Isolated Backup

Isolated backup is a cybersecurity strategy in which Operational Technology (OT) data is stored in an environment that is physically or logically separate from the main network. This separation minimizes the risk of ransomware or other cyber threats compromising backup data, ensuring that critical information can be recovered during an incident.

Purpose of Isolated Backup

• Protection Against Ransomware: Prevents ransomware from encrypting or deleting backup data by isolating it from infected systems.
• Disaster Recovery: Ensures a clean copy of data is available for restoring operations after a cybersecurity incident.
• Compliance: Aligns with regulatory requirements and industry standards for secure data storage and recovery planning.

Key Features of Isolated Backup

1. Physical Separation: Backups are stored on disconnected media, such as external drives or offline storage, ensuring no network access.
2. Logical Separation: Data is stored in a separate network or cloud environment with strict access controls and firewalls.
3. Immutable Storage: Ensures backup data cannot be altered or deleted once written, protecting it from tampering.
4. Regular Testing: Verifies backup data is intact, accessible, and functional for recovery.

Benefits of Isolated Backup in OT

• Data Integrity: Ensures backup data remains unaffected by ransomware or other malicious activities.
• Operational Continuity: Reduces downtime by enabling rapid recovery of critical OT systems and data.
• Enhanced Security: Provides an additional layer of defense by segregating backups from production systems.
• Compliance Assurance: Helps meet regulatory standards for data protection and disaster recovery in critical infrastructure.

Challenges of Implementing Isolated Backup

• Cost: Physical and cloud-based isolated backups can require significant investment in infrastructure and resources.
• Management Complexity: Maintaining isolated backups involves additional operational overhead, including regular updates and monitoring.
• Access Restrictions: Strict access controls may complicate recovery processes if not well-documented and tested.
• Data Synchronization: Ensuring backups are up-to-date without exposing them to production systems requires careful planning.

Best Practices for Isolated Backup

1. Adopt the 3-2-1 Rule: Maintain at least three copies of data, store them on two different media types, and keep one copy offsite or isolated.
2. Use Immutable Storage: Ensure backup data cannot be altered or deleted to protect against insider threats and malware.
3. Implement Access Controls: Restrict access to backup environments, allowing only authorized personnel or systems.
4. Automate Backup Processes: Use automated solutions to reduce errors and ensure backups occur regularly.
5. Test Recovery Procedures: Conduct regular drills to confirm that backups can be restored effectively and quickly.

Examples of Isolated Backup in OT

• Offline Backup: Using external drives or tape storage that are physically disconnected after backups are completed.
• Air-Gapped Systems: Storing backups on systems not connected to any network ensures complete isolation.
• Cloud-Based Isolation: Using a secure cloud environment with separate credentials and access policies for storing OT backups.
• WORM (Write Once, Read Many) Storage: Leveraging immutable storage technology to ensure data cannot be altered or deleted.

Conclusion

Isolated backup is critical to OT cybersecurity, providing a robust defense against ransomware and other threats. By physically or logically separating backup data from production systems, organizations can ensure data integrity and rapid recovery in the event of an incident. While implementation may require additional resources and planning, enhanced security, operational continuity, and regulatory compliance make isolated backups a cornerstone of resilient OT environments.