Post Quantum Cryptography: Standardization Status and Blockchain Impact

Khadijeh Bagheri is a Postdoctoral Research Fellow in the School of Engineering at the University of British Columbia (UBC), Okanagan Campus. Her research focuses on cryptography and blockchain security, with particular em-phasis on post‑quantum cryptography, quantum‑resistant blockchains, and infor-mation‑theoretic security. Dr. Bagheri received her Ph.D. in Mathematics and Computer Science from Amirkabir University of Technology (Tehran Polytechnic), where her doctoral research focused on lattice‑based and code‑based cryptography. She previously held research positions at Sharif University of Technology and the Institute for Research in Fundamental Sciences (IPM) in Tehran, contributing to both theo-retical and applied cryptographic research. Her work spans post‑quantum digital signatures, lattice‑ and code‑based crypto-graphic constructions, secure communication systems, and blockchain protocol design. Her current research at UBC explores practical approaches to deploying quantum‑resilient cryptographic solutions in real‑world blockchain systems.

Abstract: The emergence of quantum computing challenges the computational assumptions underlying widely deployed public key cryptography, including factoring and discrete logarithm-based schemes that are fundamental to secure communication and blockchain systems. Although large-scale, fault-tolerant quantum computers are not yet available, the threat is already relevant through “harvest-now, de- crypt-later” attacks, particularly for systems with long-lived data, publicly visible state, and irreversible commitments, as is common in blockchains. This talk presents a technical overview of post-quantum cryptography (PQC), focusing on the progression from hardness assumptions to stand- ardized cryptographic primitives and their early deployment. We review the current status of the PQC standardization process led by the National Institute of Standards and Technology (NIST), including recently standardized algorithms for key establishment and digital signatures, and discuss their readiness for practical adoption. A comprehensive analysis of the quantum threat landscape for blockchain systems is provided in our survey paper: Navigating the Quantum Computing Threat Landscape for Blockchains. We then examine the implications of PQC for blockchain protocol design. Quantum adversaries affect not only transaction authentication through digital signatures, but also address reuse, long-term key exposure, and cryptographic assumptions in consensus mechanisms. The discussion considers how post quantum primitives may be incorporated into existing blockchain architectures, and how these choices interact with system constraints such as on chain efficiency, bandwidth, and scalability. The talk aims to connect cryptographic theory with blockchain systems research by highlighting open challenges in designing quantum-resilient decentralized protocols.