ICS/OT cybersecurity

ICS/OT Cybersecurity Solutions Implementation

Design, deployment and tuning of OT security technology, from the firewall to the SOC.

Best forOrganizations deploying OT security technology, or setting up OT monitoring and a SOC.

Service overview

The right technology for your environment, not ours

Our engineers support the selection and deployment of technologies to detect, prevent, and respond to threats. We ensure seamless deployment without disrupting critical industrial processes. We are vendor-agnostic and work with top providers to find the right fit for your architecture.

We have no vendor affiliation and receive no referral fees. Our technology recommendations are driven entirely by what fits your industrial protocols, your network topology, your existing infrastructure, and your operational constraints.

Every implementation includes commissioning in a staging or test environment before production deployment, and a documented handover package that enables your team to operate the technology independently after the engagement closes.

Technology only helps when someone acts on what it reports. So we also connect it to your SOC: OT use cases, detection rules, triage steps and playbooks that your analysts and your control room both understand.

Technology domains

Seven domains, from the firewall to the SOC

Six defence families, placed where they sit on the Purdue model and rated by how much each one matters, plus the SOC that turns their alerts into action. Logos show technology we work with, not endorsements.

Network ProtectionIndustrial firewalls & segmentation

Where it sits

Perimeter firewalls either side of the DMZ · segmentation at L3 and L2

CriticalityCritical

Zone-and-conduit segmentation with firewalls that understand Modbus, DNP3 and OPC UA. Nothing in the plant is reachable from the internet, and the plant keeps running when the corporate network does not.

What we deliver

Zone and conduit design, with a rule for every conduit and nothing else allowed
Firewalls either side of the DMZ and segmentation inside L3 and L2
Rule review and change process, so the rules stay right after we leave

Maps toIEC 62443-3-2 zones & conduits · IEC 62443-3-3 SR 5.1 · NIST 800-82 network architecture

Secure Remote AccessBrokered, recorded vendor sessions

Where it sits

L3.5 DMZ jump host

CriticalityCritical

Replaces always-on VPN tunnels and shared logins with brokered, MFA-gated, time-boxed sessions that are recorded end to end and can be cut by the control room at any moment.

What we deliver

Jump host in the DMZ, with no direct vendor tunnels into L3 or L2
MFA, time-boxed approval and full session recording
Vendor on-boarding, access reviews and a kill switch for the control room

Maps toIEC 62443-3-3 SR 1.1 / 1.13 · IEC 62443-2-4 · NCA OTCC 2-2 / 2-4

Backup & RecoveryController, HMI & server resilience

Where it sits

L1 – L3, offline copies

CriticalityCritical

Automated, offline-capable backups of PLC logic, HMI projects, historians and the servers the line depends on, with restore drills rehearsed before the incident rather than during it.

What we deliver

Automated backups of PLC logic, HMI projects, historians and servers
Offline copies kept out of reach of ransomware
Timed restore drills, so you know your real recovery time

Maps toIEC 62443-3-3 SR 7.3 / 7.4 · NIST CSF Recover · NIS2 Art. 21(2)(c) · NCA OTCC 2-8

OT IDS / MonitoringPassive visibility & threat detection

Where it sits

L2 · L3 (passive SPAN taps)

CriticalityImportant

Passive sensors that inventory every asset and inspect industrial protocols, so an unexpected Modbus write or a new device on the control network raises an alert within minutes, not months.

What we deliver

Sensor placement and SPAN or TAP design for every zone that matters
Asset inventory built from real traffic, not from a spreadsheet
Baseline of normal operation and alerts tuned against it

Maps toIEC 62443-3-3 SR 6.2 · NIS2 Art. 21 · NCA OTCC 2-11

Endpoint ProtectionHMI & engineering workstation hardening

Where it sits

L2 · L3 Windows hosts

CriticalityImportant

Application allow-listing and OT-aware antivirus on HMIs, historians and engineering stations, plus portable scanners for air-gapped machines. Malware that cannot execute cannot spread.

What we deliver

Application allow-listing on HMIs, historians and engineering stations
Patch and antivirus updates staged through the DMZ
Portable scanning for air-gapped and vendor-supplied machines

Maps toIEC 62443-3-3 SR 3.2 · IEC 62443-2-1 (malware protection) · NIST 800-82 host security

Specialized DefenseData diodes, USB kiosks & OT honeypots

Where it sits

Diode L3/L3.5 (OT → IT) · USB kiosk L2 · honeypots as SIS, DCS, IED

CriticalityTargeted

Unidirectional gateways for outbound historian and monitoring traffic, USB scanning kiosks as the single sanctioned path for removable media at Level 2, and decoy SIS, DCS and IED nodes that no legitimate user ever touches, so the first hop of an intrusion is the one that gets caught.

What we deliver

Data diodes for historian and monitoring traffic leaving OT for IT
USB scanning kiosk as the only route for removable media to Level 2
Honeypots that look like an SIS, DCS or IED, wired to your alerting

USB scanning kioskOT honeypots

Maps toIEC 62443-3-3 SR 5.2 · IEC 62443-3-3 SR 2.3 (portable media) · IEC 61511 SIS separation

OT SOCUse cases, detection rules and playbooks

Where it sits

Above the stack. Takes alerts and logs from every domain on this page.

Monitoring only lowers risk when someone reads the alerts and knows what to do next. We connect every domain above to your SOC or SIEM and write the OT side of it: what to watch for, which alerts matter, how to triage them, and when to call the control room.

What we deliver

Alert and log sources connected from every domain above
OT use case catalogue and detection rules, tuned to how your plant runs
Alert triage steps, with a clear handoff to the control room
Response playbooks for the most likely OT attack scenarios
Advice on building an OT SOC or extending your IT SOC to cover OT

Takes alerts from

Network ProtectionSecure Remote AccessBackup & RecoveryOT IDS / MonitoringEndpoint ProtectionSpecialized Defense

Maps toIEC 62443-3-3 SR 6.1 / 6.2 · NIS2 Art. 21(2)(b) · NCA OTCC 2-11

Our approach

Engagement methodology

The steps of the engagement, designed around the operational constraints of live industrial environments.

Step 01 / 08

Requirements and environment analysis

Document your industrial protocols, asset types, network topology, and operational constraints. Evaluate vendor candidates against these specific requirements rather than generic feature comparisons.

Step 02 / 08

Technology selection

Provide vendor-neutral selection guidance with justification for the recommended platform. Compare shortlisted options against your protocol support requirements, latency constraints, and budget.

Step 03 / 08

Architecture design

Design the implementation architecture including sensor placement, traffic mirror configuration, integration with existing infrastructure, and monitoring coverage across all required zones.

Step 04 / 08

Staging environment deployment

Deploy and configure the technology in a staging or test environment. Validate that it correctly identifies your specific industrial protocols and produces useful, actionable monitoring output.

Step 05 / 08

Production deployment

Execute production deployment during a planned maintenance window. Minimise production impact through pre-configured device images, staged rollout, and immediate rollback capability.

Step 06 / 08

Tuning and optimisation

Tune detection rules and alert thresholds to your specific environment. Reduce false positives against known-good operational behaviour while maintaining sensitivity to genuine anomalies.

Step 07 / 08

SOC integration

Connect alerts and logs to your SOC or SIEM. Define OT-specific use cases, configure detection rules, write alert triage steps with a clear handoff to the control room, and build response playbooks for the most likely OT attack scenarios.

Step 08 / 08

Team handover

Train your team on platform operation, alert triage, and routine maintenance. Deliver full operational documentation including configuration baselines and escalation procedures.

What you receive

Service deliverables

Technology selection report with vendor evaluation and recommendation justification

Implementation architecture design document

Staging environment validation results

Production deployment with configuration baselines

OT SOC use case catalogue and detection rules, tuned to your environment

Alert triage procedures and SOC playbooks for OT attack scenarios

Team training and platform orientation

Full operational documentation and handover package

Post-deployment validation report

IEC 62443NIST 800-82NCA OTCCNIS2

Oil and GasPower GenerationElectric UtilitiesManufacturingChemicalAutomotive

Common questions

Frequently asked questions

Are you tied to any specific vendors?

Which platforms do you deploy?

Can you help us build an OT SOC?

Do we need all seven domains?

Will deployment disrupt our operations?

Do you tune the technology after installation?

What happens after deployment?

Talk to RelyBlue

Ready to discuss ICS/OT Cybersecurity Solutions Implementation?

An honest conversation about your OT environment. No sales pressure, no fear tactics.

You talk to a senior advisor, never a salesperson