- Optical research expert says quantum computers could crack current public-key cryptosystems within a few years.
- Ubiquitous fibre connectivity particularly vulnerable to attack.
- BT sees QKD — “fighting quantum with quantum” — as key in safeguarding national critical infrastructure.
Andrew Lord, Senior Manager of Optical Research at BT, outlined a doomsday scenario timeframe for national critical infrastructure, governments, and the internet if quantum computing becomes too powerful, too soon, before adequate security countermeasures are developed.
In a recent presentation hosted by University College London (UCL), as part of a series of “Quantum Talks” organised by UCL’s Quantum Science and Technology Institute, Lord unveiled a slide — internally produced by BT — under the ominous headline of “The Quantum Apocalypse”.
According to BT’s estimates shown on the slide, the ability of quantum computers to hack a 2048-bit RSA (Rivest–Shamir–Adleman) public-key cryptosystem, “in a matter of hours”, could happen as early as 2024 or 2025. Classical computers, he reminded his audience, would need “billions of years” to crack today’s cryptosystems for distributing keys.
The 2024–2025 timeframe is on the assumption that the power of functioning quantum computers grows relatively fast. Factor in more conservative growth projections, and the Quantum Apocalypse, sometimes referred to as “Q‑Day”, might be delayed on BT’s timescale until 2038.
“We’re hedging our bets”, admitted Lord, although he felt Q‑Day would probably happen sooner rather later given the “billions of dollars investment” being funnelled into quantum computing research. “I’m not sure we even know… the full extent of how that development is going”, he added, “but it only needs one or two breakthroughs in the base technology to accelerate those curves”.
The urgency to develop adequate security measures is all the more pressing, insisted Lord, since “millions of kilometres of fragile fibre are vulnerable around the world”. With the right care and attention, aided by equipment costing only tens of dollars, Lord described how it was possible to bend fibre and let light escape. In this way, data can be read, or even stored for study and decryption at a later time. “This is not a trivial problem”, said Lord. “We’ll be at risk in a few years’ time”.
Quantum of solace
‘Quantum Apocalypse’ is not a BT coinage. It is a concept that has been around for some time, but by revealing possible (and early) Q‑Day timescales, Lord clearly wants to focus industry minds.
He ruefully pointed out that his slide showing latest developments in quantum computing was regularly in need of updates, referencing the launch of Honeywell’s “newest generation quantum computer” in October 2020 — not on Lord’s UCL slide-deck — which will initially offer ten “fully‑connected” quantum bits (qubits). Although well short of the number of “genuine and fully entangled qubits” needed to hack 2048‑bit public-key cryptosystems — in excess of 1,000 qubits, according to Lord — quantum computing is now emerging from the lab, where some spectacular results have already been achieved.
In late‑2019, a leaked paper reported by news outlets and science journals showed that Google had achieved “quantum supremacy”. By harnessing 54 qubits to perform a random sampling calculation — essentially verifying that a set of numbers is randomly distributed — Google’s prototype quantum computer was apparently done and dusted with the problem in a matter of minutes. Google later confirmed the contents of the leaked paper, and stood by its claims that the same calculation would have taken IBM’s Summit, the world’s most powerful supercomputer, 10,000 years.
QKD: fighting quantum with quantum
Lord said BT has been conducting quantum key distribution (QKD) trials since 2014, starting out in collaboration with Toshiba Research (BTwatch, #254, #270, #280, and #287). For him, QKD is “provably secure” against powerful quantum computers.
“With QKD, the key is refreshed constantly, making it impossible to hack into the key during transmission”, explained Lord. “The system is innately secure if you set it up properly”.
The challenge remains, however, of extending QKD implementations beyond the bespoke point-to-point connections in pilots, to support international communications and, ultimately, enable a secure quantum internet.
The industry vision, as BT sees it, is to have QKD extend from 5G access through to the metro transport layer, and then onto the photonic core. Lord was not clear if all this could be in place before a possible Q‑Day in 2024, but he seemed optimistic that satellite-enabled QKD would be “commercial reality” within two years. By using satellites and ground stations to distribute keys — in conjunction with fibre distribution — Lord envisaged “global” QKD reach.
He gave an example of a large oil company being able to securely connect its rigs around the world, but cautioned, somewhat worryingly for those thinking that Q‑Day is nigh, that industry is “nowhere near this”.
Lord told BTwatch in September 2020 that extensive commercial deployment of QKD in BT’s metro and core networks was at least five years away (BTwatch, #316).
QKD on trial
Lord claimed BT leadership in QKD research, in terms of coordinating work with suppliers. Aside from Toshiba, vendor partners including ADVA and ID Quantique have featured prominently. Highlights include:
- In partnership with Toshiba Europe, BT in October 2020 announced deployment of a “quantum-secure network” to transmit data between two sites in northern Bristol: the National Composites Centre, a composite research and development hub; and the Centre for Modelling & Simulation, a digital engineering research organisation. The proof-of-concept tested integration of QKD with OSA Filter Connect, a commercially available wave division multiplexing (WDM) fibre product provided by Openreach and developed by longstanding partner ADVA (BTwatch, #295).
- In June 2018, BT flagged the construction of the UK’s “first” QKD‑secured, high‑speed fibre network, which runs between BT Labs in Adastral Park and Cambridge University (BTwatch, #297 and #304). Stretching over a distance of 120km, and across a standard fibre connection through multiple BT exchanges, the link was built by BT, the University of Cambridge, and the University of York. It was co‑funded by the Engineering and Physical Sciences Research Council. Suppliers in the mix included ADVA, which provided a dense wave‑division multiplexing fibre network and ID Quantique, which provided commercial QKD gear.
- In September 2019, BT was flagged as one of the UK participants in a Europe‑wide quantum communications research project (BTwatch, #307). The OPENQKD pilot is funded through the European Union’s (now-defunct) Horizon 2020 initiative, and was slated to examine the application of QKD technology in various areas, including electricity supply chains, government services, healthcare, and, particularly, telecoms security. Along with existing QKD research partners in the UK (Toshiba Research, the National Physical Laboratory, and the University of Cambridge), BT’s role included the provision of systems and network expertise building on collaborative work already undertaken by the partners. Work linking biotechnology labs conducted by BT, the University of Cambridge, and Toshiba was also expected to contribute towards the development of healthcare use‑cases as part of the project (BTwatch, #255, #297, and #304).
Although BT, naturally enough, is primarily interested in quantum communications, Lord’s UCL presentation flagged other areas of note (see table).
He gave special mention to quantum computing. “From a telco perspective, that’s the kind of thing we could offer as‑a‑service to customers that can’t afford their quantum computer in the future, but might want network access to something secure”, he said.
As almost an aside at the end of his presentation — no doubt because of time constraints — Lord flagged the need for quantum specialists and network engineers to work closer together. This seemed all too clearly illustrated in the fact that it was not yet decided on which layer of the seven-level Open Systems Interconnection Model that QKD should sit.
|Fields of quantum||Applications||BT activities/aims|
Sources: BT, BTwatch.
|Quantum clocks and timing||
Orders of magnitude more accurate than atomic clocks with a wide range of prospective applications across sectors including finance, transport, telecoms, and energy, with implications for critical national infrastructure.
Looking beyond GPS‑based network synchronisation and examining real‑world application of quantum timing technology.
Part of the Europe‑wide integrated quantum clock (IQClock) consortium.
Quantum imaging systems build a picture of the environment, including 3D. Potential applications include military and law enforcement, along with driverless cars, search and rescue, infrastructure monitoring, and maintenance.
Infrastructure monitoring and maintenance most likely of interest to BT.
|Quantum sensing and measurement||
Quantum sensors have higher sensitivity, accuracy, and speed, resulting in sensitive magnetic field and gravity use cases. Potential applications in resource management, manufacturing, heath, and telecoms.
Lord says BT has looked at the possibility of using highly‑sensitive quantum sensors to detect where cables are, and how they might be used to warn operations teams when equipment is at risk of failure.
|Quantum computing and simulation||
Advanced problem‑solving and modelling to analyse and tackle problems unaddressable by conventional computers. This is ideal, says Lord, for BT and its customers that deal with high volumes of data and different parameters. Network planning, field force planning, resource optimisation, and simulation are some of the potential applications.
No explicit activities other than a desire to offer quantum compute as‑a‑service in the future.
Cryptography, emphasises Lord, underpins security of financial, business, government, and personal communications. Some forms of encryption in use today are vulnerable to attack by future quantum computers. QKD is the only “provably secure” option today, maintains Lord, leading to opportunities for providing “ultra-secure networks communications”.
Conducting QKD trials in the UK with various partners, including ADVA, ID Quantique, and Toshiba.