Hoskinson Says Post-Quantum Crypto Could Slow Blockchains

• Post-quantum cryptography tools exist, but early adoption could sharply reduce blockchain performance.
• Hoskinson says timing and hardware readiness matter more than cryptographic availability.
• Unclear quantum timelines force networks to balance future security against current efficiency.

Cardano founder Charles Hoskinson has cautioned that building blockchain networks for post-quantum cryptography involves clear performance trade-offs, arguing that the key question for developers is not whether the tools exist, but when adopting them becomes practical.

In comments on the emerging debate over quantum-resistant upgrades, Hoskinson said cryptographic standards designed to withstand future quantum attacks are already available. However, he stressed that deploying them prematurely could reduce network efficiency if supporting hardware is not yet in place.

Timing, Not Tools, Frames the Post-Quantum Debate

Hoskinson pointed to post-quantum cryptography standards released in 2024 by the National Institute of Standards and Technology, noting that the technology itself is no longer theoretical. Instead, he said the concern lies in the operational costs of implementing live blockchain systems.

According to Hoskinson, post-quantum schemes usually result in much larger proofs and slower processing. He said this could translate into lower throughput for blockchains that adopt the standards too early, effectively reducing transaction capacity by an order of magnitude. In his view, this results in readiness among miners and validators, a critical factor in determining when such upgrades should occur.

Uncertainty Over the Quantum Threat Timeline

While researchers generally agree that sufficiently advanced quantum computers could eventually compromise today’s cryptographic systems, there is no consensus on when that capability will materialize. Estimates range from a few years to well over a decade, leaving protocol designers to balance long-term security against near-term performance.

Hoskinson stated that assessments of quantum progress should rely less on corporate announcements and more on independent benchmarks. He highlighted the Defense Advanced Research Projects Agency Quantum Benchmarking Initiative, which evaluates whether competing quantum computing approaches can deliver practical results. He described the program as an objective reference point for measuring when quantum systems may pose a real threat.

Competing Cryptographic Paths Across Networks

Like most major blockchain networks, including Bitcoin, Ethereum, and Solana, Cardano currently relies on elliptic-curve cryptography. This method could theoretically be broken by Shor’s algorithm if large-scale quantum computers become viable.

Hoskinson said the industry already understands how to mitigate that vulnerability, but faces a strategic choice between two primary cryptographic approaches. One relies on hash-based systems, which he said Ethereum is pursuing, while the other uses lattice-based cryptography, which Cardano is developing.

Overall, Hoskinson’s remarks framed post-quantum security as a question of sequencing, with performance costs and infrastructure readiness shaping when blockchains should transition to new cryptographic standards.

Related: How Cardano’s PQC Wallet Prepares Blockchain for the Quantum Computing Era