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.

Top Event

Restating the top event, this is the end action or consequence we are interested in analysing. In the case of our router installed at the UGH facility, the undesirable event which we want to avoid is the lack of a response from the router to our service level monitoring system. We'll simply refer to this as isolation of the router as a shorter way of noting this.

The undesireable event is "Router Isolation" and we start our fault tree diagram by placing this undesireable event in an event box at the top of our diagram.

The selection of what the undesireable event should be is the most important step. This should always be the first step. Figure out what event you want to assess or avoid and model downwards from this point what other factors could contribute to this. If you wind up working upwards from this point in your diagram, you really need to reassess exactly what the problem is. 




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