Europe Region

Main Menu


Committed to People, Committed to the Future. Toshiba

Toshiba Research Europe Ltd., Cambridge Research Laboratory

Quantum Information Group, Toshiba Quantum Key Distribution System

Image: Quantum Key Server consists of two compact boxes designed to fit into a communications rack.

Toshiba's Quantum Key Distribution System delivers digital keys for cryptographic applications on fibre optic based computer networks. Based on quantum cryptography it provides a failsafe method of distributing verifiably secret digital keys, with significant cost and key management advantages.

The system provides world-leading performance. In particular, it allows key distribution over standard telecom fibre links exceeding 100 km in length and bit rates sufficient to generate 1 Megabit per second of key material over a distance of 50 km — sufficiently long for metropolitan coverage.

Toshiba's system uses a simple ‘one-way’ architecture, in which the photons travel from sender to receiver. This design has been rigorously proven as secure from all types of eavesdropping attack. This ensures that the Toshiba design will be secure not only today, but also in the future.

Toshiba has pioneered active stabilisation technology that allows the system to distribute key material continuously, in even the most challenging operating conditions, without any user intervention. This avoids the need for recalibration of the system due to temperature-induced changes in the fibre lengths. Initiation of the system is also managed automatically, allowing simple turn-key operation. It has been shown to work successfully in several network field trials. The system can be used for a wide range of cryptographic applications, e.g., encryption or authentication of sensitive documents, messages or transactions. A programming interface gives the user access to the key material.

Further Reading

  Type Title and author(s) Source
1 Technical Continuous operation of high bit rate quantum key distribution
by A R Dixon et al.
Applied Physics Letters 96, 161102 (2010)
Download preprint
[preprint is open access]
2 Easy Key to the Quantum Industry
by A Shields and Z L Yuan
Physics World 20, 24 (2007)
[free registration required
to view full text]
3 Technical Practical quantum key distribution over 60 hours at an optical fiber distance of 20 km using weak and vacuum decoy pulses for enhanced security
by J F Dynes et al.
Optics Express 15, 8465 (2007)
[open access]
4 Technical Continuous operation of a one-way quantum key distribution system over installed telecom fibre
by Z L Yuan and A Shields
Optics Express 13, 660 (2005)
[open access]
5 Easy Light holds the key
by Roger Dettmer
The IEE Review 7, 32 (2005)
6 Technical Quantum key distribution over 122 km of standard telecom fibre
by C Gobby, Z L Yuan and A J Shields
Applied Physics Letters 84, 3762 (2004)
Link to Quantum Information Group - Quantum Cryptography Solutions for Network Security
Link to Speech Technology Group
Link to Toshiba Fellowship Programme - Join Toshiba's R&D team in Japan for up to two years
Terms and ConditionsPrivacy Policy Copyright TOSHIBA Corporation, All Rights Reserved.