In 2013, Edward Snowden, a U.S. National Security Agency contractor, leaked documents showing that intelligence agencies were spying on the data of private citizens. One disturbing fact was that the spies tapped into optical fiber cables to access the huge amount of data moving through these cables.

Snowden’s disclosures pushed researchers to use quantum science to make this type of hacking impossible. Finally, there are reports of progress.

THE QUANTUM KEY DISTRIBUTION APPROACH

A startup called Quantum Xchange will access 500 miles of optical cable along the Eastern U.S. coast. Quantum will use this cable to create the country’s first quantum key distribution (QKD) network.

Quantum Xchange’s “QKD approach” would send an encoded message in bits while transmitting the decoding keys as quantum bits, or qubits. Usually in the form of photons, the qubits travel easily along fiber cables. However, any attempt to spy on a qubit would instantly destroy its fragile quantum state, erase any data and leave the mark of an intrusion.