Quantum Cryptography Record Broken!

Quantum Key Cryptography Research

John E. Dunn, Techworld.com

20/04/2006 08:06:00

Scientists have reported an important speed breakthrough which brings closer the day when quantum encryption becomes a usable part of communications security.

The National Institute of Standards and Technology (NIST), a U.S. government agency, has reported that it has managed to shift quantum-encrypted information at a "raw" throughput of 4 million bits per second across a 1 km-long fiber link.

This is at least twice NIST's previous record, which has been rising since the agency announced it had broken the 1 million bits per second barrier in May 2004.

At such transfer rates, it becomes practical to use quantum key distribution (QKD) cryptography to secure a video stream.

"This is all part of our effort to build a prototype high-speed quantum network in our lab," said NIST's Xiao Tang. "When it is completed, we will be able to view QKD-secured video signals sent by two cameras at different locations. Such a system becomes a QKD-secured surveillance network."

Despite sounding to non-initiates like a branch of mathematical magic, the benefit of quantum key distribution in communications is really the 100 percent certainty it offers that data has not been intercepted or tampered with as it moves between two points.

Anyone attempting to decrypt a photonic data stream encoded using such a system will -- as predicted by Heisenberg's oft-quoted uncertainty principle -- inevitably alter the state of the photons in a way that can be detected. This introduces a degree of verifiability impossible in conventional electromechanical encryption systems.

The agency reckons its test-bed demonstration will pave the way for the technology's use in specific applications such as military data transfer, or the transmission of sensitive financial and health-care information.

Despite the upbeat atmosphere, there is a way to go for QKD. The trade-off is still speed relative to distance, which at 1 km for the stated throughput is still too short a distance to have many practical applications. As NIST admits, other labs have managed further distances but at the cost of cutting data rates.

In 2003, a collaboration between a number of Japanese companies achieved distances of up to 100 km in tests.

In the U.K., the Cambridge Research Laboratory has demonstrated a working commercial system running at 25 kilobits per second over a distance of 122 km.

Quantum Cryptography

Quantum Key Cryptography Research

Quantum Cryptography

{Quantum Key Cryptography Research Advances and IBM Research May Extend Moore's Law}

The following MP3 tells how Quantum key cryptography researchers at the University of Toronto have described the first experimental proof of a quantum decoy technique to encrypt data over fiberoptic cable. Also, researchers at IBM have found a way to extend a key chip-manufacturing process to generate smaller chip circuits. (MP3, 2:57 mins.)

By Deirdre Blake, Dr. Dobb's Journal
Mar 01, 2006
URL:http://www.ddj.com/dept/security/184406426

Download should start automatically, if not, get MP3 file:

Quantum Cryptography

Public Key Cryptography Tutorial

Quantum crypotography

There is growing interest in using quantum cryptography for commercial and military applications because of the technology's apparent ability to guarantee invulnerability.

Before jumping into Quantum Cryptography's exciting possibilities, a person must understand what exactly this technology is and what exactly it does and could do soon.

Quantum cryptography uses quantum physics for secure communications. Unlike traditional cryptography, which employs various mathematical techniques to restrict eavesdroppers from learning the contents of encrypted messages, quantum cryptography is based on the physics of information. Eavesdropping can be viewed as measurements on a physical object — in this case the carrier of the information. Using quantum phenomena such as quantum superpositions or quantum entanglement one can design and implement a communication system which can always detect eavesdropping. This is because measurements on the quantum carrier of information disturbs it and therefore leaves traces.

Quantum crypotography R&D has been fast paced. According to the Technology Research Review -- 2004

A pair of security research developments made it apparent that quantum cryptography, unlike quantum computing, is within a few years of prime time. Quantum cryptography has the potential to provide perfectly secure communications.

On April 21, researchers from the University of Vienna in Austria, ARC Seibersdorf Research GmbH in Austria, the University of Munich in Germany, and the Austrian Academy of Sciences transferred a secret encryption key

And BBN Technologies, Harvard University and Boston University researchers built a six-node quantum cryptography network designed to operate continuously to provide a way to exchange secure keys between BBN, Harvard and Boston University. Previous quantum cryptography systems sported only point-to-point connections.

Quantum crypotography certainly has a bright future. Due to it's apparent invincibility, both commercial and military applications for this amazing new technology are exciting to think about.

Quantum crypotography