Communication networks are ubiquitous in modern society. “This is something we are all familiar with, even if we don’t realize it,” says Dr. Pierre Meyer. “Whenever we go online, we communicate with other people.” Meyer is less interested in securing communication networks themselves, which he considers a mostly solved question, than in the possibility of performing secure computation within them. This becomes particularly challenging when the setting is no longer a trusted environment such as one’s own computer, where a program can simply be executed, but instead involves decentralized systems or cloud applications in which users exchange data. “What interests me is the question of whether I can give users a mathematical guarantee that they do not have to trust the service provider and that everything the provider does is exactly what they intended,” he explains. “Such a guarantee should also ensure that the provider does not use their data beyond the conditions they have specified.” This is the basic principle behind Secure Multi-Party Computation.
From Mathematics to Cryptography
Meyer came to this rather theoretical field of cryptography by a somewhat indirect route. “My curriculum, while not uncommon in France, differs from many of my colleagues in that I specialized in computer science very late. The year I switched from mathematics to computer science was the first year I produced research. After that, I stayed very much a discrete mathematician, but at the same time a mathematician with an interest in computer science,” Meyer explains. “I initially started working in graph theory because I thought it was much more accessible, due to the beautiful simplicity of its mathematical definitions. At the same time, I had always been interested in cryptography. I asked my professors about a natural interface between the two fields. They recommended that I look into cryptography as it is used in communication networks. Communication networks can be modelled using graph theory, which was the field I had been working in.” This topic has stayed with him ever since.
Secure Computation with as Little Communication as Possible
Meyer’s research takes a very fundamental approach. He investigates how secure computations can be carried out even when communication between the participating computers or individuals is limited. More specifically, he studies which cryptographic protocols can be developed for this purpose and how much communication is actually necessary. “Communicate as little as possible while still achieving what we need,” he says, describing one of the central challenges that drives his research. His work is deliberately theoretical: The concepts and ideas he develops are intended to pave the way for more efficient and practically applicable solutions in the future. One of the things that attracted him to CISPA is the combination of theoretical and applied cryptography. Here, he finds researchers working in both areas, creating an environment in which these perspectives can be brought together.
Science Across Borders
Given his educational background, Meyer is very familiar with the academic structures in France. He is now getting to know the structures in Germany better and, with them, the subtle differences within his discipline. “In my experience, France has traditionally taken a much more mathematically oriented approach to cryptography,” he says. “In Germany, you find a much stronger computer science perspective—probably due to the country’s strong engineering tradition. People here often place a great deal of emphasis on actually implementing algorithms, making them efficient, and running them in practice.” He wants to build on these different perspectives and bring people from both traditions together. “I am definitely interested in building some kind of cooperation network—with seminars, exchange programs, and similar activities—around the topic of Secure Computation,” the researcher says. Although this is still a rather tentative plan, it represents another major goal for him alongside establishing his own lab.
From Tourist to New Resident
Meyer has quickly settled into his new home in Saarland. And before his start at CISPA, he made a conscious effort to take time this summer to get to know his new home. “I came to Saarland a few weeks before my employment officially began so that I could explore the region as a tourist,” Meyer says. “Unfortunately, I arrived in the middle of the heatwave, so I didn’t travel as much as I had planned. But I got to know Saarbrücken very well instead. I really like the city.” He has also already found the perfect way to commute to his new workplace in St. Ingbert: a daily bike ride through the forest. Besides cycling, painting is what helps him clear his mind and relax. “For me, it’s not about becoming good at it, but simply about having fun. It gives me a great sense of freedom.”
