Cybersecurity
Network Segmentation
Separating the control network from everything else.
Written guides in this section
Full references, procedures, and diagnostic guides published under Network Segmentation.
Zones and Conduits
The IEC 62443 way to segment a control system: grouping assets into zones with a shared security level, inventorying every conduit between them, and turning the drawing into firewall rules. With a worked water utility example.
12 min readUpdated Sep 5, 2026
VLAN Segmentation
Using VLANs to build the zones of a control network on shared switches: what a VLAN separates and what it does not, the zone-to-VLAN mapping, trunks and the native VLAN, routing only through a firewall, and where separate hardware begins.
9 min readUpdated Sep 5, 2026
Industrial DMZ Design
The buffer zone between the business network and the control system: what goes in it, the no-direct-path rule, push-not-pull data flows, the firewall pair, and the services a utility actually needs to place there.
10 min readUpdated Sep 5, 2026
Data Diodes
Hardware that lets data flow one way only, from the control network outward, with no physical return path: what a data diode and a unidirectional gateway are, where they belong, what they can and cannot carry, and when a firewall is enough instead.
8 min readUpdated Sep 5, 2026
Segmenting a Remote Site
A lift station, a well, or a tank site as its own zone: the site firewall and what it permits, the modem as transport with no public address, cameras and extras off the control segment, engineering access through the plant, and local control without the link.
9 min readUpdated Sep 5, 2026
Topics in this area
Zones and Conduits
Zones and Conduits — practical reference notes for controls engineers, integrators, and technicians working with network segmentation.
VLAN Segmentation
VLAN Segmentation — practical reference notes for controls engineers, integrators, and technicians working with network segmentation.
DMZ Design
DMZ Design — practical reference notes for controls engineers, integrators, and technicians working with network segmentation.
Data Diodes
Data Diodes — practical reference notes for controls engineers, integrators, and technicians working with network segmentation.
Segmenting A Remote Site
Segmenting A Remote Site — practical reference notes for controls engineers, integrators, and technicians working with network segmentation.
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