I came across an article about one-time pads on Bruce Schneier's newsletter. He says that, although it's the only provably secure crypto system we know of, it has no future. He argues that one-time pads turn a message security problem into a just-as-difficult key distribution problem.
This is correct, assuming we don't want to be occupied with running around with briefcases, handcuffed to our wrist. And indeed, there is no need to go through all that trouble. We now have asymmetric public key algorithms, based on factoring large primes. They securely protect the message key of the symmetric encryption, used to encrypt the data. But there's a problem.
Although it has taken lots of time, defactoring (limited) primes is possible and already done. Imagine what would happen when someone finds a mathematical shortcut for the factoring problem, or a hardware solution, speeding up the process, as expected from quantum computers? Imagine a world where asymmetric encryption no longer resists against maths, or any symmetric cipher is brute forced within minutes?
One-time pads would be the only solution, although a very expensive one due to the key distribution problems. It's a bit like using Morse code on radio. Several armed forces abandoned Morse. Yes, it's stone-age technology, and one can say it's ridicules in these Megabit-rate days of data communication. And what do we see now... we start teaching Morse again to Army signal operators. When things go bad, Morse is the only system getting across, all others failing. So, I think we should never throw away those solid systems like one-time pads too fast.
This is correct, assuming we don't want to be occupied with running around with briefcases, handcuffed to our wrist. And indeed, there is no need to go through all that trouble. We now have asymmetric public key algorithms, based on factoring large primes. They securely protect the message key of the symmetric encryption, used to encrypt the data. But there's a problem.
Although it has taken lots of time, defactoring (limited) primes is possible and already done. Imagine what would happen when someone finds a mathematical shortcut for the factoring problem, or a hardware solution, speeding up the process, as expected from quantum computers? Imagine a world where asymmetric encryption no longer resists against maths, or any symmetric cipher is brute forced within minutes?
One-time pads would be the only solution, although a very expensive one due to the key distribution problems. It's a bit like using Morse code on radio. Several armed forces abandoned Morse. Yes, it's stone-age technology, and one can say it's ridicules in these Megabit-rate days of data communication. And what do we see now... we start teaching Morse again to Army signal operators. When things go bad, Morse is the only system getting across, all others failing. So, I think we should never throw away those solid systems like one-time pads too fast.
One-time pad gained a reputation as a simple yet solid encryption system with an absolute security which is unmatched by today's modern crypto algorithms. Whatever technological progress may come in the future, one-time pad encryption is, and will remain, the only truly unbreakable system that provides real long-term message secrecy. Here's more detailed information about one-time pad.
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