Glossary · Industrial cybersecurity
Security zone
Also known as: zone
German: Sicherheitszone
In industrial cybersecurity under IEC 62443, a security zone is a grouping of logical or physical assets with common cybersecurity requirements and risk characteristics. Each zone has a target security level, and communication between zones runs through conduits.
- Cybersecurity
- Standards
In one sentence
A security zone in IEC 62443 groups assets with common cybersecurity requirements and risk, protected at a shared target security level.
Example
In a pressing plant, the safety PLCs and drives of each press line form one zone, the plant MES another, and the engineering workstations a third, each with its own target security level.
How it applies
- Cybersecurity: Zones are defined in the security risk assessment. Assets are grouped by criticality, function and location; a compromise in one zone should not spread freely to others. Connections run through conduits.
- Integrated systems: When a machine builder delivers a machine with its own network, it forms a natural zone. The integrator places it in the plant's zone model and defines what may cross its system boundary.
- Machine safety: Safety-related components often belong in a zone with a high target security level, since manipulation could affect safety functions.
- Technical documentation: Document zones with their assets, target security level, owner and conduits. This documentation must be updated when assets are added.
Security zone vs. safety zone
A security zone is a cybersecurity concept for network and asset grouping. A safety zone, as in safety zoning, is a physical area of a machine with its own protective measures. The terms sound alike but belong to different disciplines and should not be mixed in documentation.