tags: cryptography
Public-key cryptosystems and RSA mainly have 3 uses:
1. Key exchange
One of their main usages is probably key-exchange. For example when a device tries to contact web server it generates a key with a PRNG and encrypts it with the public key of the server, so only the server can decrypt it.
2. Data signing
Data signing is used to confirm the correct author of the message and also ensure that the original message was never tampered with. The following image describes the process:
3. Authentication
The same idea of data signing, but instead of a data message, a message holding user information or record is sent.
