Industrial Control System Cybersecurity Lifecycle
The stages that a physical process or a management system goes through as it proceeds from start to end. These stages include conception, design, deployment, acquisition, operation, maintenance, decommissioning, and disposal.
Assess Phase
The first phase of the cybersecurity lifecycle is the assessment or analysis phase. In this phase, the IACS (Industrial automation & control system) is identified, segmented into zones, and analyzed for risk. The requirements for the design are then defined. The objective of the assessment phase is to identify any shortcomings in the current cybersecurity of the facility.
Key Activities
- Identify the IACS components
- Segment into security zones
- Perform risk analysis
- Define security requirements
Implement
The objectives for the implementation phase are to have a complete design that meets the requirements of the cybersecurity requirements and to have those designed countermeasures and systems implemented in the physical equipment. The implementation phase of the cybersecurity lifecycle includes the application of countermeasures, security level verification, and testing activities that make up the bulk of an upgrade, retrofit, or new project.
Key Activities
- Design security countermeasures
- Implement physical security measures
- Verify security level requirements
- Conduct testing and validation
Maintain
The cybersecurity lifecycle defines the maintenance phase as beginning with the actual operation of the plant or equipment. Therefore, the first step in the maintenance phase is a startup, followed by maintenance activities, ongoing security monitoring, periodic audits, and modification/decommissioning. The objective of the maintenance phase is to ensure that the level of cybersecurity for the IACS can be managed consistently throughout the lifecycle of the facility.
Key Activities
- Startup and commissioning
- Regular maintenance activities
- Ongoing security monitoring
- Periodic security audits
- Modification and decommissioning
The hardware assets of the IACS require periodic maintenance to maintain their cleanliness and correct operations.
Conclusion
If cybersecurity is not addressed in each of these phases, the safety and integrity of the IACS may not be achieved. A comprehensive approach covering assessment, implementation, and maintenance is essential for robust ICS cybersecurity.