Dr. R. Holz | People Pages: Find employees & contact details

I am a Full Professor at the University of Münster, and I also work part-time in the Design and Analysis of Communication Systems Group at the University of Twente.

Until 2019, I was a Lecturer in Networks and Security at the University of Sydney (that’s Asst. Prof. in other systems), Australia. Before that, I was a Researcher at NICTA (later CSIRO's Data61), also in Sydney, where I worked on network security and was part of the Security Business Team.

I hold a PhD from Technical University of Munich. I did both my post-grad and under-grad studies at Eberhard Karls University, Tuebingen, one of Germany’s classic universities.

Organisations

My research interests revolve around understanding and improving the Internet for everyone, with a particular focus on security aspects. Most recently, I have been working on

Global-scale measurement of Internet service deployments and their security
Data-driven security mechanisms
Analysis of emerging technology and its implications

I view my work through the lens of real-world implications. The tech is not always what matters—it’s the embedding in our world that makes it meaningful. Hence, I work with other disciplines and industry alike to make the Internet a safer, more secure, and altogether more interesting and useful place.

Publications

2025

Web Crawl Refusals: Insights From Common Crawl (2025)In Passive and Active Measurement: 26th International Conference, PAM 2025, Virtual Event, March 10–12, 2025, Proceedings (pp. 197–214) (Lecture Notes in Computer Science; Vol. 15567). Springer. Ansar, M., Sperotto, A. & Holz, R.https://doi.org/10.1007/978-3-031-85960-1_9

2024

Is a Name Enough? A First Look into Detecting Clouds Using DNS Pointer Records (2024)In 2024 20th International Conference on Network and Service Management (CNSM) (pp. 1-5). Article 10814277. IEEE Advancing Technology for Humanity. Tarahomi, S., Sommese, R., de Boer, P.-T., Linssen, J., Holz, R. & Sperotto, A.https://doi.org/10.23919/CNSM62983.2024.10814277Boosting Communication Efficiency of Federated Learning's Secure Aggregation (2024)In 2024 54th Annual IEEE/IFIP International Conference on Dependable Systems and Networks - Supplemental Volume, DSN-S 2024 (pp. 157-158). IEEE. Nazemi, N., Tavallaie, O., Chen, S., Zomaya, A. Y. & Holz, R.https://doi.org/10.1109/DSN-S60304.2024.00045Analysis of DNS Dependencies and their Security Implications in Australia: A Comparative Study of General and Indigenous Populations (2024)[Working paper › Preprint]. ArXiv.org. Nazemi, N., Tavallaie, O., Mandalari, A. M., Haddadi, H., Holz, R. & Zomaya, A. Y.https://doi.org/10.48550/arXiv.2408.12958Assessing the security of Internet paths: A case study of Dutch critical infrastructures (2024)In ANRW 2024 - Proceedings of the 2024 Applied Networking Research Workshop (pp. 67-73). Association for Computing Machinery. Khadka, S. K., Bayhan, S., Holz, R. & Hesselman, C. E. W.https://doi.org/10.1145/3673422.3674899PerFail 2024: Third International Workshop on Negative Results in Pervasive Computing - Welcome and Committees (2024)In 2024 IEEE International Conference on Pervasive Computing and Communications: Workshops and other Affiliated Events (PerCom Workshops) (pp. 38-39). IEEE. Peltonen, E., Mohan, N., Zdankin, P., Josten, M., Shreedar, T., Shreedhar, T., Bayhan, S., Berrocal, J., Chakraborty, S., Crowcroft, J., Ding, A. Y., Ferlin, S., Gasser, O., Holz, R. G., Kangasharju, J., Kolcun, R., Nicklas, D., Ott, J., Schiele, G., … Weis, T.https://doi.org/10.1109/PerComWorkshops59983.2024.10502953Towards Security Transparency of Autonomous Systems on the Internet (2024)In Computer Security. ESORICS 2023 International Workshops: CPS4CIP, ADIoT, SecAssure, WASP, TAURIN, PriST-AI, and SECAI, The Hague, The Netherlands, September 25–29, 2023, Revised Selected Papers, Part II (pp. 510-513) (Lecture Notes in Computer Science; Vol. 14399). Springer. Khadka, S. K., Holz, R. & Hesselman, C.https://doi.org/10.1007/978-3-031-54129-2_30LanDscAPe: Exploring LDAP Weaknesses and Data Leaks at Internet Scale (2024)In Proceedings of the 33rd USENIX Security Symposium (pp. 1225-1242). USENIX Association. Kaspereit, J., Öndarö, G., Cesar, G. L., Ebbers, S., Ising, F., Saatjohann, C., Jonker, M., Holz, R. & Schinzel, S.

2023

Packed to the Brim: Investigating the Impact of Highly Responsive Prefixes on Internet-wide Measurement Campaigns (2023)Proceedings of the ACM on Networking, 1(3). Article 24. Sattler, P., Zirngibl, J., Jonker, M., Gasser, O., Carle, G. & Holz, R.https://doi.org/10.1145/3629146Mobile apps and children's privacy: A traffic analysis of data sharing practices among children's mobile iOS apps (2023)Archives of disease in childhood, 108(11), 943-945. Pimienta, J., Brandt, J., Bethe, T., Holz, R., Continella, A., Jibb, L. & Grundy, Q.https://doi.org/10.1136/archdischild-2023-325960

Research profiles

I currently teach:

Empirical Security Analysis & Engineering (202100073)

I am a Fellow of the UK's Higher Education Academy.

Affiliated study programs

Courses academic year 2025/2026

Courses in the current academic year are added at the moment they are finalised in the Osiris system. Therefore it is possible that the list is not yet complete for the whole academic year.

Courses academic year 2024/2025

Courses academic year 2023/2024

Address

University of Twente

Zilverling (building no. 11)
Hallenweg 19
7522 NH Enschede
Netherlands

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