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CISSP_Candidate
08-29-2006, 04:54 PM
The nonprofit organization that you are an advisory board member of has decided to go forward with the proposed Internet and email connectivity project. The CEO would like to know how much money, if any, will be saved through the purchase of anti-virus software. Here are the project details:

20 computers connected to Internet
90% probability of virus infection
10 paid employees who make $12 an hour
A successful virus outage could bring down the network for an entire day
20 copies of antivirus will cost a nonprofit of $500

A. $960
B. $0
C. $1,290
D. $364

The Answer is D, but I dont understand how they get the SLE (AV x EF) of $960 in the first place??

Jescoi
08-29-2006, 04:54 PM
The AV = 10*12*8 = 960 (10 unproductive employees making $12/hr for 8 hours).

The exposure factor = 100% (Entire network down for the day), so:

SLE = 960*100% = $960

The ALE = $960 * 0.9 (90% probability of it happening) = $864

So you spend $500 to prevent a $864 loss -- net savings of $364.