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.

Initial System

Here is how the Megabox 2000 Turbo++ is installed at the Unreliable Hosting Group or UHG for short.

This Megabox 2000 Turbo++ was spec'd out as a mix of cheap and redundant. It has dual Routing Control Engines (RCEs), the bare minimum number of Switch Fabrics (SFs)...two, a single Forwarding Engine (FE) that hosts two Line Cards (LCs) each with it's own connection to a different ISP. The router has two power supplies, each plugged into a single uninterruptible power supply (UPS) which was purchased from Blackhole Networks sister company Brownout PowerSystems. Power is provided directly from the local commerical provider.

You may be wondering what this router is used for, as it doesn't seem to have any customer or user circuits installed on it. This is one of hundreds of routers installed by UHG that acts as a target for pings from the service level monitoring system. The service level system is setup to monitor a loopback address on the router. These stats will feed into the network availablity numbers for UHG. Even though this router isn't really doing anything, it is of the utmost importance that it remain active so the providers numbers look better than they actually are.

The Blackhole Networks Megabox 2000 Turbo++ Router installed at the Unreliable Hosting Group's datacenter in Jaqueass, Quebec, Canada




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      |   Version 0   |       C       |            Plenty             |
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      |           Router ID - www.blackhole-networks.com              |
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      |           Area ID - FTA with Network Engineering              |
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      |          Checksum  OK         |         Construction          |
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      |                       CONSTRUCTION                            |
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