[nhaehnle]

Please point to a proof of the security of symmetric crypto if you can. Last I checked, such a proof would have still been considered an incredible breakthrough.

All that people are doing is to show that k rounds of cypher C can be broken, where actual implementations use K > k rounds, and then arguing that nobody has been able to break more despite a lot of effort, cypher C is probably secure in practice. That is good evidence, but not a proof.

[Groxx]

One-time-use random data XOR your data = provably secure symmetric crypto, afaik. I could try to hunt down a proof of that one. Impractical, sure, but provable.

Also afaik, others haven't been proven / can only be proven to have certain qualities, and leave gaps which have massive real-world implication. So yeah, I'm curious for other proofs too.

[duaneb]

One time pads are currently the only provable "unbreakable" encryption. The proof is trivial.