Define the operating boundary
A useful definition names the triggering event, required inputs, governing source, accountable owner, decision or action, exception path, evidence retained, and downstream handoff. Buyers should adapt those elements to their own population, jurisdictions, policies, systems, and control model before writing requirements.
The most important distinction is between a label and an operational capability. A provider may document industrial firewall and policy enforcement while depending on customer-supplied policy, licensed content, third-party data, integration partners, manual review, or services. The demonstration should expose those dependencies rather than hiding them behind a completed interface.
What a demonstration should prove
- Begin with representative source records and a named policy, standard, or controlled rule.
- Show the normal path, an ambiguous case, missing data, an exception, an override, and a material source change.
- Identify who can change rules, who can approve or reject, and how accountability is preserved.
- Trace every output back to inputs, versions, timestamps, user actions, and governing evidence.
- Export the resulting record and reconcile it with downstream systems and retained obligations.
Authority and operating context
IEC PAS 62443-2-2:2025
The specification provides guidance for developing, validating, operating, and maintaining a set of technical, physical, and process security measures for IACS facilities. It focuses the buyer on a maintained protection scheme rather than an isolated product or control purchase.
ISA/IEC 62443-3-2
Part 3-2 addresses system-level risk assessment and the use of zones, conduits, and target security levels in IACS design. It provides the central architecture language for comparing discovery, segmentation modeling, enforcement, remote access, and controlled-transfer products.
ISA/IEC 62443-3-3
Part 3-3 defines system security requirements and security levels for industrial automation and control systems. It helps structure system-level requirements, but capability marketing and certification labels need exact scope, version, and scheme evidence.
CISA primary OT mitigations
The fact sheet calls attention to exposed OT connectivity and prioritizes defensive actions for owners and operators facing intentional targeting. It makes internet exposure, remote access, credentials, segmentation, inventory, logging, and recovery evidence central to product and architecture review.
Operating domains
Network architecture, segmentation, and conduits
The design and maintained evidence for security zones, conduits, trust boundaries, routable paths, industrial DMZs, enforcement points, fail states, and allowed communication supporting physical operations.
Safety, reliability, and engineering coordination
The decision boundary connecting cyber defense with process safety, functional safety, reliability, operations, maintenance, engineering change, and physical consequence.
Evidence and comparison limits
Official provider documentation can establish product positioning. Provider confirmation can clarify package or availability. Independent observation requires a disclosed scenario, environment, date, inputs, and reproducible result. None of those sources alone establishes buyer-specific legal, clinical, regulatory, quality, or operational fitness.
Buyer questions
- What exact outcome and evidence should industrial firewall and policy enforcement produce?
- Which source, version, and customer facts govern the workflow?
- Which decisions remain human and who is accountable for them?
- What is native, configured, integrated, service-delivered, or planned?
- How does a changed source affect open and historical records?
Recent changes
CISA partners publish primary mitigations for OT — Owners should review exposure, access, architecture, credentials, monitoring, and recovery through site-authorized engineering processes.
IEC publishes PAS 62443-2-2:2025 — Asset owners should evaluate technology as part of a maintained technical, physical, and process protection scheme.