Maximum tolerable downtime (MTD)
- Term
- Maximum tolerable downtime (MTD)
- Exam
- CISA & CISM
- Definition
The longest a process can be unavailable before the damage becomes unacceptable.
- Explained
MTD is the outer limit of how long a process can be unavailable before the organization suffers unacceptable harm. The RTO must sit within it, usually with a margin.
- In practice
After 24 hours without payroll, the damage becomes unacceptable, so the RTO is set at 12 hours.
- Often confused with
- Recovery time objective
- Exam angle
The RTO sits within the MTD.
- Related
Recovery time objective (RTO) ยท Business impact analysis (BIA)