Keeping data safe and secure is one of the greatest challenges posed by the rapid development of today’s information technology. More and more sensitive data is stored on remote computer servers, for example in the cloud, making secure access to this data a predominant concern. Securing the transmission and retrieval relies on encryption of information sent over public networks.

Quantum Key Distribution (QKD) is used to distribute the secret digital keys important for protecting highly sensitive data critical to many industries. In particular, it protects data in the finance, defence, utilities, and health sectors as well as the critical infrastructure that underpins our smart cities and smart energy grid.

The essence of QKD security relies on encoding each bit of the key upon a single photon (particle of light) transmitted, for example through an ordinary optical fiber. As any attempt to read the photons alters their encoding, this allows the secrecy of each key to be tested and guaranteed. Unlike other existing security solutions, QKD is secure from all future advances in mathematics and computing, including the data processing power of a quantum computer.

By adopting QKD, organisations can protect their communication infrastructure from today’s vast array of cyber-threats, as well as those of tomorrow. Already, hackers are using techniques such as harvest and decrypt, where data is scraped and stored today with the aim of decrypting it once they have the capability to do so through advances with supercomputers, the realisation of a quantum computer, or the discovery of new techniques for cryptanalysis. With QKD, any data which requires long-term protection is not only secure in today’s IT landscape, but also future-proofed to remain protected in the impending quantum age.

Robust levels of security are required in many sectors. For example, in healthcare, the technology has been applied to ensure the secure transmission of genome data in Japan, with personal medical information naturally some of the most sensitive available. Within the public sector QKD is used to provide government with secure communications, in the finance industry to protect banking network infrastructure and in aerospace and pharmaceuticals to protect high value long life Intellectual Property. Equally, in the age of IoT and smart cities, the necessity for a robust, tamper-proof and ultra-sensitive infrastructure is essential to ensure day-to-day life operates without disruption both now and in the future.