ISC2 Certified in Cybersecurity (CC)Security PrinciplesMedium
A company's email server experiences a major outage, rendering all email services unavailable for 8 hours. The company estimates this outage cost them $5,000 per hour in lost productivity and business. They are considering implementing a redundant email system that costs $30,000. What is the single loss expectancy (SLE) for this email server outage?
- A$65,000
- B$30,000
- C$40,000
- D$5,000
Show answer & explanationAnswer & explanation
Correct answer: C. $40,000
The Single Loss Expectancy (SLE) is the cost of a single occurrence of a risk event. In this case, 8 hours of outage at $5,000/hour equals $40,000.
Why the other options are wrong
- A. $65,000 is an incorrect calculation, possibly combining the SLE and the solution cost.
- B. $30,000 is the cost of the proposed solution (redundant system), not the loss from the outage.
- D. $5,000 is the cost per hour, not the total loss.
Single Loss Expectancy (SLE)
The monetary loss expected from a single occurrence of a specific risk event.
- Calculated as Asset Value (AV) multiplied by Exposure Factor (EF).
- AV represents the value of the asset at risk.
- EF represents the percentage of asset value lost due to a single incident.
Memory trick: Quantify risk with SLE, ARO, and ALE: Sleeping makes you lose money, Annual Recurrence makes it happen, and Annual Loss is the total damage.