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Sterre den Breeijen, self-sovereign identity portfolio manager

Sterre is always curious. Being curious is a basic attitude that’ll get you far at TNO, and it’s what makes Sterre such a good portfolio manager and consultant. Self-sovereign identity (SSI) is one of her specialities.

‘When people ask me what SSI is, I prefer to give them an example. When someone wants apply for a mortgage, the mortgage lender has to request information from the bank, tax administration, valuer, Credit Registration Office, and so on. That’s a lot of work. Once the documents have been supplied, the mortgage lender simply has to assume that they’re authentic.

SSI technology, however, can quickly and safely complete a mortgage loan application in less than three minutes. The ‘wallet’ knows what information the mortgage lender needs and, with your permission, automatically collects it from you. The principle is that you manage your own information, and can share it when, with whom, and for what purpose you want. The information you provide is authentic and reliable for third parties. This results in lightning-fast decision-making processes, which in turn lead to tremendous savings and satisfied users.’

Where are we heading?

‘In my role as portfolio manager, I’m responsible for developing TNO’s SSI roadmap. Where would we like to be regarding the technology in five or ten years? I evaluate which projects contribute to the department’s strategic goals, and those of TNO as a whole. What do we want to accomplish with SSI? I was always asking these kinds of questions, even when I was “just” a scientist. When the portfolio manager was looking for a successor, I knew it was the job for me.’

Decentralised architectures

‘I combine my work as a portfolio manager with my role as a decentralised architectures consultant. The projects I contribute to in this role are concerned with data sharing and digital identity, in other words much broader fields than SSI. A lot of technology is already available, and we’ve tested various applications. The next step is to bring together stakeholders for successful collaboration in an ecosystem.’


‘I began studying cryptography during my master’s degree in mathematics. I wanted to do research; invent new things. Not for other mathematicians, but for ‘ordinary’ people, who would really benefit from them. My preference, therefore, was not to work in a company’s R&D department, because your scope is limited. In the Netherlands, this means you quickly end up at TNO, where research is both independent and applicable. Just over three years ago, a vacancy for cryptographer suddenly opened up.’


‘Many employers have a relatively fixed trajectory for the first year. Things are very different at TNO. You quickly discover there are countless opportunities to pursue your own path, just as long as you’re curious (which I am). Being interested in so many areas, I’ve never wanted to specialise. I’m open to a wide range of topics and types of projects, and I really enjoy discussing them with colleagues. And before you know it, you find yourself participating in a really interesting project.’



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Self-Sovereign Identity (SSI) offers citizens new ways to manage their privacy, eliminate the need to log in with passwords, and speed up transactions over the Internet and in real life. In addition, SSI... Read more
Our work

eSSIF-Lab: Help shape a safe and secure Next Generation Internet

On 1 November 2019 the EU Cascaded Funding project ‘eSSIF-Lab’ (European Self-Sovereign Identity Framework Lab) has started. In this project, EU funds will be made available to European corporations,... Read more
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