Toshiba’s QKD system has been successfully demonstrated on the Quantum Xchange (QXC) Phio network – connecting the financial markets on Wall Street with back-office operations in New Jersey.

Banks and financial institutes have some of the most demanding IT and data security requirements. They need to ensure real-time availability of data for banking transactions and applications, while at the same time protecting sensitive client and proprietary information. In addition, they are subject to increasing levels of evermore stringent compliance and regulatory requirements.

Banks and financial institutions need to be able to transfer data securely from their data processing and recovery centers, to their campus networks for real-time trading and transactional data exchange, to core banking applications and video conferencing over their wide area networks.

Quantum Xchange’s ultra-secure, quantum network is used to securely transmit high-value data, including trading algorithms and customer settlement accounts, for several large banks and asset.

Toshiba QKD enabled Quantum Xchange to transmit a live, uncompressed video stream along with the QKD traffic between New York and New Jersey over a single fiber. The link was used because we wanted to prove that the system worked on a live network. Until that time, Quantum Xchange had never been able to get QKD systems to work over that distance due to technical issues. The trial was designed to ensure the system could support the needed distance and delivery requirements demanded by Wall Street firms.

Toshiba’s QKD system offers multiplexing capability, which doubles network capacity by allowing the data channel and the quantum channel to be transmitted on one fiber. As a result, QKD transmissions have taken place over a 32km dark fiber across the Hudson River on one fiber, where two were previously required. This doubling of capacity provides twice the key material previously available as well as increasing availability of transmission while greatly reducing the number of fibers required for customers to access the Phio network.

Toshiba provided its Multiplexed Single Fiber QKD system operating in the O-Band. This system features high Raman noise tolerance, reducing photon scattering and is therefore suitable for combined commercial data and QKD traffic with both forward and directed traffic operating over a single fiber. This approach doubles the network capacity as only one fiber is required.

Alice was installed in a data center in New Jersey. Bob was installed in downtown Manhattan, New York in the data center at 60 Hudson Street. 1G encryptors were installed at each site. These encryptors provided encrypted data traffic launched at normal commercial optical powers into the same fiber as Toshiba QKD.

The figure below shows the performance over a 24 hour period of operation.

An average secure bit rate of 143 kbps was obtained with a quantum bit error rate of 3.31%. At the same time the QKD system provided quantum keys to the encryptors through the standard Toshiba key management application interface (API) and used by the encryptors to provide standard AES encryption of a live video conference between the two sites. The encryptors were configured to pull a new quantum key every minute to refresh the AES encryption.

The installation ran continuously for one month demonstrating the reliability of Toshiba QKD to operate commercially usable services with QKD and data multiplexed on a single fiber.