Asymmetric encryption, also known as public-key cryptography, involves two keys: a public key, which can be shared widely, and a private key, which is kept confidential. The public key is used for encryption, and the private key is used for decryption. This method is scalable because it allows for secure communication over an open network without the need for the parties to share secret keys in advance. While asymmetric encryption is generally slower than symmetric encryption due to the complex mathematical computations involved, it provides a high level of security and is essential for tasks such as digital signatures and establishing secure connections over the internet.