Control for OT environments

Physical network governance for operational technology.

Industrial control systems, SCADA networks and manufacturing processes were built for reliability, not cybersecurity. As IT/OT convergence accelerates, these systems face threats they were never designed to withstand.

• IT/OT convergence
• Legacy systems
• Configuration tampering

The scenario

Scenario: ransomware crosses IT into OT.

A firewall between IT and OT looked like an air gap. A firewall rule is software, and software can be bypassed. Step through it, or play it through.

1. 01The attack path
2. 02With Control

Step 1 of 2

The attack path

A manufacturing plant’s IT network is compromised through a phishing email targeting the finance team, and the ransomware spreads across the corporate network within four hours.

Because the historian server bridges IT and OT, the ransomware reaches the OT network by hour six. PLC configurations are encrypted, SCADA displays go dark, and recovery takes 18 days because backup PLC configurations were on a network share, also encrypted.

The path

Always there

What the attacker needs

A foothold and time

Play it through

An illustrative scenario.

Layer 1

Separation of IT from OT

24/7

Operational continuity maintained

9

Governance modules for OT isolation

Logged

Evidence for IEC 62443 zones and conduits

Where each Control module is deployed across the Purdue layers.

Most OT estates still look like a stack: enterprise on top, an industrial DMZ in the middle, process control and supervisory layers below it, and safety at the bottom. Control puts a physical boundary at every step, so a problem at one layer does not propagate to the next.

1. At every Purdue boundaryIsolateEach layer sits on its own physical fabric.
2. L5 to L4 and L4 to L3.5 linksFirebreakA physical cut for the OT team on the IT boundary.
3. Inside the L3.5 DMZRelayData moves from enterprise into OT through scheduled, defined routes.
4. Inside the L3.5 DMZValidateBefore anything reaches process control, Validate checks its origin, integrity and authority.
5. Inside the L3.5 DMZTransferWhen data has to move across the boundary, Transfer governs how it crosses and where it lands.
6. L2 to L1 linkExecutePushing a change to a controller holds until the right approval is in place.
7. L1 to SIS and SIS to L0 linksLockSafety is the last layer anything reaches.

Explore the Control Blueprints

From first boundary to routine operation.

Four steps, piloted on one site before it extends across the estate.

1. 1

   OT environment audit

   Map all IT/OT boundaries, shared network paths, historian connections and remote access points.

2. 2

   Zone and conduit design

   Align Control modules to IEC 62443 security zones and conduits, designing physical separation.

3. 3

   Non-disruptive pilot

   Deploy alongside existing PLCs, SCADA systems and RTUs, without changes to operational equipment.

4. 4

   Production go-live

   Activate controlled maintenance windows, historian backup replication and tamper-evident audit trails.

Explore more

Where to go next.

• Critical infrastructure
• IT/OT convergence
• CP-05 Protect Critical Infrastructure
• OT recovery
• Control Blueprints
• Control by industry

• Isolate
• Firebreak
• Relay
• Validate
• Transfer

Speak to the team to organise a PoC.

Walk through your blueprint with the Firevault team and scope a proof of concept on your estate. 30 minutes, no sales pitch.