## Assessing network availability: theory and practice

**Robert Kooij**Senior Scientist at TNO

Professor at TU Delft

An important measure for the quality of a network is its availability. The availability of a network is defined as the probability, given the availability of individual network elements, that the network is connected. In this presentation we first discuss a remarkable theoretical result about the so-called reliability polynomial, which is a representation of the network availability in terms of the individual link availabilities. In the second part we discuss a real-life use case, the Texel gas distribution network.

## About Robert Kooij

Robert Kooij has a background in mathematics: he received his PhD degree cum laude at Delft University of Technology, in 1993. From 1997 until 2003 he was employed at KPN Research. Since 2003 he is employed at TNO, where he deals with quality aspects of ICT networks. In 2011 he became Principal Scientist, conducting and managing research on Critical ICT Infrastructures.

Since 2005 Robert is part-time affiliated with the Delft University of Technology, at the faculty of Electrical Engineering, Mathematics and Computer Science. Since 2010 he is a part-time full professor with the chair ""Robustness of Complex Networks".

His research currently focusses on both theoretical assessment of robustness and availability of networks, and on the application of these concepts to critical infrastructures, such as power grids, water distribution networks and gas distribution networks.