Quantum security at all distance scales

Current public key cryptographic systems are based on the presumed difficulty of certain mathematical operations, which may become vulnerable to attack in the future, especially in light of advances in quantum computing. Though specific timescales in relation to the latter are difficult to establish, for certain classes of data, the threat is already imminent, given that currently encrypted communications can be stored now and “broken” in the future, when the tools exist. Clearly new approaches to security are required.

One approach is to utilise shared keys – for encryption and decryption – and cryptographic techniques immune to such future attacks. Then the security is determined by the security of the key distribution mechanism. This is where the quantum technology comes in – it provides a secure method of quantum key distribution (QKD).

The Hub is exploring the development of advanced QKD technologies across many platforms – on miniaturised chips for integration with existing electronics; over conventional optical fibre for incorporation of these new technologies into existing telecommunications infrastructure; and over free space to enable both widespread use of secure handheld devices at short distances, and the establishment of secure networks at a global scale through satellites and optical ground stations.