Quantitative Network Engineering with Fault Tree Analysis

This is a simple paper outlining how to use some Risk Analysis Techniques with Network Engineering to obtain quantitative results. An attempt to turn network engineering from an artful guessing game into a science.

Finding the Miniumum Cutsets

At this point our cutsets are as follows:

Cutsets
P V
P W
P H
P Y
P X
P S
P U
Q V
Q W
Q H
Q Y
Q X
Q S
Q U
H V
H W
H H
H Y
H X
H S
H U
T V
T W
T H
T Y
T X
T S
T U
R V
R W
R H
R Y
R V
R W
R U
S V
S W
S H
S Y
S X
S S
S U
O V
O W
O H
O Y
O X
O S
O U
K
L M
M N
N L
F G
F H
I G
I H
J
A
B D
B E
C D
C E

After applying the Idempotent rule of boolean algebra ( x OR x = x and x AND x = x ) and then sifting through the events to remove the combinations that are a redundant subset of a more basic sequence of events, the cutsets are trimmed down to the minimal ones. Drawing an analogy to IP networking, think of this as looking for the aggregate sequences and not advertising the more specifics.

Minimal Cutsets
P V
P W
P Y
P X
P U
Q V
Q W
Q Y
Q X
Q U
H
T V
T W
T Y
T X
T U
R V
R W
R Y
R V
R W
R U
S
O V
O W
O Y
O X
O U
K
L M
M N
N L
F G
I G
J
A
B D
B E
C D
C E

Link: The Fully Developed and Labeled Fault Tree in SVG format.



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