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kadobantoday at 4:30 AM1 replyview on HN

Is there? Like...kind of, but on the face of it I'd say about the same amount in both. If you look back at DES there's a _lot_ in common with modern ciphers, but like, RSA is still in use and that's old as shit.

I think you're right if your point is that we're more likely to see big breaks in asymmetric crypto, but it's kind of based on vibes to me, it's not really clear that it's provable in any way with anything like our current understanding.


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tptacektoday at 4:55 AM

AES doesn't reduce to a fundamental mathematical problem we're uncertain about, in the same way as discrete logs, factoring, the elliptic curve discrete log, or shortest vectors. It's a simpler idea, mathematically: rigorously understood linear operations to propagate key-driven changes quickly, disrupted by nonlinear operations to keep the cipher from being solvable with algebra, driven by a key schedule, and iterated enough times to destroy the signal that differential cryptography (and its analogs) would use to mount attacks.

It's just radically different levels of exposure to mathematical theory.

I'm fond of pointing out that JP Aumasson, who is (unlike me) an academic cryptographer of some repute, believes SHA2 will never be broken.

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