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.

Events

Everything in Fault Tree Analysis is an event or a gate (and depending on which literature you read a gate is also a type of event). There are several types of events.

Top Event
This is the end action we are interested in analysing. It is the very top of the analysis and the point from which everything will branch off. All of the logic in the diagram will flow upwards to this point and contributes to the probability of occurrence of the top event. The top event is represented by a box symbol at the top of the diagram.
Intermediate Event
This is an event which has other contributing factors into leading to it's occurrence. An intermediate event is represented by a box symbol.
Basic Event
This is an initiating event or failure, and the lowest level of our model. A probability can be assigned to a basic event. Event though a basic event could be broken down into more detail with more contributors, this is the furthest detail that the model will be developed to. The basic event is also referred to as a leaf node, as it is a terminating point on the tree. A basic event is represented by a box with a circle subscript or just a circle.

Event Symbols

Event


Basic Event




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