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Leonard Bradatsch

Leonard Bradatsch holds a Bachelor degree in Media Informatics and a Master degree in Computer Science from Ulm University. He is currently employed as a research assistant at the Institute of Distributed Systems.

Research:

As part of my thesis, I am currently working on anomaly detection based on network traffic records.

Research Interests 

  • Low-level Programming in C and C++
  • All kinds of network infrastructures and protocols
  • Network Device and Protocol Testing
  • Network Behavior Analysis

Projects

  • bwNetFlow (started 2017/12 – 2020/06; not completed): Development of a toolchain for live data analysis and anomaly detection based on NetFlow records provided by the BelWü core routers.

Dataset Overview

Here you can find an overview of datasets that can be used for anomaly detection in computer networks.

Publications

2022

Bradatsch, L., Haeberle, M., Steinert, B., Kargl, F. and Menth, M. 2022. Secure Service Function Chaining in the Context of Zero Trust Security. 2022 IEEE 47th Conference on Local Computer Networks (LCN) (2022), 123–131. (acceptance rate: 24%)
Service Function Chaining (SFC) enables dynamic steering of traffic through a set of service functions based on classification of packets, allowing network operators fine-grained and flexible control of packet flows. New paradigms like Zero Trust (ZT) pose additional requirements to the security of network architectures. This includes client authentication, confidentiality, and integrity throughout the whole network, while also being able to perform operations on the unencrypted payload of packets. However, these requirements are only partially addressed in existing SFC literature. Therefore, we first present a comprehensive analysis of the security requirements for SFC architectures. Based on this analysis, we propose a concept towards the fulfillment of the requirements while maintaining the flexibility of SFC. In addition, we provide and evaluate a proof of concept implementation, and discuss the implications of the design choices.

2021

Bradatsch, L., Kargl, F. and Miroshkin, O. 2021. Zero Trust Service Function Chaining. Conference on Networked Systems 2021 (NetSys 2021) (2021).

2019

Nägele, D., Hauser, C.B., Bradatsch, L. and Wesner, S. 2019. bwNetFlow: A Customizable Multi-Tenant Flow Processing Platform for Transit Providers. 2019 IEEE/ACM Innovating the Network for Data-Intensive Science (INDIS) (2019), 9–16.
Bradatsch, L. 2019. Anomaly detection based on traffic records. International Conference on Networked Systems (2019).

2017

Bradatsch, L., Lukaseder, T. and Kargl, F. 2017. A Testing Framework for High-Speed Network and Security Devices. 2017 IEEE 42nd Conference on Local Computer Networks (LCN) (2017), 506–509.

2016

Lukaseder, T., Bradatsch, L., Erb, B. and Kargl, F. 2016. Setting Up a High-Speed TCP Benchmarking Environment - Lessons Learned. 41st Conference on Local Computer Networks (Nov. 2016), 160–163. (acceptance rate: 33%)
There are many high-speed TCP variants with different congestion control algorithms, which are designed for specific settings or use cases. Distinct features of these algorithms are meant to optimize different aspects of network performance, and the choice of TCP variant strongly influences application performance. However, setting up tests to help with the decision of which variant to use can be problematic, as many systems are not designed to deal with high bandwidths, such as 10 Gbps or more. This paper provides an overview of pitfalls and challenges of realistic network analysis to help in the decision making process.
Lukaseder, T., Bradatsch, L., Erb, B., Van Der Heijden, R.W. and Kargl, F. 2016. A comparison of TCP congestion control algorithms in 10G networks. 41st Conference on Local Computer Networks (2016), 706–714. (acceptance rate: 28%)
The increasing availability of 10G Ethernet network capabilities challenges existing transport layer protocols. As 10G connections gain momentum outside of backbone networks, the choice of appropriate TCP congestion control algorithms becomes even more relevant for networked applications running in environments such as data centers. Therefore, we provide an extensive overview of relevant TCP congestion control algorithms for high-speed environments leveraging 10G. We analyzed and evaluated six TCP variants using a physical network testbed, with a focus on the effects of propagation delay and significant drop rates. The results indicate that of the algorithms compared, BIC is most suitable when no legacy variant is present, CUBIC is suggested otherwise.

2015

Frommel, J., Rogers, K., Brich, J., Besserer, D., Bradatsch, L., Ortinau, I., Schabenberger, R., Riemer, V., Schrader, C. and Weber, M. 2015. Integrated Questionnaires: Maintaining Presence in Game Environments for Self-Reported Data Acquisition. Proceedings of the 2015 Annual Symposium on Computer-Human Interaction in Play (London, United Kingdom, 2015), 359–368.
Research in human-computer interaction often requires the acquisition of self-reported data. Particularly concerning serious games, the interaction between the game and the user still holds many unknown aspects, partly due to the user's double role as player and learner. An easy way of collecting data consists of questionnaires, mostly employed in pen-and-paper or electronic form. In order to gather data points during game play, the player is interrupted, potentially causing unintentional side effects. We suggest an integration of questionnaires into games as game elements, in order to mitigate the effects of interruption. A serious game prototype with an integrated survey was implemented, and evaluated regarding its effects on the players' experience of presence.

2017

4.
Bradatsch, Leonard; Lukaseder, Thomas; Kargl, Frank
A Testing Framework for High-Speed Network and Security Devices
Proceedings of the 42nd IEEE Conference on Local Computer Networks (LCN)
Oktober 2017

2016

3.
Lukaseder, Thomas; Bradatsch, Leonard; Erb, Benjamin; van der Heijden, Rens W.; Kargl, Frank
A Comparison of TCP Congestion Control Algorithms in 10G Networks
Proceedings of the 41st IEEE Conference on Local Computer Networks (LCN), Seite 706-714
IEEE Conference on Local Computer Networks (LCN)
Dubai, UAE
7.-10. November
November 2016
DOI:10.1109/LCN.2016.121
2.
Lukaseder, Thomas; Bradatsch, Leonard; Erb, Benjamin; Kargl, Frank
Setting Up a High-Speed TCP Benchmarking Environment — Lessons Learned
Proceedings of the 41st IEEE Conference on Local Computer Networks (LCN), Seite 160-163
IEEE Conference on Local Computer Networks (LCN)
Dubai, UAE
7.-10. November
November 2016
DOI:10.1109/LCN.2016.32

2015

1.
Frommel, Julian; Rogers, Katja; Brich, Julia; Besserer, Daniel; Bradatsch, Leonard; Ortinau, Isabel; Schabenberger, Ramona; Riemer, Valentin; Schrader, Claudia; Weber, Michael
Integrated Questionnaires: Maintaining Presence in Game Environ- ments for Self-Reported Data Acquisition.
CHI PLAY 2015
2015