Andrei's blog

MetaLearn: Public Key Encryption

Send a friend an open padlock, but keep the key.

Open locks can be shut closed without a key. Once your friend locks something with your padlock, only you will be able to open it. Put the padlock on a box, and you have a secure container you can send around.

Only digital encryption is magnitudes more secure1 than physical padlocks, which have stayed breakable for the last 160 years.

Send a friend your public key, but keep the private key.

You can encrypt messages using just the public key. Once your friend encrypts something with your public key, only you will be able to decrypt it.

It can't be that hard to explain public key encryption, but some reason media always overcomplicates public key encryption with confusing diagrams, animations, emoji, Alice, Eve, and Bob.

Note: Public key encryption is also called asymetric encryption (as opposed to symetric). RSA is a popular asymetric encryption algorithm. The 3 are often used interchangably.

Note: If you want to learn about technicalities of RSA and Cryptography, check Khan Academy Cryptography and Computerphile. (Shame on me for not knowing better resources)


Since I am at it, let's run through a bunch more information:

- very qualified cryptography expert

Footnotes

  1. Cryptographic strength is often presented as the amount of time needed to crack, but those estimates are algorithm and method specific. If you check forums or dig through research papers, you won't find clear answers. I can only say that the (most) developers use encryption algorithms that will take at least thousands of years to crack.