Fault Tree Analysis for Safety Critical Network Infrastructure

A hybrid framework to perform reliability analysis for Safety Critical Network Infrastructure (SCNI) is developed. A Campus Wide Area Network (CWAN) that provides web and other services connectivity to several departments forms a model of SCNI backbone for this study. In order to deliver a high performance network with efficient management, trouble shooting environment, and scalable topology, a multi-tier approach has been adopted. This SCNI model has three layers viz., core layer, distribution layer, and access layer. For the purpose of carrying out reliability analysis, the hardware components and software functions are represented by Reliability Block Diagrams (RBD). The input to each RBD forms the test criteria while, corresponding output from each RBD represents the response of each hardware component or, software function to the test criteria. The FTA goes further down by trying to identify the ischolar_main cause of each component's failure.