industrial IoT (IIoT)

Manufacturing and industrial automation:

  • Factory Equipment: Secure machine-to-machine communication
  • SCADA/ICS: Critical infrastructure protection
  • Supply Chain: Device authenticity verification

Healthcare IoT

Medical device security:

  • Patient Monitors: Secure health data transmission
  • Infusion Pumps: Command authentication
  • Medical Imaging: Secure image transfer

Automotive IoT

Connected vehicle security:

  • V2X Communication: Vehicle-to-everything security
  • OTA Updates: Authenticated firmware updates
  • Telematics: Secure data collection

Smart Infrastructure

Utilities and smart cities:

  • Smart Meters: Secure utility communication
  • Grid Devices: Energy infrastructure security
  • Traffic Systems: Transportation safety

TigerTrust IoT PKI Solution

Comprehensive Platform

TigerTrust provides enterprise IoT PKI:

PKI Core for IoT:

  • Dedicated IoT CA hierarchy
  • High-volume issuance engine
  • HSM protection for CA keys
  • CRL/OCSP infrastructure

Device Identity Management:

  • Device enrollment and provisioning
  • Hardware attestation integration
  • Device group management
  • Lifecycle tracking

Certificate Automation:

  • Automated issuance and renewal
  • Push-based certificate deployment
  • Protocol support (MQTT, HTTPS, EST)
  • Failure handling and rollback

Monitoring & Compliance:

  • Real-time device status
  • Certificate health monitoring
  • Compliance reporting
  • Audit logging

Integration Capabilities

┌─────────────────────────────────────────────────────────────┐
│              TigerTrust IoT Integrations                    │
├─────────────────────────────────────────────────────────────┤
│ Cloud Platforms:    AWS IoT, Azure IoT Hub, Google Cloud   │
│ IoT Protocols:      MQTT, CoAP, AMQP, HTTP/HTTPS           │
│ Provisioning:       EST, SCEP, Custom APIs                 │
│ Hardware:           TPM 2.0, Secure Elements, HSMs         │
│ Device Platforms:   Linux, RTOS, Embedded                  │
└─────────────────────────────────────────────────────────────┘

Deployment Options

  • Cloud SaaS: Managed PKI for IoT
  • On-Premise: Full control in your data center
  • Hybrid: Edge-cloud combination
  • Air-Gapped: Isolated manufacturing environments

Implementation Best Practices

Security First

  1. Use hardware security where possible (TPM, secure elements)
  2. Unique identity per device - never share certificates
  3. Short-lived certificates - reduce exposure window
  4. Automated rotation - eliminate manual processes

Scale Considerations

  1. Design for millions - not hundreds
  2. Asynchronous provisioning - handle network unreliability
  3. Edge caching - reduce central CA load
  4. Monitoring at scale - automated anomaly detection

Lifecycle Planning

  1. Secure manufacturing - inject identity early
  2. Field provisioning - handle post-deployment enrollment
  3. Renewal automation - continuous lifecycle management
  4. End-of-life - proper decommissioning and revocation

Getting Started

Step 1: Assess Your IoT Environment

  • How many devices do you have/plan?
  • What protocols do devices use?
  • What security hardware is available?
  • What are your compliance requirements?

Step 2: Design Your IoT PKI

  • CA hierarchy for IoT
  • Certificate policies
  • Provisioning workflows
  • Renewal automation

Step 3: Pilot Deployment

  • Start with device subset
  • Validate provisioning flow
  • Test renewal automation
  • Verify revocation

Step 4: Scale Rollout

  • Gradual device migration
  • Manufacturing integration
  • Monitoring implementation
  • Team training

Conclusion

IoT security at scale requires purpose-built PKI solutions. Traditional certificate management approaches cannot handle the volume, variety, and lifecycle requirements of IoT deployments.

TigerTrust's IoT PKI solution provides the enterprise-grade capabilities needed for securing millions of connected devices—from device identity provisioning through complete certificate lifecycle automation.

Secure your IoT infrastructure today. Start your free trial or talk to our IoT security team.

TOPICS

iot pki solution
iot security
device identity
certificate management
enterprise pki management
pki security solutions for the enterprise

SHARE THIS ARTICLE

Ready to Transform Your Certificate Management?

See how TigerTrust can help you automate certificate lifecycle management at scale.