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protection again, because these points have been added before in the Ax
calculation. This happens because addition occurs first based on columns, but
capping is done per row. The capping ensures that the effect per criterion does
not exceed the maximum credit allowed by Table 6-35.
c: The total amount of points capped that has to be subtracted from the overall
effectiveness of protection:
o: Additional points due to attack attempt considerations based on a specified
max(a, b): The largest of the given numbers a and b (maximum function).
min(a, b): The smallest of the given numbers a and b (minimum function).
The columns of Table 6-36 above show the evaluation criteria from section 3.6.2 as
evaluation steps (as described in section E.1.3) whereas the table rows represent the
three criteria described in sections E.1.3.1, E.1.3.2 and E.1.3.3. The last row is the
effectiveness of protection assessment.
Per cell, for example (“Protection” - “Technical” , Execution Means), the applicable
individual or combined (see section E.1.4) of security measures are listed together with
their corresponding points (see section E.1.3).
In order to calculate A x , the security measureś points of the column are added up
(column sum Ex) and added to the A x-1 value (the column on the left). If the column X
is already the leftmost column on the table (X=1), the column sum E 1 is added to the
initial effectiveness of protection (i.e. 1).
Therefore the effectiveness cells, A x , show the robustness level when the security
measures up to step X are taken into account.
As already mentioned in E.1.4 there are maximum combined effects for each of the
three criteria (execution means, windows of opportunity and preparation means),
represented by the rows in the calculation Table 6-36 .
These maximum effects are represented by the rightmost column in the evaluation table
called “Effectiveness Capping”. This column shows the amount of points to be
subtracted from the effectiveness of protection (A) because the points exceeding the
maximum were already added to the column sum Ex in the evaluation of the
If the effectiveness points value per row (E y , with y=p/w/e) is higher than the
maximum allowed for the corresponding criteria (max_effect y), the difference (i.e.
effectiveness capping, c y) is subtracted from the effectiveness of protection (A)
If not, the effectiveness capping is 0
This is what the following formula shows where y represents each row:
cy = max(Ey - max_effecty, 0)
The abovementioned procedure is performed per row (i.e. criteria) in the evaluation
Table 6-36. The total amount of points capped that has to be subtracted from the overall
effectiveness of protection is:
Even after applying the effectiveness capping, the effectiveness value may exceed 30
points. As shown in section E.1.4, there is a finite limit to the expertise and preparation
time of an attacker that renders higher effectiveness values meaningless. Therefore the
maximum effectiveness value is limited to the end of the scale at 30 points.
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