Preparing for Q-Day
Episode
46 min
Read time
2 min
Topics
Software Development, Product & Tech Trends, Crypto & Web3
AI-Generated Summary
Key Takeaways
- ✓Harvest-now-decrypt-later exposure: Over 65% of Cloudflare clients already use post-quantum key exchange (ML-KEM), protecting against adversaries recording encrypted TLS sessions today for future quantum decryption. Engineers running modern browsers get this protection automatically, but server-side certificate automation must be implemented now to cover the remaining gap before Q-Day arrives.
- ✓Post-quantum certificate deployment timeline: Chrome will begin accepting post-quantum certificate authorities in Q1 2027. Servers will need two simultaneous certificates — one classical RSA/ECC and one post-quantum — to maintain backward compatibility. Engineers should audit whether their application servers currently support multiple certificate slots, since many assume a single slot only.
- ✓Signature size performance impact: ML-DSA-44 post-quantum signatures measure 2.5 kilobytes versus 64 bytes for elliptic curve signatures. TLS handshakes typically send six signatures, adding roughly 15 kilobytes per connection. Since approximately half of QUIC connections transfer under 8 kilobytes total, engineers must audit latency-sensitive or bandwidth-constrained endpoints for degradation before enabling post-quantum authentication by default.
- ✓Quantum timeline compression: Required physical qubits to break RSA-2048 dropped from 200 million to roughly 1 million on superconducting hardware. A separate result using neutral-atom reconfigurable architectures shows P-256 elliptic curve keys crackable with only 10,000–20,000 physical qubits in approximately one month, making a 2030 cryptographically relevant quantum computer plausible rather than theoretical.
- ✓Migration prioritization framework: Rather than bottom-up key inventories, engineers should conduct top-down business continuity analysis — assuming a quantum computer exists today and mapping actual operational impact per system. Hard cases to surface immediately include JWT tokens in URLs, chunky HTTP headers, hardware-bound cryptography, bespoke protocols like WireGuard, and vendor dependencies with no clear upgrade roadmap.
What It Covers
Cloudflare cryptography engineer Bas Vesterbahn joins host Kevin Ball to explain how quantum computers threaten public key cryptography via Shor's algorithm, why Q-Day timelines have compressed dramatically toward 2029, and what concrete steps software engineers must take now to migrate systems to post-quantum standards.
Key Questions Answered
- •Harvest-now-decrypt-later exposure: Over 65% of Cloudflare clients already use post-quantum key exchange (ML-KEM), protecting against adversaries recording encrypted TLS sessions today for future quantum decryption. Engineers running modern browsers get this protection automatically, but server-side certificate automation must be implemented now to cover the remaining gap before Q-Day arrives.
- •Post-quantum certificate deployment timeline: Chrome will begin accepting post-quantum certificate authorities in Q1 2027. Servers will need two simultaneous certificates — one classical RSA/ECC and one post-quantum — to maintain backward compatibility. Engineers should audit whether their application servers currently support multiple certificate slots, since many assume a single slot only.
- •Signature size performance impact: ML-DSA-44 post-quantum signatures measure 2.5 kilobytes versus 64 bytes for elliptic curve signatures. TLS handshakes typically send six signatures, adding roughly 15 kilobytes per connection. Since approximately half of QUIC connections transfer under 8 kilobytes total, engineers must audit latency-sensitive or bandwidth-constrained endpoints for degradation before enabling post-quantum authentication by default.
- •Quantum timeline compression: Required physical qubits to break RSA-2048 dropped from 200 million to roughly 1 million on superconducting hardware. A separate result using neutral-atom reconfigurable architectures shows P-256 elliptic curve keys crackable with only 10,000–20,000 physical qubits in approximately one month, making a 2030 cryptographically relevant quantum computer plausible rather than theoretical.
- •Migration prioritization framework: Rather than bottom-up key inventories, engineers should conduct top-down business continuity analysis — assuming a quantum computer exists today and mapping actual operational impact per system. Hard cases to surface immediately include JWT tokens in URLs, chunky HTTP headers, hardware-bound cryptography, bespoke protocols like WireGuard, and vendor dependencies with no clear upgrade roadmap.
Notable Moment
Vesterbahn reveals that Google published a zero-knowledge proof confirming they discovered a more efficient elliptic curve attack algorithm — without releasing the algorithm itself. This signals the cryptographic community that the threat is real and accelerating, while deliberately withholding details that adversaries could exploit.
Episode Transcript
Most of the cryptography securing the Internet today rests on mathematical problems that classical computers cannot solve in any reasonable time frame. That assumption is now being tested. Recent advances in quantum computing have dramatically compressed timelines, and many in the industry have set a target of full post quantum security by 2029, meaning a complete migration to algorithms designed to remain secure against quantum attacks. Bas Vesterbahn is a cryptography engineer at Cloudflare, where he leads the company's efforts to migrate to post quantum cryptography. In this episode, Bas joins Kevin Ball to discuss how quantum computers threaten public key cryptography, what post quantum algorithms actually are and how they work, the timeline shifts that have made quantum readiness feel so urgent, and what software engineers need to do now to prepare their systems. Kevin Ball or Kay Ball is the vice president of engineering at Mento and an independent coach for engineers and engineering leaders. He cofounded and served as CTO for two companies, founded the San Diego JavaScript meetup, and organizes the AI in action discussion group through Latent Space. Check out the show notes to follow Keball on Twitter or LinkedIn, or visit his website, keball.llc. Bas, welcome to the show. Hey, Kevin. Nice to be here. Yeah. I'm excited for this topic. This is one that has been suddenly raising my awareness, but I don't know enough about it. So I'm really eager to pick your brain. But let's start with a little bit about you. Can you kind of give us a little bit of your background and how you got to where you are today? It's quite a windy road. I I always liked security and cryptography at high school. Decided to go study physics and mathematics because I thought that would be more challenging. Didn't end up being very good at the physics, so I stuck with the mathematics, at least. I mean, the physicists, they they know how to bend the rules. Right? And I don't know how to do that. Did mathematics, then I did a PhD, going back to physics a little bit in the mathematical foundations of quantum computing, and the physics kept pulling me. But, actually, I did that at the security group of my university. So when I would be avoiding working on my actual thesis, I would be spending time with the cryptographers around there. So that's the there's people doing post quantum cryptography there and and this aren't symmetric cryptography. So I kinda learned by osmosis just during the the coffee breaks and stuff. After that, when I did went for a post doc to London. London is expensive, so I thought maybe I can find an internship or something. Already some crypto engineering. So I via via, I ended up with an internship at Cloudflare. I enjoyed that so much doing crypto engineering there that after COVID, I got invited to join full time in The Netherlands back, and I've been there ever …
Get the full transcript (8,619 words) + summary by email — free
One-time email with the complete transcript and AI summary of this episode. No account needed.
One email, no spam. We’ll also show you what SignalCast does.
You just read a 3-minute summary of a 43-minute episode.
Get Software Engineering Daily summarized like this every Monday — plus up to 2 more podcasts, free.
Pick Your Podcasts — FreeKeep Reading
More from Software Engineering Daily
A Rust Framework to Simplify Distributed Systems
Sep 10 · 50 min
Pod Save America
What Will Democratic Governance Look Like? + Lina Khan (Crooked Con)
Nov 23
More from Software Engineering Daily
SED News: The NVIDIA-Hugging Face Deal, China’s Proxy Economy, the Open Weight Surge
Sep 8 · 52 min
The Vergecast
How to buy a laptop when everything’s expensive
Aug 27
Books, tools, and gear mentioned in this episode
SignalCast may earn commission on purchases via these links.
Tools
“Over 65% of Cloudflare clients already use post-quantum key exchange (ML-KEM), protecting against adversaries recording encrypted TLS sessions today for future quantum decryption.”
“ML-DSA-44 post-quantum signatures measure 2.5 kilobytes versus 64 bytes for elliptic curve signatures.”
“Hard cases to surface immediately include JWT tokens in URLs, chunky HTTP headers, hardware-bound cryptography, bespoke protocols like WireGuard, and vendor dependencies with no clear upgrade roadmap.”
More from Software Engineering Daily
We summarize every new episode. Want them in your inbox?
A Rust Framework to Simplify Distributed Systems
SED News: The NVIDIA-Hugging Face Deal, China’s Proxy Economy, the Open Weight Surge
Moving Beyond RAG with Precomputed Context
The Death of Online Anonymity
TypeScript 7 and What Comes Next
Similar Episodes
Related episodes from other podcasts
Pod Save America
Nov 23
What Will Democratic Governance Look Like? + Lina Khan (Crooked Con)
The Vergecast
Aug 27
How to buy a laptop when everything’s expensive
The Daily (NYT)
Aug 23
Think Baseball Is Boring? The Savannah Bananas Are Here to Fix That.
The Joe Rogan Experience
Aug 20
#2543 - MrBallen
The AI Breakdown
Aug 18
The AI Engineering Skills Map for Knowledge Workers
Explore Related Topics
This podcast is featured in Best Cybersecurity Podcasts (2026) — ranked and reviewed with AI summaries.
Read this week's Software Engineering Podcast Insights — cross-podcast analysis updated weekly.
You're clearly into Software Engineering Daily.
Every Monday, we deliver AI summaries of the latest episodes from Software Engineering Daily and 192+ other podcasts. Free for one show.
Start My Monday DigestNo credit card · Unsubscribe anytime