Cyber security

Encryption holds our digital society together

Man has been encrypting information since ancient times, but today it plays a bigger role than ever. In the future, our existing encryptions can easily be broken if we are not prepared.

DTU has one of only around 300 remaining copies of the German encryption machine, Enigma. Photo: Thomas Steen Sørensen

Many non-military enemies today

 Where encryption was previously primarily used by the military, it today reaches all corners of society, and this poses challenges.

“There are many more enemies today because we use cryptography in multiple contexts. The enemy may be your neighbour, who has found out that your network is not secure and then hacks it to discover what you’re doing,” says Tyge Tiessen.

Therefore, everyone from private companies to public authorities, banks, utility companies, and private individuals need encryption as a bulwark against hackers. And perhaps even against intelligence services—as whistleblower Edward Snowden’s revelations have shown, even law-abiding citizens risk being monitored, and communications services have therefore started using encryption which is virtually impossible to monitor.

Quantum computers change everything

In the future, however, all our encryption may be broken once we have quantum computers that can solve complicated problems where even the fastest supercomputers fail. It is a ticking bomb under our digital society.

"This is the period of transition to quantum-proof encryption,” says Assistant Professor Christian Majenz, who conducts research into precisely quantum encryption at DTU Compute.

“We’re trying to develop cryptography before the arrival of quantum computers, because otherwise they can be used to access all our existing data. But once we have found quantum-proof algorithms, it’s a bit like a Lego brick that you can build on.”


Highlights from the history of encryption

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Denmark is at the forefront when it comes to the use of technology and digital solutions. This brings about great opportunities – but also makes Denmark an obvious target for IT crime. Consequently, there is a great need for research and training in cyber security to ensure that technology continues to create value for people.


Read more in DTU's cyber security topic.