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.

Analysis of the Miniumal Cutsets

Reviewing our minimal cutsets there are a total of 39 different combinations of events that will cause our entire system to fail. Of these, there are five first order cutsets where a single failure will cause the top event to occure. These are single points of failure in our system. There are 34 second order cutsets whereby two separate failures are needed in order to cause the to event.

. 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

Despite the efforts of the system designers there are five separate and distinct single points of failure: H, S, K, J and A.




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