Internet governance bodies are about to move faster on a problem most users never see. John Crain, the chief technology officer of ICANN, told The Register at the organization’s annual meeting in Bali that work to prepare the domain name system for quantum computers is set to speed up. DNS quantum decryption attacks are not breaking anything today, but Crain said the timeline for getting ready has shortened, and that change is the news.
Crain said he is aware of predictions that commercially available quantum computers capable of easily deciphering encrypted information could arrive at the turn of the decade. Years ago, he said, he would have put DNS readiness ten years out. Now he puts it closer: “I don’t know if it’s three years or five, but it’s probably not ten.” He added: “We’re going to ramp up the speed of development.”
Nothing changes for ordinary users right now, and your browser will keep working the same way tomorrow. What changes is the planning inside the organizations running the internet’s addressing system, because replacing DNS security takes years, and the window for doing it calmly is getting smaller.
In Brief
- The warning: ICANN technology chief John Crain says work to make DNS quantum safe will accelerate, as capable machines are predicted around 2030.
- The risk: DNS quantum decryption attacks could one day threaten DNSSEC, which signs DNS answers so resolvers can trust them.
- The hard part: bigger quantum-safe keys strain DNS size limits, pushing traffic from single UDP messages toward multiple TCP packets.
- The timeline: predictable deployment is probably a few years away, and the UDP to TCP shift alone will take a few years.
- The bottom line: no quantum computer today can break DNSSEC, and no deployment date has been set.
How DNS Trust Works, in Plain Terms
DNS is the internet’s phone book. When you type petatech24.com, DNS turns that name into the numeric address your device connects to. DNSSEC, the Domain Name System Security Extensions, adds a signature to those answers. Your resolver checks the signature against a chain of trust, so it can tell a genuine answer from a forged one.
That signature system rests on conventional public-key cryptography, the family of mathematics protecting much of the web. A sufficiently powerful quantum computer running Shor’s algorithm could in theory defeat the RSA and elliptic-curve cryptography behind today’s signatures. That is the technical core of the worry: not a guessed password, but a forged signature sending users to a lookalike destination that appears legitimate. That signature is exactly what DNS quantum decryption attacks would target.
DNS Quantum Decryption Attacks: The Threat, Stated Carefully
Quantum stories are easy to overstate, so clarity matters. No quantum computer available today can break DNSSEC, and Crain did not claim otherwise. What he described is a planning shift driven by predictions, not a demonstrated break. That is why DNS quantum decryption attacks remain a planning problem, not an active incident. The machines that could challenge conventional encryption are still, in his framing, a prospect for around the turn of the decade, and predictions of that kind have moved before.
Security planners call a related worry harvest now, decrypt later: encrypted traffic recorded today could be decrypted years from now, once a capable machine exists. For DNSSEC, DNS quantum decryption attacks would work differently, but the risk is just as serious. DNS answers are not secret, they are trusted, so a future machine that can forge signatures would attack that trust directly. The fix must therefore be in place before the machines arrive, not after.
DNS Quantum Decryption Attacks and the Size Problem
One straightforward defense against DNS quantum decryption attacks is larger keys that even a quantum computer would struggle to crack. The problem, as Crain explained it, is that DNS was built for small, fast messages. Larger keys mean larger zones, packets and responses, and traffic that today travels in a single UDP message may instead need several TCP packets, changing how resolvers and servers handle every lookup.
That shift is not a settings tweak. Crain said ICANN, the Internet Engineering Task Force and other governance bodies have begun preliminary work against DNS quantum decryption attacks. Preparing the move from UDP to TCP will take a few years, he said, and the community is probably a few years away from deploying a quantum-safe DNS in a predictable manner. The work is measured in years on both sides: years to build it, and, on current predictions, only a few years before it is needed.
What Already Exists Outside DNS
DNS work does not start from zero. The US National Institute of Standards and Technology finalized its first three post-quantum cryptography standards in August 2024: FIPS 203 (ML-KEM key encapsulation), FIPS 204 (ML-DSA digital signatures) and FIPS 205 (SLH-DSA hash-based signatures). Those standards give the wider internet a tested toolbox for replacing vulnerable cryptography. Applying them to defend against DNS quantum decryption attacks, within DNSSEC and its strict size limits, is the part still in progress.
Further standards work continues. A FALCON-based draft standard, FN-DSA, is still in development, and NIST selected HQC in March 2025 as a code-based backup for key encapsulation. Draft NIST guidance has also proposed winding down RSA and elliptic-curve cryptography after 2030, with use disallowed after 2035. Those dates are proposals in draft guidance, not DNS deployment deadlines, but they illustrate why governance bodies feel pressure now in preparing for DNS quantum decryption attacks: migration of a global system cannot wait until the last year.
Also Decided in Bali
The quantum discussion was not the only governance work at ICANN 87. A reform of regional internet registry oversight, known as Internet Coordination Policy 2, reached recommended-draft status after public consultation. The current policy covers only forming a new regional registry; the update would cover the full lifecycle, including recognition, audit, emergency continuity operations and derecognition, giving ICANN a major role as independent overseer. Jia-Rong Low, chair of the Number Resource Organization, hopes a final document will be ready for review by the end of 2026. Separately, ICANN principal security scientist Siôn Lloyd reported that Category 1 generic top-level domains, such as .bank, .doctor, .university and .sucks, face a 45 percent higher chance of abuse than other domains, though they are less likely to carry high abuse volumes.
Confirmed, Reported, Unknown
Quick Answers
Can a quantum computer break DNS today?
No. No publicly known machine can break DNSSEC through DNS quantum decryption attacks, and nothing in Crain’s remarks suggests otherwise. The work is preparation for machines predicted around the turn of the decade.
Will my browsing or my website break?
No change is coming for users in the near term. The engineering work sits with governance bodies and standards groups, and any future transition would be staged so existing resolvers keep working.
What should domain owners and operators do now?
Nothing urgent is required to defend against DNS quantum decryption attacks, since no quantum-safe DNSSEC standard has been deployed. The sensible step is to watch IETF and ICANN drafts and inventory conventional cryptography use, since any future migration will need that inventory.
When will quantum-safe DNS arrive?
No date has been set for defenses against DNS quantum decryption attacks. Crain said predictable deployment is probably a few years away, and preparing the move from UDP to TCP alone will take a few years. Any firmer date would be speculation.
The Takeaway
The story here is a change of pace, not a crisis. A decade of runway has become three to five years in the judgment of ICANN’s chief technology officer, and the organizations that run DNS are responding by speeding up work that is still preliminary. The size problem is real, the standards toolbox exists in general form, and the deployment date does not. Readers should take two things from this: DNS quantum decryption attacks are a genuine long-term threat to the trust layer of the internet, and the people responsible for that layer are now treating the clock as shorter than they did. That warning matters most while it still arrives early, with time to act.
Sources: The Register, Work to protect DNS from quantum decryption attacks is speeding up (October 26, 2026), reporting from ICANN 87 in Bali; NIST standards FIPS 203, 204 and 205, finalized August 2024. PetaTech24 tested nothing here and confirms no deployment date, algorithm choice or price.
