Fiber optic cables are essential for the operation of the Internet and interconnection around the world. Thanks to them it is possible to manage large amounts of bandwidth, and also in a secure way thanks to encrypted communications. However, the future of security has a new threat, and therefore they have created an immune cable to them.
BT, the British operator, has carried out the first test of the Quantum Key Distribution (QKD) through a hollow core fiber optic cable with a length of six kilometers. This new type of fiber optic cables are known as Nested Anti-Resonant Nodeless Fiber (NANF) , and its advantages include a lower latency and a practically total absence of interference between signals.
Hollow fiber cable
In traditional fiber optic cables, high-speed signals are transmitted through a fiberglass cable using different wavelengths that bounce off the walls of the cable. In systems with QKD , quantum light is transmitted in a single photon channel, usually requiring you to use another fiber cable next to it to avoid interference between communication channels, since they can overlap.
The hollow fiber does not have physical materials inside, but, as its name suggests, it only has air. As a result, the light is scattered less and goes more precisely to the destination. Thanks to this, the encrypted information can be sent over the same fiber cable together with the quantum signal with the encryption key without having to use two different cables. Therefore, it is the first secure cable that QKD uses without having to run two fiber cables side by side.
Prepared for the safety of the future
The cable, created by Lumenisity , also has other advantages for QKD deployment, since it is not necessary to optimize the current telecommunications equipment to send the encryption key. Thanks to this, there are no additional complications when sending encrypted content with fiber optic cables where the recipient may have problems decrypting the content.
With these advances, future fiber optic deployments will be able to be done at lower cost, as only one cable needs to be deployed instead of two. In addition, this helps us to be more protected in the face of new threats that will arrive when future quantum computers put the current encryption in check. In addition, they can help overcome current fiber speed limits.
A few months ago, Toshiba announced that their QKD project had managed to send signals over distances greater than 600 kilometers , but using the old system with two traditional fiber optic cables. Current commercial systems are limited to 100 or 200 km.
