OT means the plant systems that run the machines, as distinct from office IT. For years, securing those systems lived in policy slide decks. In 2025 and 2026 it shows up in bid requests, insurer questions, and reviews where the customer’s IT team and the plant team sit in the same room. That is healthy if engineering treats it as how the network is built, not as paperwork.
What plants are being asked
- How is the machine, or the cell of machines, separated from the office network?
- Who can reach the programming ports, and how is remote support controlled?
- What is the update and backup plan for operator screens, industrial PCs, and historians? An operator screen is the HMI. An industrial PC is a hardened computer in the cabinet. A historian is the database that stores machine readings over time.
- Are default passwords, and one flat network from the sensors up through the controllers, still the norm? Level 0 to 2 is the usual name for that span: the devices, then the controllers, then the area screens.
What “good enough” looks like for many mid-size plants
Not every plant needs a full ISA/IEC 62443 certificate on day one. That standard is the common industrial-security rulebook. Many plants need a written map of zones and the paths between them, managed switches, a locked-down jump computer or another controlled way in from outside, operator-screen logins that match the person’s job, and a spare or a disk image for the computers that matter. Those basics prevent a large share of the risk that actually stops production.
What this changes in the controls work
Security design affects how the PLC, the machine controller, is networked, how the SCADA screens are placed, how vendors use their remote-access tunnels, and even the panel layout: where the industrial PC sits, how USB ports are handled, and whether a programming laptop gets its own port. SCADA is the plant screens and alarms above the machines. A retrofit should budget time to discover what is already there. Undocumented flat networks, everything on one switch, are common.
Practical next step If a customer security review is blocking a project, start with a controls and network audit. Orgenis maps the plant network as it actually is, and a step-by-step fix that operations can live with.
Discuss a controls platform decision or plant automation roadmap with Orgenis.