The Echo Network

Mission 0: The Information Problem. Part of the Quantum Courier Service, a free course from the Oxford University Quantum Information Society.

Welcome to the QCS, Recruit. I wish your onboarding could be under better circumstances. For the last decade, our global communication lines were considered unbreakable. But yesterday, a highly sensitive dossier was intercepted by a shadowy syndicate. How we know that? Just let me show what we saw:

Here we go again with “The Echo Network”. The terrifying part? They didn’t break our vaults. They simply listened to the wires. The Echo Network has found a way to copy our data as it travels, leaving the original message perfectly intact. We had no idea they were listening until it was too late. Before we can teach you how to stop them using quantum tech, you need to understand how they beat us.

Your first mission: understand the nature of information, how it flows, and why classical secrets are never truly safe.