No traffic lights, no trains, no ATMs, no internet. The massive power outage this Monday, mainly in Spain and Portugal, paralyzed life across the affected countries. It is not yet clear what caused it and a cyber attack has not been completely ruled out.

In Germany, authorities have been making reassuring statements.

"A large-scale, long-lasting blackout is unlikely in Germany," said the responsible Federal Network Agency.

The German power grid is designed to be redundant, the agency explained. This means that if one line fails, another can replace it immediately.

But the uncertainty remains. How secure is the supply of energy and water, transportation, communication, health and financial services in Germany, or in other words, the critical infrastructure?

Germany also has grounds for concern: Last week, the Berlin Senate reported that there had been a cyberattack on the electronic service portal. The police force was also affected.

And these are just the most recent cases. Attacks on critical infrastructure occur repeatedly: Data cables in the Baltic Sea are damaged,........

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