What is Public Key Encryption?
Public key encryption refers to a type of cypher architecture known as public key cryptography that utilizes two keys, or a key pair), to encrypt and decrypt data. One of the two keys is a public key, which anyone can use to encrypt a message for the owner of that key. The encrypted message is sent and the recipient uses his or her private key to decrypt it. This is the basis of public key encryption. Public key encryption is considered very secure because it does not require a secret shared key between the sender and receiver. Other encryption technologies that use a single shared key to both encrypt and decrypt data rely on both parties deciding on a key ahead of time without other parties finding out what that key is. However, the fact that it must be shared between both parties opens the door to third parties intercepting the key. This type of encryption technology is called symmetric encryption, while public key encryption is known as asymmetric encryption. A “key” is simply a sma
Public key encryption (PKE) uses a system of two keys: • a private key, which only you use (and of course protect with a well-chosen, carefully protected passphrase); and • a public key, which other people use. Public keys are often stored on public key servers. A document that is encrypted with one of these keys can be decrypted only with the other key in the pair. For example, let’s say that Alice wants to send a message to Bob using PGP (a popular public key encryption system). She encrypts the message with Bob’s public key and sends it using her favorite email program. Once the message is encrypted with Bob’s public key, only Bob can decrypt the message using his private key. Even major governments using supercomputers would have to work for a very long time to decrypt this message without the private key.
