What are the best practices for securing IoT devices in critical infrastructure?

IoT devices are increasingly deployed in critical infrastructure, from smart grids to manufacturing control systems. This makes them prime targets for cyberattacks, where even a short disruption can cause significant financial and operational damage. Securing these deployments requires a layered, proactive approach.

Why securing IoT in critical infrastructure is different

Critical infrastructure IoT differs from consumer devices because downtime can disrupt economies, public safety, and essential services. Attacks like the Mirai botnet and ransomware against utilities show the scale of risk. Security must balance uptime, safety, and compliance while protecting against both insider and external threats (ENISA, CISA).

 

Best practices for securing IoT devices in critical infrastructure

 

1. Build an inventory and risk profile

You can’t secure what you don’t know. Start with a complete inventory of all IoT devices, firmware, and connections. Use this to map risks and prioritise remediation (NIST IR 8259A).

 

2. Isolate IoT traffic with private networks

Keeping IoT traffic off the public internet reduces exposure to cyber threats. Private APNs, network slicing, and controlled VPN tunnels provide isolation and compliance. The GSMA IoT Security Guidelines recommend private networking for sensitive deployments.


IXT’s SecureNet enables private, isolated IoT connectivity with built-in VPN options.

 

3. Enforce strong authentication and device identity

Replace default credentials with unique device identities and certificate-based authentication. Role-based access control (RBAC) ensures only authorised personnel and systems can communicate with devices (NIST).

 

4. Encrypt data in transit and at rest

Data moving between IoT devices, gateways, and cloud systems should always be encrypted using TLS 1.2+ or IPSec VPNs. At-rest encryption ensures telemetry and logs remain secure even if compromised.

 

5. Secure device configuration and updates

Devices should run with hardened configurations: secure boot, signed firmware, and locked-down services. Over-the-air (OTA) patching ensures devices remain protected throughout their lifecycle (ENISA IoT Security Best Practices).

 

6. Monitor, detect, and respond in real-time

Continuous monitoring is essential for detecting anomalies, device compromise, or unusual traffic flows. Integrating IoT traffic into a SIEM system or using anomaly detection reduces mean time to detection (CISA ICS Security).

 

7. Apply zero-trust principles

Zero trust means never assuming trust between devices, users, or networks. Verification is required at each step, limiting lateral movement if one system is breached (Forrester Zero Trust Model).

 

How IoT connectivity providers strengthen critical infrastructure security

 

A secure IoT connectivity partner can help enforce many of these practices. For example, IXT combines:

 

 

Protecting IoT in critical infrastructure

Securing IoT devices in critical infrastructure requires layered defences—private networking, encryption, strong authentication, and continuous monitoring. With the right practices, enterprises can protect uptime, data integrity, and public trust.

 

 Explore how IXT SecureNet helps enterprises secure IoT deployments in critical infrastructure.