“I always try to bear in mind that people are very diverse”

Around 1995, Jean-Yves Le Boudec was walking through the streets of San Francisco and saw an internet address on a billboard advertising a pizzeria. He says, “I was fascinated to see a private business using something I’d only previously seen in academia.” Prof. Le Boudec, the head of EPFL’s Laboratory for Communications and Applications 2, has seen his field of research and teaching change radically over the years as the internet has grown in popularity. “I teach a subject that’s always changing, although the basic concepts – the key ideas – remain the same.” Le Boudec is a big fan of Wikipedia, which he regards as “the web’s greatest invention.” Yet he believes that the wide accessibility of information means that his course “had better be good” if it’s to be worth taking. Mission accomplished: he has been awarded this year’s prize for best teacher in his section.

Prof. Le Boudec, who came to EPFL in 1994, designed the School’s first communication systems study program. He specializes in deterministic networking, which involves networks that ensure strict quality of service. Simply put, these networks guarantee that a packet of data is sent in a few milliseconds, regardless of the state of the network. He is currently working with Huawei on 5G technology and has contact with Airbus to enhance IT service quality onboard its aircraft.

Diverse points of view

Jean-Yves Le Boudec, a native of Brittany, France, is one of seven children born to working-class parents. He first became interested in communication systems through his brother, a radio engineer four years his elder. He used to share a bedroom with that brother, and the two remain very close. But before delving into the world of networks – surrounded by cables and large, expensive computers – Prof. Le Boudec first studied mathematics. Rached Mneime, a lecturer at Ecole Normale Supérieure de Saint-Cloud, encouraged him to study algebra. “Studying under him was a revelation: everything became crystal clear,” says Le Boudec.

Prof. Le Boudec then completed a PhD in mathematics at the University of Rennes. He started teaching at the start of his doctoral studies. “I was 22 years old, teaching math to high-school literature students in their final year,” he says. “I tried to explain things as best I could, but at the end of the class two girls came up to me and told me they hadn’t understood a word. I was really surprised. Since then, I’ve always tried to bear in mind that people are very diverse. Everyone sees things differently.”

In his Master’s-level TCP/IP Networking course, Prof. Le Boudec focuses on the “why” in order to help students understand the “how.” That way, students can develop their own mental image of how network communication and architecture are organized. To help them get to grips with the subject over time – and avoid any end-of-year panic – he tests their knowledge every two weeks. “This seems to work,” he says. “The students absorb more of what I’m teaching, their questions are more relevant, and I can identify any problems.”

He also uses peer learning. Every 20 minutes in class, Prof. Le Boudec asks a few questions that students can answer using clickers or the SpeakUp app. He then instructs the students to explain to each other why they gave the answers they did. “Initially, there’s a wide range of wrong answers, but after a discussion the right answer almost always emerges.” This method – which requires a lot of preparation, particularly when devising the questions – has also proven effective in Le Boudec’s other Master’s courses, on performance evaluation and smart grid technologies, which he teaches with Mario Paolone. The latter course is closely connected to one of Le Boudec’s research areas: IT networks that control energy distribution and manage, for example, excess solar energy production in summer.

To ensure his students can test out the concepts they are learning, Prof. Le Boudec links theoretical teaching with exercises and practical work, using an open approach. And to take into account the varying ways in which students assimilate knowledge, he makes video recordings of all his classes available on YouTube, and all supporting materials available on Moodle. “If you have the time to do it properly, teaching is a joy. If you don’t, it can be hell!” he jokes. Nevertheless, this father of four children – one of whom is now an EPFL student – has always loved teaching. As the head of his section, a position he has occupied several times, he introduced the systematic assessment of teaching staff. “It can’t be the only thing you look at,” he says. “But it’s like a smoke detector – if a course is going badly, it will tell you.” What is the best compliment he ever received? “A member of the cantonal government once told me that my course left a lasting impression on him. I want my teaching to be of long-term use to our graduates.”