During disasters, crisis, and emergencies the public relies on online services provided by official authorities to receive timely alerts, trustworthy information, and access to relief programs. It is therefore crucial for the authorities to reduce risks when accessing their online services. This includes catering to secure identification of service, secure resolution of name to network service, and content security and privacy as a minimum base for trustworthy communication.

Select an Alerting Authority…



* You can also download the raw data and our toolchain on zenodo.

You can download the full study here.

If you cite this study, use data or tools, please, refer as follows:

Pouyan Fotouhi Tehrani, Eric Osterweil, Jochen H. Schiller, Thomas C. Schmidt, Matthias Wählisch, Security of Alerting Authorities in the WWW: Measuring Namespaces DNSSEC and Web PKI, In: Proceedings of The Web Conference 2021 (WWW '21), New York, USA: ACM, 2021.


This project is the result of an interdisciplinary cooperation of Weizenbaum-Institut for the Networked Society, Fraunhofer FOKUS, Freie Universität Berlin, Hamburg University of Applied Sciences, and George Mason University.

In case of questions, please, contact Pouyan Fotouhi Tehrani.

  • Pouyan Fotouhi Tehrani PhD-Candidate at The Weizenbaum Institute for the Networked Society.

  • Eric Osterweil Assistant Professor, Department of Computer Science at George Mason University.

  • Jochen Schiller Professor, Instiute of Computer Science at Freie Universität Berlin.

  • Thomas C. Schmidt Professor, Department of Informatik at Hamburg University of Applied Sciences.

  • Matthias Wählisch Professor, Institute of Computer Science at Freie Universität Berlin.