Via Photonics, Secure Communications

Quantum key distribution as well as emerging techniques that harness temporal cloaking and optomechanical crystals vie for securing optical communications.

HANK HOGAN, CONTRIBUTING EDITOR, [email protected]

Much of the world’s communications travel by light. So, data carried on photons moving through free space or over fiber must be made as secure as possible. Quantum key distribution helps do that. Also, security improvements via temporal cloaking and optomechanical crystals are on the horizon.

However, even when these and other new methods are deployed, there will still be gaps in the data armor. For that reason, a layered defense is best, such as the use of multiple levels of encryption, said Gregory Kanter, CEO of Evanston, Ill.-based NuCrypt LLC. The company was founded to commercialize a high-speed optical encryption device and now supplies quantum optics products.

Security involves trade-offs. Consider free space optics, with a transmitter and receiver communicating over a light beam. That configuration can enhance security.

“Typically, the eavesdropper has to be physically in the line of sight,” Kanter said.

Thus, if the beam has a small cross section, it can be difficult and expensive for an attacker to intercept. The downside, though, is that a tighter beam is harder to align, making it more difficult to use.

Something similar happens with optical fiber. It must be physically tapped, and that can be detected by, for instance, sending a signal down the line and looking to see if some unexpected result comes back. In practice, though, the system must be designed with margin, which makes spotting anything but a big tap difficult. What’s more, this assumes a network is completely clean of unwanted or unknown taps to begin with. That may not be a safe assumption in today’s world, according to Kanter. Thus, if the beam has a small cross section, it can be difficult and expensive for an attacker to intercept. The downside, though, is that a tighter beam is harder to align, making it more difficult to use.

Member Exclusive: To read the complete article, please Login or Register

Published: June 2017

Glossary

quantum key distribution: Quantum key distribution (QKD) is a method of secure communication that utilizes principles from quantum mechanics to establish a shared secret key between two parties, typically referred to as Alice and Bob, while detecting any potential eavesdropping attempts by a third party, commonly known as Eve. The fundamental principle behind QKD is the use of quantum properties, such as the superposition principle and the no-cloning theorem, to enable the distribution of cryptographic keys in a...
freeform optics: Freeform optics refers to the design and fabrication of optical surfaces that do not follow traditional symmetric shapes, such as spheres or aspheres. Unlike standard optical components with symmetric and rotationally invariant surfaces, freeform optics feature non-rotationally symmetric and often complex surfaces. These surfaces can be tailored to meet specific optical requirements, offering greater flexibility in designing optical systems and achieving improved performance. Key points about...
nonlinear optics: Nonlinear optics is a branch of optics that studies the optical phenomena that occur when intense light interacts with a material and induces nonlinear responses. In contrast to linear optics, where the response of a material is directly proportional to the intensity of the incident light, nonlinear optics involves optical effects that are not linearly dependent on the input light intensity. These nonlinear effects become significant at high light intensities, such as those produced by...
packet switching: The transmission of data in groups (packets) of information~comma~ each handled as an aggregate.

Browse Cameras & Imaging, Lasers, Optical Components, Test & Measurement, and more.