Probabilistic Risk Assessment In Communications Systems: A Case Study

Can a quick study using probabilistic risk assessment techniques provide valuable insight into the reliability of telecommunications service networks? In 2000, CoreExpress, now Williams Communications, chartered Sandia National Laboratories to evaluate the performance of an IP transport service offering. The paper describes the overall approach taken, some surprising findings, and, in hindsight, an assessment of the utility and limits of such analyses. We found that engineering features whose reliability might be taken for granted in traditional telecommunications applications (e.g., long-term backup power supplies, building heating and cooling systems, and double fiber cuts) can have significant effects on the availability of ultra-high reliability communication services.