Australian quantum cybersecurity company leverages known “flaw” in diode to measure quantum noise to build stronger cryptographic keys
San Jose, Calif. – February 14, 2018 – When it comes to security, the term “tunneling” typically isn’t a positive thing as you tend to think about criminals getting around your defenses. But QuintessenceLabs, an Australian cybersecurity company using quantum physics to build stronger data security tools, sees tunneling as a good thing. The company leverages an intriguing quantum property in diodes, called quantum tunneling, to power its next generation of “qStream”, their quantum random number generator (QRNG), and improve data protection by generating stronger encryption keys.
Quantum tunneling is a phenomenon in which a particle travels across a barrier that—according to classical mechanics—it should not be able to cross. Quantum tunneling results in random fluctuations in the current flowing through the tunnel diode since there is no way to determine beforehand how many charge carriers would “tunnel” through at any instant time. QuintessenceLabs has developed a patent-pending way to measure and digitally process these fluctuations to generate “full-entropy” random numbers in its next-generation qStream at a very high rate of 1Gbit/s.
“It is surprisingly hard to generate true random numbers at speeds fast enough for commercial use, which is why most applications have relied on deterministic – or pseudo-random numbers. Unfortunately, you only find out just how fragile pseudo numbers are when it’s too late and a breach occurs” said QuintessenceLabs Founder and CEO Vikram Sharma. “Cryptographers understand the need to take that issue out of the equation. QuintessenceLabs offers a real answer to the problem through innovations in quantum physics applications.”
Tunneling for Stronger Encryption with the Esaki Diode
Tunnel diodes, one of the most commonly used negative resistance devices, are also known as Esaki diodes named after Leo Esaki, who received the Nobel Prize in Physics in 1973 for discovering the electron tunneling effect used in these diodes.
A tunnel diode, under reverse bias, forms a carrier depleted barrier that, according to Newtonian (or classical physics), charge carriers cannot cross if they have an insufficient amount of energy to do so. In the quantum world, this additional energy to overcome the potential barrier is not necessary, some of the particles will instead “tunnel” through it. In other words, Quantum tunneling enables particles to cross a potential barrier when there is insufficient energy to overcome it. The number of particles that will tunnel through in each instant of time cannot be predicted, making the effect an ideal source of entropy for generating random numbers.
Many others have used these diodes for various applications such as high-frequency oscillators and microwave amplifiers, but QuintessenceLabs has developed a unique way to use Esaki diodes to power a robust QRNG and replace the pseudo-random number generators (PRNG), typically found in most security applications.
PRNGs generate numbers using a short random seed based on deterministic algorithms. Although widely used in modern digital electronic information systems, pseudo-random numbers have resulted in many security issues making the underlying encryption vulnerable. With qStream, you can eliminate this downside.
qStream generates true random numbers both at high-speed and at the highest quality, two things that until now have not been possible from one device.
Move Over Lasers
QuintessenceLabs launched its first generation of qStream device in 2015 using lasers as the source of its quantum random number generation before switching to quantum tunneling.
Tunnel diodes can generate full entropy random numbers at the same rate as the first generation, but without the need of laser and photo-detector. The new design results in a more compact and cost-effective product, cutting the size of the QRNG hardware to a quarter, while delivering the same quality and speed.
“Our initial concept worked flawlessly, but we are always looking for better ways to get the same or improved results,” added Sharma. “We have been exploring other methods, besides lasers, for a few years. Tunnel diodes looked promising, but we had to find a way to accurately measure and digitize the information in a way we could use for our purposes. The team has been pushing the boundaries on this for over a year to refine the technology for commercial use.”
The QuintessenceLabs quantum random number generator “qStream” is compliant with NIST SP 800-90A and meets the requirements of the draft NIST SP 800 90B and C. It is delivered as a standalone appliance or as part of its Trusted Security Foundation® (TSF®). QuintessenceLabs has partnered with PKWARE to offer end-to-end data protection solution from quantum key generation and management through end-point encryption, as part of the PKWARE’s line of Smartcrypt appliances.