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Industrial Cybersecurity

OT & ICS Security for Critical Infrastructure

A specialised methodology to secure Operational Technology and industrial IoT without disrupting critical production. Safety and availability come first — every control is adapted to plant constraints, maintenance windows and legacy assets.

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Why OT is different

Security controls must protect safety and uptime first

In enterprise IT the priority order is confidentiality, integrity, availability. In OT it inverts — an unsafe process state or an unplanned shutdown is the real loss event.

Enterprise IT priorities

1
ConfidentialityProtect business data and user access
2
IntegrityMaintain trusted systems and records
3
AvailabilityRestore service within defined SLAs

Operational Technology priorities

1
SafetyAvoid unsafe process states
2
AvailabilityKeep production and critical services running
3
IntegrityPreserve trustworthy control instructions
Our methodology

Four stages, none of which disrupt production

1 · ICS asset discovery

Non-intrusive, passive discovery that builds the inventory you cannot secure without.

  • Passive asset inventory
  • Industrial protocol visibility
  • Communication baseline

2 · OT risk & vulnerability assessment

A safe testing approach designed around plant reality.

  • No disruption to production
  • Maintenance window planning
  • Compensating controls for unpatchable systems

3 · Architecture & segmentation

Purdue-aligned zones and conduits that contain an incident instead of letting it spread.

  • Purdue model zoning and IT/OT DMZ
  • Firewall rule review
  • Secure remote access — jump server, PAM, MFA
  • Vendor access governance

4 · Monitoring & IR readiness

Detection tuned for control networks, integrated with your SOC.

  • OT protocol monitoring and anomaly detection
  • Unauthorised command detection
  • Lateral movement detection
  • Integration with SIEM / XDR / SOC
Attack paths

Where OT attacks usually enter

We prioritise the paths that can bridge enterprise systems and production networks — because those are the ones that end in downtime.

Remote access

Unmanaged or shared remote paths into control networks.

Vendor laptop

Third-party engineering devices connected directly to plant assets.

Enterprise malware

IT-side compromise that pivots across a weak IT/OT boundary.

Engineering workstation

High-privilege hosts able to change control logic.

Flat OT network

No segmentation, so one foothold reaches everything.

Typical outcomes when these are left open: unauthorised change, HMI lockout, historian loss, safety review delay, or full plant shutdown.

Incident response for OT / ICS

Response designed around the plant, not the datacentre

1

Safety first

No response action is taken that could create an unsafe process state.

2

Plant operations coordination

Actions are agreed with operations and engineering before execution.

3

Manual fallback procedure

Documented fallback so production can continue during containment.

4

Forensic evidence preservation

Evidence captured for root cause and regulatory reporting.

5

Staged recovery

Controlled restart with verification at each zone.

Sectors we protect
Utilities & EnergyManufacturingTransport & LogisticsCritical Infrastructure (CII)
FAQ

Frequently asked questions

Will an OT security assessment disrupt our production?

No. Discovery is passive and non-intrusive — we observe traffic rather than scan control devices. Any active testing is scoped with your team and scheduled inside agreed maintenance windows, with compensating controls proposed for systems that cannot be patched.

Do you follow IEC 62443 and the Purdue model?

Yes. Our segmentation and architecture work is aligned to the Purdue reference model with zones and conduits, and assessments map to IEC 62443 practices alongside CII regulatory expectations.

Can you secure legacy PLCs and systems that cannot be patched?

Yes. Where patching is not possible we design compensating controls — network segmentation, protocol allow-listing, strict remote access control and targeted monitoring — so the asset is protected without touching the control logic.

How do you handle vendor and third-party remote access?

Through governed access paths: jump servers, privileged access management, multi-factor authentication, session recording and time-bound approvals, so vendor connections are controlled and auditable.

Talk to our security team

Tell us about your environment — we will come back within one business day with a practical next step.

Contact us → 24×7 Hotline: +65 9091 9188
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