From the course: CompTIA Security+ (SY0-701) Cert Prep: 1 General Security Concepts
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PGP and GnuPG
From the course: CompTIA Security+ (SY0-701) Cert Prep: 1 General Security Concepts
PGP and GnuPG
Let's take a look at another asymmetric algorithm. In 1991, Phil Zimmermann released an algorithm that he called the Pretty Good Privacy or PGP algorithm. PGP is still widely used today, and the details are freely available for anyone to use through the OpenPGP standard. PGP uses public and private key pairs, but it performs encryption and decryption in a little more complex manner that combines both symmetric and asymmetric cryptography. Let's first take a look at the encryption process using PGP. The sender of a message has the original plaintext and then generates a random symmetric encryption key. Next, the sender encrypts the message using the random symmetric key and then encrypts the random key using the recipient's public key. The sender then transmits the encrypted message, which is a combination of the encrypted data and the encrypted random key. When the recipient receives that encrypted message, they perform the decryption process. First, they decrypt the encrypted random…