3 ms·

Yet, if you call a public key/private key a lock/key respectively, then a lot more people would immediately get the concept. "You send him a copy of your lock

Yet, if you call a public key/private key a lock/key respectively, then a lot more people would immediately get the concept. "You send him a copy of your lock which he uses to lock a package and return it to you. Then only your key can open it!" You immediately fix the problem of people sending their key, because people know keys are important and shouldn't be handed out to just anyone. The PKI people are brilliant. Their communication skills, not so much.

aikinai 12y ago
I've always wondered why we couldn't just call public keys locks. That would avoid so much confusion for first-time users.
- peeters 12y ago
  Probably because the analogy breaks down so fast. "And to prove he sent the package, he locks it with his key and then you use your copy of his lock to open it so that you know it's from him!" It's a useful analogy for one specific use of public/private keys. But it doesn't capture the full spirit, which may lead to more confusion than just using no analogy.
  - teraflop 12y ago
    It's not true in general that public-key encryption and digital signatures are inverse operations. (RSA has that property, but there are plenty of other algorithms that don't work that way.) If you're writing for a lay audience that doesn't care about things like modular arithmetic, there's no reason to conflate the two operations. Just say encryption is like keys and locks, and signing is like... well... a signature.
    - tedunangst 12y ago
      So this public key is like a lock and that public key is not like a lock. Got it.
- slavik81 12y ago
  After reading 'Why King George III Can Encrypt'[1] I really started hoping that something came of it. The metaphors they used seemed much more straightforward. [1] https://freedom-to-tinker.com/blog/randomwalker/why-king-george-iii-can-encrypt/ https://freedom-to-tinker.com/blog/randomwalker/why-king-geo...

aikinai 12y ago

I've always wondered why we couldn't just call public keys locks. That would avoid so much confusion for first-time users.

peeters 12y ago
Probably because the analogy breaks down so fast. "And to prove he sent the package, he locks it with his key and then you use your copy of his lock to open it so that you know it's from him!" It's a useful analogy for one specific use of public/private keys. But it doesn't capture the full spirit, which may lead to more confusion than just using no analogy.
- teraflop 12y ago
  It's not true in general that public-key encryption and digital signatures are inverse operations. (RSA has that property, but there are plenty of other algorithms that don't work that way.) If you're writing for a lay audience that doesn't care about things like modular arithmetic, there's no reason to conflate the two operations. Just say encryption is like keys and locks, and signing is like... well... a signature.
  - tedunangst 12y ago
    So this public key is like a lock and that public key is not like a lock. Got it.
slavik81 12y ago
After reading 'Why King George III Can Encrypt'[1] I really started hoping that something came of it. The metaphors they used seemed much more straightforward. [1] https://freedom-to-tinker.com/blog/randomwalker/why-king-george-iii-can-encrypt/ https://freedom-to-tinker.com/blog/randomwalker/why-king-geo...