Software Fault Tree Analysis Tools

The Software Reliability Analysis module for Frestimate is used to generate software fault trees using the Isograph Reliability Workbench  product.  The following are the most common software failure modes and root causes. The tool generates a software fault tree using the below failure modes and root causes.  Each of the below leaves is aportioned part of the software failure rate prediction for the particular software LRU.  The relative frequency of each failure mode/root cause can be determined from actual problem reporting data or analytically by a software FMEA.


For each software LRU, a software fault tree has been created.  The top level failure rate for each software LRU is apportioned to each of the 28 failure modes based on your inputs to the Fault Tree Options tab in the Frestimate System Reliability Model tool.  These fault trees can be merged into the system level fault trees.

Example of a software fault tree analysis


Order ** single computer license for the Frestimate System Software Reliability Module

**Privacy Policy

We take your privacy seriously and will take all measures to protect your personal information.Any personal information received will only be used to fill your order. We will not sell or redistribute your information to anyone.

**Refund Policy

Refunds are provided at 100% of purchase price if and only if the product license has not been activated. However, once the license has been activated, no refunds are provided.

The Frestimate software is provided as a single computer license.  It can be installed on exactly one computer.

**Legal disclaimers copyrights and intellectual property