Asymmetric encryption uses different keys to encrypt and decrypt a message. Typically there are two keys, a public and a private key. As the name suggests, the public key is publicly known, while the private key is a secret. ![[asymmetric_encryption.excalidraw.light.svg]] The message is encrypted using the recipient's public key. Let's say that Alice wants to send a message to Bob. She encrypts the message with Bobs public key which is publicly available. The recipient, Bob, can decrypt it using their private key which is only known to him. Decryption using the Bob's public key is not possible. One famous asymmetric key algorithm is the [[Rivest-Shamir-Adleman Algorithm|RSA algorithm]]. This algorithm in particular uses a [[Trapdoor function|trapdoor function]] which can be broken with [[Quantum Computer|quantum computers]] with the [[Shor Algorithm|Shor algorithm]]. >[!read]- Further Reading >[[Rivest-Shamir-Adleman Algorithm|RSA]] >[[Symmetric Encryption]] >[[Encryption Key]] >[[Shor Algorithm]] >[!ref]- References > - R. L. Rivest, A. Shamir, and L. Adleman, A method for obtaining digital signatures and public-key cryptosystems, Commun. ACM **21**, 120 (1978).