# About

> Markdown version of https://dtrautwein.eu/about/

I measure the performance of systems where no central telemetry collection is possible, and then try to make them faster.

[ProbeLab](https://probelab.io) began in 2022 as a team at [Protocol Labs](https://protocol.ai). In 2025,
[Yiannis Psaras](https://github.com/yiannisbot), [Mikel Cortes-Goicoechea](https://github.com/cortze)
and I founded it as its own company. We watch how global peer-to-peer networks behave in practice: how
peers find each other, how long lookups take, which nodes stay online and which vanish after an hour.
Then we publish it, and argue for and implement the protocol changes that the measurements imply.

In 2026 I finished a PhD in computer science at the University of Göttingen, in
[Bela Gipp's group](https://gipp.com). The
[thesis](https://ediss.uni-goettingen.de/handle/11858/16480) is about measuring and optimising
peer-to-peer networks, with IPFS as the case study.

Some results, each one done with the ProbeLab team or my co-authors:

- [Optimistic Provide](https://blog.ipfs.tech/2026-05-optimistic-provide/) made publishing content
  to the IPFS DHT ten times faster and cut its network overhead by 40%. It started in my PhD, became
  an INFOCOM paper, and has been on by default since Kubo 0.39.0.
- My [study of the Hydra booster nodes](https://github.com/probe-lab/network-measurements/blob/master/results/rfm21-hydras-performance-contribution.md)
  found that they added about 10% to DHT performance. Based on that, Protocol Labs
  [switched them off](https://discuss.ipfs.tech/t/dht-hydra-peers-dialling-down-non-bridging-functionality-on-2022-12-01/15567)
  in 2023.
- The [NAT traversal study](https://arxiv.org/abs/2604.12484) for IMC 2026 looked at 4.4 million
  hole punching attempts from 167 countries. About 70% succeed, over TCP as often as over QUIC, which
  contradicts the common view that UDP works better.
- [Nebula](https://github.com/dennis-tra/nebula), my protocol agnostic peer-to-peer network crawler. It feeds the graphs on probelab.io and the
  [network metrics](https://metrics.gnosischain.com/) of Gnosis.

Before that: physics at [Christian-Albrechts-University in Kiel](https://www.uni-kiel.de/de/), where
our student team flew a particle detector into the stratosphere on the
[BEXUS 19](https://adam.physik.uni-kiel.de/) balloon. Then backend work at
[freiheit.com](https://freiheit.com/en/) in Hamburg on the real time event backend behind Daimler's
Mercedes me app, then [OriginStamp](https://originstamp.com/) in Switzerland, then
[Protocol Labs](https://protocol.ai).

I write most of my code in Go, and the analysis in Python. I built much of ProbeLab's measurement
infrastructure and run it today. I still build small things for fun, and some of them are on the
[side projects](/projects/) page.

If you want to talk about network measurement, or you have data you think I would enjoy, send
me an email.

## Experience

- **Co-founder**, [ProbeLab](https://probelab.io) (2025 to now, Kiel, Germany). Founded with Yiannis Psaras and Mikel Cortes-Goicoechea. We measure various peer-to-peer networks, publish what we find, and feed it back into protocol design.
- **Research engineer**, [Protocol Labs / IPShipyard](https://protocol.ai/) (Sep 2022 to 2025, Remote). Measurement of the IPFS and libp2p networks: crawlers, telemetry, and the analysis that turns raw data into something a protocol team can act on. The ProbeLab team started here.
- **Doctoral researcher**, [University of Göttingen](https://gipp.com) (2020 to 2026, Göttingen, Germany). PhD in computer science in Bela Gipp's group. The thesis measures and optimises peer-to-peer networks, with IPFS as the case study.
- **Industrial PhD candidate**, [OriginStamp AG](https://originstamp.com/) (May 2020 to 2022, Kreuzlingen, Switzerland). Frontend work in Angular, alongside the infrastructure work that kept the company running on AWS and Terraform.
- **Software engineer**, [freiheit.com](https://freiheit.com/) (Jul 2018 to Apr 2020, Hamburg, Germany). Built the real time event backend behind Daimler's Mercedes me app, in a Go and Kubernetes setup on Azure.
- **Web and mobile developer**, [weluse GmbH](https://weluse.de) (Jan 2017 to Jun 2018, Kiel, Germany). Led a web application for property managers and worked on client sites mostly in React.
- **Research assistant**, [CAU Kiel](https://www.uni-kiel.de/) (2017, Kiel, Germany). Frequency analysis of image sets from a photoemission electron microscope, plus a Java tool that drove the microscope and its peripherals.
- **Software developer**, [TouchTech Labs](https://touchtechlabs.com) (Mar to Sep 2016, Melbourne, Australia). Interactive web applications for a mixed set of clients, and the client meetings that came with them.
- **iOS developer intern**, [TouchTech](https://www.touchtech.co.nz) (Jul 2015 to Mar 2016, Wellington, New Zealand). Shipped two iOS apps on my own, one promotional and one for tracking employee performance.

## Education

- **PhD, Computer Science**, University of Göttingen, 2026. Thesis: [Measuring and Optimizing Peer-to-Peer Networks: A Case Study of the InterPlanetary File System](https://ediss.uni-goettingen.de/handle/11858/16480).
- **MSc, Physics**, Kiel University, 2018. Thesis: [Plasmonic excitations in TMDC-gold hybrid systems](https://dtrautwein.eu/files/MA-Dennis-Trautwein.pdf) (in German).
- **BSc, Physics**, Kiel University, 2014. Thesis: [GEANT4 simulations of the ADAM sensor system for BEXUS 19](https://dtrautwein.eu/files/BA-Dennis-Trautwein.pdf) (in German).

## Service

- **Reviewer, JCDL** (ACM/IEEE Joint Conference on Digital Libraries).