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Comment by echelon | Hacker News Reader

Google could put themselves and everyone else out of business if the algorithms that underpin our ability to do e-commerce and financial transactions can be defeated.

Goodbye not just to Bitcoin, but also Visa, Stripe, Amazon shopping, ...

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bitcoin proof of work is not as impacted by quantum computers - grover's algorithm provides a quadratic speedup for unstructured search - so SHA256 ends up with 128 bits of security for pre-image resistance. BTC can easily move to SHA512.

symmetric ciphers would have similar properties (AES, CHACHA20). Asymmetric encryption atm would use ECDH (which breaks) to generate a key for use with symmetric ciphers - Kyber provides a PQC KEM for this.

So, the situation isn't as bad. We're well positioned in cryptography to handle a PQC world.

Right? Does TLS1.3 have the underpinnings to use quantum-proof encryption algos?

https://en.wikipedia.org/wiki/Post-quantum_cryptography

https://www.microsoft.com/en-us/research/project/post-quantu...

https://www.forbes.com/councils/forbestechcouncil/2024/10/09...

It seems you can get TLS 1.3 (or atlest slighty modified 1.3) to be quantum secure, but it increases the handshake size by roughly 9x. Cloudflare unfortunately didn't mention much about the other downsides though.

https://blog.cloudflare.com/kemtls-post-quantum-tls-without-...

About one third of traffic with Cloudflare is already using post-quantum encryption. https://x.com/bwesterb/status/1866459174697050145

Signatures still have to be upgraded, but that's more difficult. We're working on it. http://blog.cloudflare.com/pq-2024/#migrating-the-internet-t...

Yes-ish. They're not enabled yet, but post-quantum signatures & KEMs are available in some experimental versions of TLS. None are yet standardized, but I'd expect a final version well before QCs can actually break practical signatures or key exchanges.

One third of all human traffic with Cloudflare is using a post-quantum KEM. I'd say that counts as enabled. We want that to be 100% of course. Chrome (and derivates) enabled PQ by default. https://radar.cloudflare.com/adoption-and-usage

It's currently believed that quantum computers cannot break all forms of public key cryptography. Lattice based cryptography is a proposed replacement to RSA that would let us keeping buying things online no problem.

Why is no one else talking about this? I came here to see a discussion about this and encryption.

Because this result is still very far from anything related to practical decryption.

And if they were, would they tell the world?

If they had a QC that could run Shor's algorithm to factor the number 1000, I'd guarantee you they'd tell the whole world. And it would still be a long, long time from there to having a QC that can factor 2048-bit numbers.

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