Quantum Unpredictability

ePrint Report: Quantum Unpredictability

Tomoyuki Morimae, Shogo Yamada, Takashi Yamakawa

Unpredictable functions (UPFs) play essential roles in classical cryptography, including message authentication codes (MACs) and digital signatures. In this paper, we introduce a quantum analog of UPFs, which we call unpredictable state generators (UPSGs). UPSGs are implied by pseudorandom function-like states generators (PRFSs), which are a quantum analog of pseudorandom functions (PRFs), and therefore UPSGs could exist even if one-way functions do not exist, similar to other recently introduced primitives …

authentication call cryptography digital digital signatures eprint report function functions macs message play quantum report roles signatures state states