Cybersecurity
OT Security
The fundamentals that everything else rests on.
Written guides in this section
Full references, procedures, and diagnostic guides published under OT Security.
IEC 62443
The international standard series for industrial automation and control system security: how it is organized, what security levels and foundational requirements mean, and how a utility or integrator actually uses it.
11 min readUpdated Sep 5, 2026
OT Risk Assessment
Ranking what could go wrong in a control system and what it would cost: the consequence-first method for utilities, the assets and scenarios to list, likelihood without pretending to know it, the risk matrix, and turning the ranked list into a work plan.
10 min readUpdated Sep 5, 2026
Security Program Basics
What a control system security program is for a utility that has never had one: a named owner, an inventory, a risk assessment, a few policies, baseline controls, training, vendor rules, an exercised incident plan, and a first-year plan for a small staff.
10 min readUpdated Sep 5, 2026
OT Security vs IT Security
Why the familiar security priorities invert on a plant floor, and what that changes about patching, scanning, authentication, and incident response.
8 min readUpdated Aug 26, 2026
The Purdue Model
The reference architecture most segmentation designs still start from: what each level contains, where the DMZ goes, and how it maps to a water utility.
8 min readUpdated Aug 20, 2026
Topics in this area
OT vs IT Security
Why availability and safety outrank confidentiality on a plant floor, and what that changes.
Purdue Model
The reference architecture that most segmentation designs still start from.
IEC 62443
IEC 62443 — practical reference notes for controls engineers, integrators, and technicians working with ot security.
Risk Assessment
Risk Assessment — practical reference notes for controls engineers, integrators, and technicians working with ot security.
Security Program Basics
Security Program Basics — practical reference notes for controls engineers, integrators, and technicians working with ot security.
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