High bit rate, high security
1 min read
Described as a ‘world record’ quantum cryptography bit rate, researchers at the Cambridge Research Lab of Toshiba Research Europe, have announced that it has increased the bit rate of quantum key distribution (QKD) more than hundred-fold.
QKD is a new technology for distributing secret digital keys on optical fibre and, unlike current algorithm based techniques, the secrecy of the keys formed by QKD can be tested and guaranteed. The Toshiba system uses a QKD protocol to form keys secure from all types of hacking on the communication channel. Because a secure key rate must be shared between many users, QKD has been hampered by its relatively low bit rate (typically less than 10Kbit/sec for a 20 km fibre link) which is too low for such networks. The new breakthrough will allow a 100 times increase to over 1Mbit/second for a 20km link, enabling use on networks with thousands of users. The Toshiba development team has also designed and implemented hardware in the first QKD network launched in Vienna, the product of a collaboration of 41 QKD R&D teams across Europe.
Head of Quantum Information Group at CRL, Dr Andrew Shields, commented: “Together, the dramatic increase in bit rate and the possibility of network deployment, herald a breakthrough in the applicability of QKD technology. We plan now to develop a fully functional prototype of the high bit rate QKD system for use in quantum networks.”
