Purdue model
- Orders systems by function: from the process (L0) to the business (L5).
- L3.5 is the intermediate zone between IT and OT.
- It says what a system does, not how to protect it.
We bridge IT and OT by designing and implementing secure, scalable network architectures for industrial sites and critical infrastructure.
We build on IEC 62443, NIS2 and automation. The result: an incident does not stop production, supplier access stays under control, and compliance can be proven.
External
IT
Industrial DMZ
OT
A short note on what each one brings to the design.
From current-state assessment to deployment and operations — one consistent technical and operating model.
IT
OT
We inventory assets and flows and assess risks and threat scenarios against IEC 62443 and NIS2, turn the findings into priorities and an actionable roadmap, and prepare evidence for NIS2 audits.
We are the bridge between IT and OT. We combine data confidentiality with process continuity in one architecture: segmentation, controlled data exchange, secure remote access.
We create shared standards and patterns, and deploy configuration automatically. Every further change and site stays predictable, repeatable and easy to audit.
We deploy at new sites and in legacy installations: in stages, with rollback plans and service testing, without stopping the process.
One controlled service path for suppliers and employees: strong authentication, time-limited access, full accountability. No direct connections to controllers.
Monitoring deployed as code, together with the infrastructure. It shows the business the continuity of key services, detects deviations early and, during an incident, helps isolate a site quickly and restore operations.
Vendor-neutral: we fit the technology to the process, the risk and your existing environment.
Network security
Splitting the network into zones and controlling who may talk to whom
Industrial DMZ
Controlled IT/OT data exchange
Zero Trust and ZTNA
Verified access, no implicit trust
MFA and PAM
Strong authentication, privileged accounts, session recording
Automation and IaC
Standards, templates, repeatable deployments
OT monitoring
Passive visibility, inventory, anomaly detection
Logs and SIEM
IT/OT event correlation, audit evidence
Network and site connectivity
Network design from HQ to every site: stable, redundant and predictable
One standard, many sites, secure scaling. Every new site gets a proven setup: a separated OT network, its own boundary and controlled supplier access.
Remote sites
Every site has its own OT boundary
Remote access
Connectivity
Incident isolation
Separation of duties
Data centre
Trusted and untrusted
Each layer limits the impact of an incident. One pattern for every site.
The most common OT attack scenarios stop at designed boundaries.
No direct path from IT to the process.
Only verified, limited access.
An incident stays in one zone.
The process network has no internet exposure.
A single service connection can open a path into the whole farm. We show how the same service looks when done safely, without getting in the supplier’s way.
Without control
With the Secura-Ops model
Recording · time window
We translate international standards and industry best practices into your organisation’s own standards and documentation — and those into repeatable deployments that can be safely reused at further sites.
Standards
Organisational rules built on norms and best practice.
Source of truth
One approved place for infrastructure data.
IaC
Configuration generated from data and patterns.
Deployment
Staged, tested and reversible.
Compliance
Continuous check that the network matches the design.
We start with what delivers the quickest results and grow the model at your organisation’s pace.
Starting point
OutcomeReport with priorities and roadmap
Target architecture
OutcomeApproved pattern for all sites
Staged change
OutcomeWorking, tested sites
Continuous control
OutcomeContinuous control and audit evidence
Not sure where to start? We start with an assessment.
Excerpts from our IT/OT reference model.
Standards and automation
Shared rules for names, addresses and access are the foundation. Only on top of them does automation deliver repeatable, secure deployments.
Industrial DMZ
An IT DMZ protects the company from the internet. An OT DMZ protects the process from the corporate network, because most attacks on OT start in IT.
OT monitoring
Segmentation limits an incident, monitoring detects it. Near controllers, observe only — no active scanning.
NIS2 and compliance
An auditor does not ask whether you have a firewall. They ask whether you can prove that risk is managed and controls work.
Remote access
A supplier reaches the plant only through a controlled access point, never directly to controllers. Every connection requires MFA, has a time window and is recorded.
Multi-site
Every site has its own independent security boundary, so an incident at HQ or one farm does not spread to the others.
We fit the model to the process and the risk, not the industry label.
We work where downtime means no energy, heat or water, or a stopped production line. Shared needs: resilience, control over supplier access and NIS2 compliance.
About us
We specialise in IT/OT network security and its automation, with hands-on experience in energy, industry and critical infrastructure. We work with automation teams, because in OT a safeguard that stops the process is a failure, not protection.
Jarosław Dolinny
IT/OT Network Security Architect
Energy and industry
Industries we have hands-on experience in.
Critical infrastructure
Sites where continuity matters most.
From design to operations
Architecture, deployment and automation.
Multi-site environments
Farms, plants and data centres in one model.
A short call is enough to set priorities and the first step.