(LaserFocusWorld) Being able to take advantage of existing underground fiber networks to transmit entangled photons is essential for deploying practical quantum-key distribution (QKD) systems, which will create encryption keys for secure communication that is resistant to all computational hacks.
That is the reasons the technique demonstrated by researchers at the National University of Singapore (NUS) and Singtel (both in Singapore) is so important. Together, they were able smoothly navigate these networks with entagled photons. Most QKD schemes require that the sender and receiver of a secret message exchange photons directly or trust the source of their keys. With this alternative approach, it is possible to check the security of a key provided by a third-party supplier.
In showing it can work, the team boosts expectations for QKD over commercial fiber.