Design and Analysis of Communication Systems group University of Twente

Preparing communication networks for the future

The Design and Analysis of Communication Systems group at the University of Twente is a leading international research group in the field of wired and wireless networking, and internet measurement and security. Its aim is to contribute to a trusted and resilient internet.

At this moment, a staggering 84 percent of the world population owns a smartphone and 63 percent has private access to internet. In barely two decades, communication between people has taken on a whole new, digital dimension. The same digitisation also enables more and more communication between people and devices, like smart home applications, and between devices themselves, like autonomous cars and industrial robots. The research group Design and Analysis of Communication Systems (DACS) at the University of Twente aims to prepare digital communication networks for a future with ever-increasing demands.

The almost twenty-year-old group is presently led by professor Geert Heijenk and consists of about thirty people. ‘On the one hand, we investigate how to make networks more resilient against sudden disturbances like power failures’, tells Heijenk, ‘and on the other hand, we investigate how to make networks more secure against digital attacks, like DDoS.’
Heijenk himself is researching wireless communication between cars and between cars and the surrounding highway infrastructure to improve the future traffic flow of fully or partially autonomous cars. ‘The current autopilot of a Tesla car, for example, is very limited. In my opinion, autonomous driving can only be a real success when cars are able to communicate their plans with each other and with their surroundings.’
A relatively new line of research of the DACS group focuses on the ecological footprint of networks. Heijenk: ‘Some researchers have predicted that by 2030, ICT applications will be responsible for 21 percent of the power consumption in the world. And about one-third of that is accounted for by networks. So there is a world to be won if we can make networks more energy-efficient as well.’
One of the characteristics of the group is that it has quite a few researchers who work part-time at DACS, mostly one day per week, and for the remainder of the week at another organisation, like SIDN Labs, TNO, NCSC or at companies like Nedap and Northwave. Heijenk: ‘As a group, we have a strong focus on collaboration, both externally and internally. For example, many of our articles are not written by one PhD student and his or her supervisor, as is often the case in our field, but by a team of researchers from our group.’

Measure what happens

Another key characteristic of the DACS group is the strongly empirical nature of its research. Roland van Rijswijk-Deij is an associate professor in the group who specialises in internet measurement. ‘To understand how the internet works, it is not enough to look at the internet protocols used’, he says. ‘Humans run the internet, so you have to measure what actually happens on the web. We apply statistical and big data techniques to these measurement results to analyse the internet’s functioning.’
Van Rijswijk-Deij and his colleagues have operated the largest DNS measurement in the world since 2015, allowing them to distinguish important trends. ‘Some trends we have noticed are that an increasing amount of websites are hosted by fewer and fewer parties, that ever more parties have moved their email to the cloud, and that Microsoft has overtaken Google as an email provider.’
On a more fundamental level, the group analysed what happened when the security key of the Domain Name System was changed in 2018. Van Rijswijk-Deij: ‘Such a change is a very risky operation that can easily disrupt the internet usage of half the world. We have learned many lessons through our measurements on how such a key replacement can be done in the future with the least possible risk. Our ultimate ambition is to make the internet as safe and as reliable as drinking water from the tap. To do that, we need to map out the internet even better with measurements.’

Design of wireless networks

Assistant professor Suzan Bayhan works in the second main research branch of DACS: wireless networks and mobility. ‘I want to put resilience and energy efficiency into the core of the design of wireless networks’, she says. ‘We design better communication algorithms so that current and future applications can be served efficiently and with a lower energy footprint. Which users should be connected to which base stations? When should the network transmit data and when can it go to sleep?’ Bayhan and her colleagues also investigate the resilience of the Dutch cellular network infrastructure. ‘How robust is it against attacks? Where are its weak points?’
Before starting at DACS in 2019, Bayhan held research positions in Berlin, Helsinki and Istanbul, so she has some international places to compare. ‘What makes our group unique’, says Bayhan, ‘is that it examines communication networks in depth, from its wireless components at the edge to the protocols at its core. And it combines expertise in measurements, security, and wireless networks. This extensive scope made it very attractive for me to join the group. Another important aspect that I have noted from my very first contact with the group is that the academic environment is very supportive. There is a lot of emphasis on achieving diversity and inclusion. This is not just written on paper, but I really experience it myself.’

Group passport

Research field

network security, wireless networks and mobility

Institution

Design and Analysis of Communication Systems (DACS), Faculty of Electrical Engineering, Mathematics and Computer Science (EEMCS), University of Twente

Employees (as of May 2022)

3 full professors, 3 associate professors, 2 assistant professors, 13 PhD students, 7 part-time (assistant) professors / researchers.

Websites

Published in I/O Magazine #2 2022
Text Bennie Mols
Images Ivar Pel