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Top researchers share secrets – without disclosing them

PRESS RELEASE: When the world’s leading pioneers of cryptography meet at Aarhus University from June 4 to 8, 2012, there are not many secrets among the 120 participants. But the very purpose of the event is to discuss and challenge the increasing demand for being able to share secrets without disclosing them.

There is an increasing demand for being able to compute on data without looking at them, i.e. to enable multiple parties to exchange data without revealing more data than necessary. In popular terms: How to share secrets without disclosing them.

This week, professor of computer science, Ivan Damgård, and other top researchers and practitioners focus on the practical application of secure computations at the workshop Theory and Practice of Multiparty Computation.

- Thirty years ago it was hard to imagine that this would ever be practicable. But over time, researchers have found so many applications that I never would have dreamed of, says Ivan Damgård whose research field is ‘multiparty computation’, among other things. He is heading the CFEM project (Center for Research in the Foundations of Electronic Markets) at Aarhus University that organizes this event.

Sharing without revealing

The Multiparty Computation technology – to compute on encrypted numbers – started as basic research in the 1980s. Today the technology is applied in several contexts from social media to supply chain management and cloud computing.

One of the objectives of the workshop is to find additional practical applications in the world of finance.

– The fact that we can now perform these complex calculations within a few seconds instead of several days opens a whole range of new opportunities. And as a result of globalization, we also see a rise in the number of businesses that want to exchange data with other businesses, while at the same time being able to control exactly what they share. This is what this technology enables, says Ivan Damgård.

From basic research to business

The applications we see today are based on the findings from a number of auction research projects conducted in 2008. Jakob Pagter, Research and Innovation Manager of Security Lab at the Alexandra Institute, was part of the cryptography team at the Department of Computer Science at Aarhus University that was among the first to apply the theory in practice.

Today he is a partner in Partisia, which is a spin-off company resulting from the research projects. The company develops solutions based on Multiparty Computation for the energy marketplace energiauktion.dk, to mention but a few examples.

Cloud on the radar

As the technology becomes more efficient, Jakob Pagter hopes that it will be fast enough to enable cloud solutions.

- Cloud computing is a future application scenario. Many investigations show that security is the biggest concern in relation to cloud, Jakob Pagter points out.

- Cloud offers flexibility but in order to achieve that flexibility, the customer will have to relinquish control of his data. And this calls for maximum security. Multiparty computation will never be the only solution, but it does offer new opportunities, he says.

Even if your data is stored in a data warehouse in Brazil, they will remain encrypted, which is a considerable security advantage in practical applications as opposed to traditional solutions.

On the other hand, customers will get a reliable and inexpensive system. And they only pay for what they actually use. This is a very interesting perspective seen from a business point of view.

Meet Craig Gentry and other experts

Graig Gentry is world-famous for having solved an issue that has been open since 1980: Is it possible to perform so-called fully homomorphic encryption? If yes, it would be possible to perform random computations on encrypted data a lot easier and without additional communication. It was therefore big news when Gentry finally cracked the issue a couple of years ago. The answer is yes, it is possible. Today, researchers work on designing solutions that are also applicable in practice.


From June 4 to 8, Ivan Damgård and other Danish and international top researchers focus on practical application of secure computations at the workshop Theory and Practice of Multiparty Computation. The workshop is held at Aarhus University, IT City of Katrinebjerg, and is organized by CFEM in collaboration with the Sino-Danish research centre for the Theory of Interactive Computation (CTIC) and the Alexandra Institute.

Contact information

Professor Ivan Damgård, Aarhus University, Department of Computer Science, mobile: +45 2083 7137, mail: ivan@cs.au.dk.