By Mark Jackson

Telecoms giant BT (EE) and Cambridge spin-outNu-Quantum today claim to have launched a ?world-firsttrial? of end-to-end quantum-secured communications for the newgeneration of ultrafast 5G mobile(mobile broadband)networks, which is being called AIRQKD (Air Quantum Key Distribution).

Quantum secure links are often said to be virtually ?un-hackable? becausethey rely on the use of single particles of light (photons) to transmit specialdata encryption ?keys?(QKD ? Quantum Key Distribution). Should this communication be intercepted, thesender will be able to tell that the link has been tampered with and the stolenphotons cannot then be used as part of the key, thus rendering the data streamincomprehensible to a hacker.

Last month BT and Toshiba succeeded in establishingthe UK?s first ?industrialdeployment? of a quantum-secure network using Openreach?s?standard?fibre optic infrastructure (here). The key rate of the QKD system ran atjust 1.1Mbps (each encryption key has a length of 256 bits), while theencrypted data link itself was running at 10Gbps (it can go to several hundredgigabits and at distances of up to 120km).

Meanwhile the new trial, which will run for 36-months, is being funded by aninvestment of ?7.7m fromthe Quantum Technologies Challenge, led by UK Research and Innovation. BTclaims it will be the first to combine QKD over fixed fibre and free-spacenetworks (point-to-point laser connections between cell sites), withquantum-enhanced security chips in mobile devices.

Apparently, both will be used to deliver an ultra-secure linkbetween connected 5G towers and mobile devices, as well as to connected cars,in conjunction with the Warwick Manufacturing Group at Warwick University.

Professor Andrew Lord, BT?s Head of OpticalNetwork Research, said:

?The UK has firmly established itself as a global leader inquantum-based network security. With the AIRQKD trial, we?re delighted to betaking this to the next level and combining multiple quantum technologies frominnovative UK start-ups to build the world?s most secure fixed-mobilecommunications link. Connected cars are only one of the possible range ofapplications that will benefit from such ultra-secure connectivity in thefuture.?

Dr Carmen Palacios Berraquero, co-founderand CEO of Nu Quantum, said:

?In this project, we are basically creating the architecture for awhole new quantum-telecommunication industry, with a supply chain running fromcomponent manufacture through to end user. At Nu Quantum we have the uniqueability to use the smallest packets of light, making the most of quantummechanics and the security advantage it can give us. This 3-year partnershipwith BT and others across the UK is an important step taking quantum out of thelab and into our networks.?

The AIRQKD projectinvolves the following partners: BT, Lexden Technologies, OLC, Duality, BristolUniversity, Fraunhofer Centre for Applied Photonics, Strathclyde University,Warwick University Manufacturing Group, Bay Photonics, Heriot Watt University,Angoka, ArQit, Nu Quantum, National Physical Laboratory, CSA Catapult,Edinburgh University.