BT demonstrates quantum-secure communication on revolutionary hollow core fibre cable
Trial of quantum key distribution over HCF cable is a 'world's first', BT claims
BT announced on Monday that it has achieved a new milestone in the development of quantum-secure communications by completing the 'the world's first' trial of quantum key distribution (QKD) over hollow core fibre (HCF) cable.
The company conducted these trials at BT Labs in Adastral Park, Ipswich, in association with Lumenisity Ltd, a Southampton University spin out firm, and American Open Radio Access Network (O-RAN) mobile vendor Mavenir.
BT claimed that its research team was able to operate a QKD system over a 6-km-long Lumenisity CoreSmart cable, demonstrating HCF's potential benefits such as reduced latency (signal delay) and no appreciable crosstalk.
QKD is a protocol used to establish an ultra-secure communication channel during the transmission of light particles over a network. It enables two communicating parties to agree on an encryption key and use it to encrypt the messages transmitted over an insecure channel.
The QKD protocol can provide security against even the most arbitrarily powerful eavesdroppers, based on the fact that any attempt by an attacker to measure a quantum system will eventually disturb the entire system. In other words, an eavesdropper trying to intercept a quantum exchange will leave traces that can be easily detected by the legitimate communicating parties. As the two parties are alerted about the intrusion, they can abort the session and start a fresh one to exchange information.
BT started its trial of Lumenisity's CoreSmart cable in June, saying that it would use this new type of fibre-optic cable to test a variety of use cases, including potential benefits for 5G networks and ultra-secure communications, such as Quantum Key Distribution (QKD).
Unlike a traditional optical fibre cable, which is made from solid strands of glass, an HCF cable features a hollow, air-filled central core, with an outer ring of glass, which runs the entire length of the cable. Because HCF's central core is filled with only air, there is less light scattering and reduced crosstalk between channels.
BT said that the use of HCF in a Radio Access Network could also potentially reduce costs by allowing more 5G antennas to be served from one exchange or cabinet.
"This is an exciting milestone for BT, accelerating the UK's lead in quantum technologies that will play an important role in future communications systems globally," said Professor Andrew Lord, BT's head of optical network research.
"We've proven a range of benefits that can be realised by deploying hollow core fibre for quantum-secure communication. Hollow core fibre's low latency and ability to send QKD over a single fibre with other signals is a critical advancement for the future of secure communications."
Tony Pearson, VP Sales and Marketing at Lumenisity, stated: "We are excited to be identifying new applications for our field deployable CoreSmart cable solutions and working with the BT team on the first trial in the world of this kind."
"This milestone further accentuates not just the capability of our hollow core cable solutions, offering low latency and high bandwidth, but also demonstrating the potential CoreSmart has in new applications thanks to ultra-low non-linearity and dispersion across a broad spectrum, perfect for networks operated by our Carrier partners."