Asymmetric Encryption

• A public key infrastructure (PKI) is a system for the creation, storage, and distribution of digital certificates which are used to verify that a particular public key belongs to a certain entity.
• The PKI creates digital certificates which map public keys to entities, securely stores these certificates in a central repository and revokes them if needed.
• The public key infrastructure uses asymmetric encryption also known as public key, which is the most common method on the Internet for authenticating a message sender or encrypting a message.
• Traditional cryptography has usually involved the creation and sharing of a secret key for the encryption and decryption of messages. This symmetric or private key system has the significant flaw that if the key is discovered or intercepted by someone else, messages can easily be decrypted.
• For this reason, public key cryptography and the public key infrastructure is the preferred approach on the Internet.