BT begins trial on ‘revolutionary’ optical fibre

Even as the current generation of fibre-optic networks are being marketed as “future-proofing” broadband communications, UK telco BT is looking to the future of fibre and has announced research exploring how the capabilities of optical fibre can be enhanced with the potential to reduce the latency, or signal delay, by up to 50%.

The aim of the test is to surmount the limitations of traditional fibre. Networks across the world currently run on single-mode optical fibre, which consists of solid strands of glass.

Even though the glass in these cables quickly carries information over long distances by channelling light from laser transmitters through the glass strands, the fundamental nature of glass means that the light travels marginally slower inside the fibre than it would in air.

The new type of network cable has a hollow, air-filled centre that runs the entire length of the cable with an outer ring of glass, to guide the laser beam while maintaining the signal speed at very close to the ultimate speed of light. It will be used to test a variety of use cases, including potential benefits for 5G networks and ultra-secure communications, such as quantum key distribution (QKD).

Researchers at the BT Labs research and engineering campus in Adastral Park – where some of the pioneering work in fibre was carried out – are conducting the trials  using a 10km-long hollow-core fibre cable provided by Southampton University spin-out company Lumenisity, which was created to commercialise breakthroughs in the development of hollow-core optical fibre. Open radio access network (Open RAN) mobile supplier Mavenir is another partner in the project.

BT believes the reduction in the delay of the light provided by hollow-core fibre would enable various benefits, ranging from high-frequency trading to lowering mobile network costs. Working with Mavenir, BT says it has shown that using hollow-core fibre can increase the distance between street antennas and the back-end processing in exchanges.

In one example use case, due to its low latencies, use of hollow core in the radio access network (RAN) could reduce mobile network costs by allowing more 5G antennas to be served from one exchange or cabinet.

“We are excited to begin trialling hollow-core fibre and to discover the potential opportunities and benefits of deploying this technology in certain scenarios,” said Andrew Lord, BT’s head of optical network research. “This new type of fibre cable could play an important role in the future of the world’s communications infrastructure, heralding a step-change in capability and speed, to keep up with the demands for high-speed, low-latency communications driven by 5G networks, streaming, and more.”

John Baker, Mavenir’s senior vice-president of business development, added: “The ability to extend the reach of fibre-connected radios only further demonstrates the power of Open RAN and its ecosystem. This improvement will significantly increase the number of use cases that can be served from containerised cloud-based Open RAN solutions.”

The news comes just as Mavenir announced support for deployments and integration of cloud-native telecom network functions with telco infrastructure solutions on Amazon Web Services (AWS). The collaboration with AWS is designed to enable communications service providers to deploy Mavenir’s 4G and 5G products and applications with AWS’s computing infrastructure, container deployment and management technologies, and big data analytics services.