Lose a laptop, lose how much?
A firm loses three laptops a year. Each one costs 800 pounds to replace. How much is that over a year? You can work it out in one line.
Then you write every risk in one list, so nothing is forgotten.
By the end of this lesson
Note
I can work out a yearly loss and record a risk in a register with a colour and an owner.
Key words
| Word | What it means | Example |
|---|---|---|
| ALE | annualised loss expectancy: the money a risk is expected to cost in one year | |
| SLE | single loss expectancy: the cost of one event | 800 pounds for one laptop |
| ARO | annual rate of occurrence: how many times it happens in a year | 3 laptops a year |
| Risk register | a table that lists every risk, its rating, its owner and its action | |
| Owner | the one person who makes sure the action is done | |
| RAG rating | a red, amber or green mark for how serious a risk is |
The cells students fill in are left blank in this preview.
Starter
Have a go
Starter
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
ALE: one year of loss
ALE is a number for one risk. Take the cost of one event (SLE). Multiply it by how many times it happens in a year (ARO).
So ALE is SLE times ARO. A big ALE means the risk is worth spending money on.
Worked example: two risks and their ALE
| Risk | SLE (one event) | ARO (per year) | ALE |
|---|---|---|---|
| Lost laptop | 800 pounds | 3 | 2400 pounds |
| Server room flood | 5000 pounds | 1 | 5000 pounds |
| Total for the year | 7400 pounds |
The cells students fill in are left blank in this preview.
Try it: work out an ALE
single_loss = 800
times_a_year = 3
ale = single_loss * times_a_year
print("ALE is", ale, "pounds")
# Change times_a_year to 5 and run it again.
The risk register
A risk register is a table. Each row is one risk. It holds the rating, the owner and the action.
Teams look at the register every month. Red rows get attention first. The register is the memory of the risk process.
One small risk register
| No. | Risk | RAG | Owner | Action |
|---|---|---|---|---|
| 1 | Only one backup copy, kept in the same room | Red | IT manager | Add an off-site copy this month |
| 2 | Security software is not updated | Amber | Support lead | Update at the next change window |
| 3 | Spare cables not labelled | Green | Support technician | Label them in the next quiet week |
The cells students fill in are left blank in this preview.