Every industry with a control network has a line to hold.
Wherever a business network meets the systems that run a process, a few firewall rules decide what can cross. Pick an industry to see where that line usually sits, one crossing that should not be there, and the rules it answers to.
- ManufacturingStop one bad laptop from stopping the line.
- Water and wastewaterKeep the treatment plant off the office network.
- Oil and gasKeep the pipeline running when IT has a bad day.
- Electric powerSee every firewall rule into the Electronic Security Perimeter.
- Pharmaceuticals and life sciencesProtect the batch, not just the network.
- Defense manufacturingShow the shop floor is scoped, not forgotten.
- Ports and maritimeGet terminal segmentation ready before the Coast Guard asks.
- Rail and transitKeep passenger systems away from signaling.
- Warehousing and logisticsKeep the dock moving when the office network goes down.
Manufacturing
Discrete and process manufacturers connect ERP, MES and the line to move faster, and every connection is a firewall rule someone has to keep right. SegAudit shows which rules let the business network reach the line, which ones the traffic log never shows in use, and the change for each.
What crosses the line in manufacturing
Each one is a finding ranked by risk, with the rule that allows it, the hosts that used it when a traffic log is loaded, and the change that closes it.
- Office laptops on the line
A rule written for one integrator lets the whole office subnet reach robot cell controllers.
- ERP talking straight to PLCs
Production orders reach the PLCs straight from ERP instead of passing down through MES and the line's own supervisory systems.
- One flat network
Every line shares one zone, so a problem on one line can reach the next.
- Rules the traffic log never shows in use
Rules into the site that no session used in the traffic log, ready to retire once the log covers maintenance and batch runs.
Illustrative examples of what an audit can find. They are not from a customer.
The rules manufacturing answers to
SegAudit judges the controls a firewall's evidence can speak to as supported, partial or gap, and shows each one again after the change. It helps you assess segmentation; it does not certify compliance.
| Rule | What it asks of segmentation | Judged from the evidence |
|---|---|---|
| IEC 62443-3-3 | Zones and conduits: network segmentation (SR 5.1), zone boundary protection (SR 5.2) and least functionality. | 9 controls |
| NIST CSF 2.0 | Networks protected from unauthorized logical access (PR.IR-01), asset inventories and log monitoring. | 10 controls |
| ISO/IEC 27001:2022 Annex A | Segregation of networks (A.8.22), networks security (A.8.20) and logging. | 7 controls |
| NIS2 Article 21(2) | Cybersecurity risk-management measures for essential and important entities in the EU. | 6 controls |
Control by control in the frameworks overview. Confirm the versions in force for your audit period.
Who runs the audit
The same audit either way. What differs is who approves the change.
Asset owners
Your own firewall team runs the audit on its own sites, every quarter, and approves each change through its own change process. Priced per site with the Asset Owner edition.
For asset ownersConsultants
You assess a client's sites and deliver the findings and the fix under your firm's letterhead. The client's team approves. Professional or Engagement.
For consultantsSee what crosses the line on your own firewalls.
Export a firewall configuration, add a traffic log if you have one, and read the findings on your own workstation. Nothing leaves it, and SegAudit never connects to your network.
Step-by-step export guides, for customers and trial holders: Palo Alto, FortiGate, Cisco ASA, Cisco FTD, Check Point.