While the overall risk analysis should be conducted
by the AIS technical manager, other personnel at the
AIS facility can contribute to the threat analysis, and
their help should be requested. Table 4-2 includes a list
of common threats at a shore AIS facility, with space
for listing the agency or individual to contact should the
need arise. Your AIS facility should have a similar list
with local contacts of help and information.
Annual Loss Expectancy
The third step in the risk analysis is to combine the
estimates of the value of potential loss and probability
of loss to develop an estimate of annual loss expectancy.
The purpose is to pinpoint the significant threats as a
guide to the selection of security measures and to
develop a yardstick for determining the amount of
money that is reasonable to spend on each of them. In
other words, the cost of a given security measure should
relate to the loss(es) against which it provides
protection.
To develop the annual loss expectancy, construct a
matrix of threats and potential losses. At each
intersection, ask if the given threat could cause the given
loss. For example, fire, flood, and sabotage do not
cause theft-of-information losses; but, in varying
degrees, all three result in physical destruction losses
and losses because of delayed processing. Likewise,
internal tampering could cause an indirect loss of assets.
In each case where there can be significant loss, the loss
potential is multiplied by the probability of occurrence
of the threat to generate an annual estimate of loss.
Remedial Measures Selection
When the estimate of annual loss is complete, AIS
upper management will have a clear picture of the
significant threats and critical AIS tasks. The response
to significant threats can take one or more of the
following forms:
Alter the environment to reduce the
probability of occurrence. In an extreme case,
this could lead to relocation of the AIS facility
to a less-exposed location. Alternatively, a
hazardous occupancy adjacent to or inside the
AIS facility could be moved elsewhere.
Erect barriers to ward off the threat. These
might take the form of changes to strengthen the
building against the effects of natural disasters,
Table 4-2.—Threat Help List
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