Security Governance · Topic 2 of 3
Business Continuity and Disaster Recovery
Redundancy for the CC exam: business continuity and disaster recovery plans, the BIA, RTO and RPO, backups, failover, load balancing, sites and AI model drift.
- 3 min
- BC keeps the business running; DR restores IT.
- The BIA comes first and sets RTO and RPO.
- RTO is time to recover; RPO is acceptable data loss.
What it is
Redundancy keeps an organization working when something fails. Business continuity (BC) keeps critical business functions running during a disruption. Disaster recovery (DR) restores IT systems and data after a disruption. Both depend on duplicates: of data, systems, sites and suppliers.
How it works
BC and DR
| Business continuity | Disaster recovery | |
|---|---|---|
| Focus | Keeping the business running | Restoring IT systems and data |
| Scope | People, processes, suppliers, facilities, IT | Mainly technology |
| Example | Staff work from another office | Servers restored at a recovery site |
Both start with a business impact analysis (BIA), which finds the critical functions and how long the business can survive without them.
Recovery targets
| Term | Meaning |
|---|---|
| RTO (recovery time objective) | How quickly a system must be back |
| RPO (recovery point objective) | How much recent data may be lost |
Redundancy techniques
| Technique | What it does |
|---|---|
| Backups | Copies of data to restore after loss |
| Failover | A standby system takes over when the primary fails |
| Load balancing | Spreads requests across several servers so none is overloaded |
| Replication | Keeps copies of data on more than one system |
| Redundant power | UPS and generators |
| Alternate sites | Hot (ready to go), warm (partly ready) or cold (space and power only) |
| Second supplier | Removes dependence on one provider |
Backups protect data but may take hours to restore. To keep a service running through a site outage, you need a standby at a second site with failover.
Redundancy for AI systems
- Back up the model files and training data, not just reports or servers, so you can restore the model's behaviour.
- Plan for model drift: a model's accuracy can fall as real-world behaviour changes. The fix is to monitor accuracy and retrain, not failover or backups.
- Avoid depending on a single external AI provider with no fallback.
Testing plans
Plans must be tested: walkthroughs and tabletop exercises, simulations, parallel tests and, rarely, full interruption tests. Untested plans often fail when needed.
How the exam asks about this
- "Which approach spreads requests across several servers?" Load balancing.
- "A fraud model grows less accurate over the year." Monitor accuracy and retrain.
- "Which plan keeps business functions running during a disruption?" The business continuity plan.
What to remember for the exam
- BC keeps the business running; DR restores IT.
- The BIA comes first and sets RTO and RPO.
- RTO is time to recover; RPO is acceptable data loss.
- Backups, failover, load balancing, replication and alternate sites provide redundancy.
- For AI, back up models and training data, and watch for model drift.
A bigger server at the same site does not help when the whole site is down. Redundancy must avoid shared points of failure.
Common mistakes
Confusing BC with DR.
Mixing up RTO and RPO.
Treating backups as instant availability.
Check yourself
What does RPO measure?
How much recent data the business can afford to lose.
Which plan restores IT systems after a disaster?
The disaster recovery plan.
What should be backed up to restore an AI tool's behaviour?
The model files and the training data.
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