Simpósio Brasileiro de Cibersegurança (SBSeg)
Non-Interactive Quantum Zero-Knowledge: Scope, Limits, and the Cost of Shared Entanglement in Authentication Protocols
Éricles Antônio Aquiles Barbosa Lima
Abstract
Non-interactive quantum statistical zero-knowledge (NIQSZK), introduced by Kobayashi in 2002 via shared EPR pairs replacing a classical common reference string, is often invoked as a general tool for quantum-native authentication, but the term spans results of very different scope. We give an account of what Kobayashi’s model actually establishes – non-interactive proofs for one promise problem, Quantum State Closeness to Identity, and, by reduction, Graph Non-Automorphism – and contrast it with the independent, more recent line achieving non-interactive zero-knowledge arguments for all of QMA from quantum-hardness of Learning With Errors (LWE). Using a Software-Defined Quantum Network (SDQN) control-plane authentication case study, we compare the realistically available proof systems along a resource-cost model grounded in published entanglement-distribution benchmarks and lattice-parameter estimation, and argue classical post-quantum NIZK dominates unless the credential itself is an inherently quantum object.