Contents
Asymmetric algorithms are better known as public/private-key. This encryption is best used between two parties who have no prior knowledge of each other but want to exchange data securely. Unlike symmetric algorithms, asymmetric algorithms use two different cryptographic keys to encrypt and decrypt plain text.
AES is a symmetric algorithm, so it does not have public and private keys – only a shared secret. In the simplest form: AES is a symetric algorithm, it uses the same key for encryption and decryption.So tat whoever has the key can read your message.
Is there a way to share a private key?
If the key being shared is not too long, and the thing it is protecting is not too secure, one easy way to share a key is to simply read it aloud over a relatively secure voice communication service such as whatsapp. As long as both parties can trust each other, such a method ensures that no 3rd copy of the key exists.
What happens when a shared key is used?
Now the both the Client and the Server know the shared key. At this point, the Client and the Server can both use the shared key for further communication. At some point the session is over and the shared key is disposed. Every session requires a new shared key. Thanks for contributing an answer to Information Security Stack Exchange!
Just place the public key in the remote machine’s ~/.ssh/authorized_keys file for passwordless entry. Don’t share the private key though. The keys are just for authentication. You can log on as many times as you wish with the same key, so long as you can log on with that private key once.
The most basic way to do this is for the server to first establish a session key with each user via a Diffie-Hellman or RSA key exchange in a manner similar to TLS, then use each user’s session key to encrypt the group key. In the event the group key needs to change, the server encrypts the new group key with each user’s session key.