HSBC said it intends to use a quantum-secured metro network to evaluate secure transmission of data across standard fiber-optic cables between its global headquarters at Canary Wharf in London's Docklands, and a datacenter 62km (38 miles) away.

The bank will use the network for carrying financial transactions and secure video communications, as well as for one-time-pad encryption, and will be testing the network's use in edge computing by connecting an AWS Snowball Edge device.

The network was announced last year by BT and uses quantum key distribution (QKD) over standard 10Gbps fiber-optic connections to secure end-to-end transmissions. The QKD hardware and the key management systems are provided by Toshiba, and the whole system is a three-year commercial trial to gauge the viability of a quantum-secured metro network.

BT has already had accounting firm EY testing out the network to link two of its sites in London, one at Canary Wharf and one other near London Bridge.

QKD is a method of securely distributing encryption keys by encoding the information into the quantum states of individual photons. Once this is accomplished, information can be exchanged normally using the keys to encrypt transmissions. The tricky part is building the network so the QKD can use the same optical fibers as the data traffic rather than needing dedicated lines.

HSBC said its exploration of quantum-secure communications is intended to glean crucial evidence into the effectiveness of the technology and drive the development of future applications for financial security.