Cyber Risk Mitigation in the Era of Quantum Computing*

Cryptographically relevant quantum computers (CRQC) can break standard encryption schemes such as RSA and forge digital identity and digital signatures, thus creating chaos in our financial transactions and threatening the security of our critical infrastructure. Large IT corporations such as Google and IBM are racing to build CRQC, possibly by 2030. Indeed, the “harvest now and decrypt later” attack may threaten our communication security even today.

In this talk, I will review the quantum threat to cyber-security. Moreover, I will briefly review the three classes of methods to counter this quantum threat including quantum-resistant conventional cryptography (often called post-quantum cryptography (PQC)), quantum key distribution (QKD), and pre-shared keys (PSK). I argue that they form the three pillars needed to address this immense security challenge.

PQC is currently being standardized by NIST, but it can never be proven to be fundamentally secure. The immense progress in the key rate and security of QKD over the last few decades will be reviewed together with the unappreciated importance of PSK solutions for securing our long-term secrets.