BT first in QKD over hollow core fibre trial

Created September 13, 2021
Applications and Research

BT says it has achieved a milestone in the development of quantum-secure communications by conducting the world’s first trial of Quantum Key Distribution (QKD) over hollow core fibre cable, from Southampton University spin out, Lumenisity® Limited.

This summer, BT began trials of a new type of optical fibre – Nested Anti-Resonant Nodeless Fibre (NANF) hollow core fibre – at the BT Labs in Ipswich to test the potential benefits of deploying this technology for a variety of scenarios, including secure communications. The trials used cable developed and manufactured by Lumenisity to address the need for high-speed transactions and bandwidth increases in advanced communications systems, which has also been used for applications such as data centre interconnects (DCIs), edge and 5G xHaul.

In the latest trial, BT researchers successfully operated a state-of-the-art QKD system loaned by the EU OpenQKD project, using commercial equipment over a six-kilometre Lumenisity CoreSmart® cable with a hollow, air-filled centre, revealing potential benefits such as reduced latency and no appreciable crosstalk. Lumenisity’s cable also demonstrated further benefits for the deployment of QKD, as commercial telecommunications equipment will not need to be optimised in order to send a data-encrypted key. This is critically important because the equipment can be used normally without modifications, an issue that creates added complications for sending secure signals over standard fibre.

Professor Andrew Lord, BT’s head of Optical Network Research, said: “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.  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, said: “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.”

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This article was written
by Peter Dykes

Peter Dykes is a independent telecoms and technology journalist who has over that last 30 years written for a wide range of B2B publications and companies. A former BT engineer, he specialises in networks and associated support systems. He is currently Editor of Optical Connections.