A Quantum Leap in Cybersecurity: Novel Paradigms for Safe Digital Communication

The popularity of quantum computing poses a risk to the broad usage of public key cryptography since Shor algorithm can shrink both RSA and elliptic curve systems once large enough fault-tolerant quantum computers are available. This paper briefly describes the security implication on current infrastructures such as public key protocols and blockchain transactions, why the concept of harvest now, decrypt later poses instant long term confidentiality risk. We also survey post quantum alternatives such as lattice based cryptography (encompassing NTRU) and code based schemes, as well as Quantum Key Distribution (QKD) as a supplementary tool to establish high assurance keys. Deployment constraints are emphasized as including hardware overheads, complexity of migration and the QKD distance/rate constraints. The article offers a security conscious, implementation conscious analysis relating quantum dangers, migrate to post-quantum needs (crypto agility and hybrid deployment) and practical QKD suppliers that assists to incorporate near term transition planning.