How does message encryption work?

Question

PHP

Hello! Interested in such a question, how is the encryption of messages in chats?

When adding a message to the database, is it encrypted by type like a password and then displayed with decryption? Right?

And please tell me how best to encrypt and decrypt messages?

Answer 1

Depending on what specific chats, in 99.9% of chats - no way. The only encryption that is present is by means of SSL between the client and the server.

Answer 2

To encrypt any data, you can use a public key system. A good implementation is RSA. https://ru.wikipedia.org/wiki/RSA

Answer 3

And please tell me how best to encrypt and decrypt messages?

1. By replacing characters with groups of characters. Decryption - in reverse order. Recursion is allowed.
2. Exchange of a replacement table via an N-character pin-code (according to a previously known algorithm, the algorithm itself is never transmitted over the network!) - based on RSA or in clear text (plain text).
3. Iteration of the substitution table is strictly required!
This is the easiest way.