Here, we discuss what is a PGP email, how to encrypt and decrypt a PGP email, and much more regarding PGP data encryption. PGP stands for Pretty Good Privacy and even though it has pretty good in its name, PGP encryption is much more than being just pretty good. Essentially, PGP data encryption is a security program you can use to send a PGP email or encrypt and decrypt email, as well as to authenticate your emails, send PGP messages, and PGP files through digital signatures.
PGP (Pretty Good Privacy) encryption was developed and designed back in 1991 by Paul Zimmermann. At the time, PGP encryption software was operated and owned by PGP Corporation. In 2010, the rights to PGP software were bought by Symantec. For hackers and cybercriminals, email is one of the prime hacking or attack methods as those who know how can easily fake messages using individuals’ identities and names.
PGP data encryption was designed and developed to solve these messaging security issues. Even though PGP encryption is used to encrypt files and text messages, it is mostly used as a way of enhancing the security and privacy of email by encrypting the content. Essentially, PGP emails are encrypted emails that nobody from the outside can access. In other words, PGP emails can only be accessed and viewed by the sender and the intended recipient.
PGP encryption software was the very first public cryptography tool available to everyone for free. Back in the day when it just appeared on the scene, it was primarily used to enable individuals to communicate safely and securely on computer servers. Later, PGP turned into the de facto email security and privacy standard and has been widely used not only by organizations but also by individuals who value their safety.
How PGP Email is Encrypted?
Just like many other data encryption technologies out there, PGP encryption relies on a combination of different hashing, data compression, and of course, powerful cryptography techniques. In other words, PGP emails are emails that have been compressed, hashed, and encrypted. PGP encryption is most similar to Kerberos, SSL (Secure Socket Layer), and SFTP (Secure File Transfer Protocol. Kerberos is responsible for authenticating data, Secure File Transfer Protocol secured data as it travels, and Secure Socket Layer secures and protects websites.
PGP emails arealways encrypted with the public key and in the PGP encryption system, every individual user has his or her unique public encryption key and this is key is shared among them. A PGP email also relies on a private key and private keys are never shared among users. Essentially, every user has a private key they keep secret and public encryption keys they share. An email is encrypted when a sender shares his or her public key. A PGP email is decrypted when the intended recipient accesses the email using his or her private key.
This means that a PGP email relies on both public-key and private-key cryptography and uses both asymmetric and symmetric data encryption technology to protect the content of emails as they travel from senders to recipients across networks. Every PGP email is protected and secured within three major steps:
PGP software or tool generated a one-time, random public key or encryption algorithm and this randomly generated algorithm protects PGP emails as it is always a completely random encryption session key nobody can guess
In the second step, the randomly generated session key or public key is encrypted using the PGP email’s recipient’s unique public key. Since session keys are also encrypted, a PGP email is protected during its transmission. The recipient of a PGP email shares his or her public key with individuals they want to get PGP-encrypted emails from.
The sender of a PGP email submits his or her randomly generated session key and the recipient of a PGP email uses his or her private encryption key to decrypt a PGP email or message.
PGP Email – Hashing, Data Compression, and Cryptography
Encrypting long emails or messages can take a while but with PGP encryption, the process is much faster and it relies on a faster encryption algorithm that includes data compression techniques. Since data techniques are used, encryption messages and emails save not only transmission time but also some space on your device. PGP encryption also fortifies cryptographic security. It is also worth mentioning that the public encryption key encrypts the shorter variant of the full emails and messages that have been PGP encrypted.
More specifically, the recipient of a PGP email gets both of them and uses his or her private key to access the shorter session key and finally decrypt the full PGP email or message version with all content included. In addition to data compression techniques, PGP encryption also relies on other efficient algorithms which create mathematical summaries also called a hash and these mathematical summaries are required to share digital signatures.
How to Send PGP Emails?
There are two major versions of PGP that rely on public-key cryptography including RSA (Rivest-Shamir-Adleman) and Diffie-Hellman. RSA relies on the IDEA (International Data Encryption Algorithm. Individuals create and share public keys and their public keys are needed in order to decode messages. RSA is extremely safe and almost unbreakable but encrypting messages using this encryption technology is very slow and it is not widely used for encrypting emails.
The Diffie-Hellman PGP version encrypts messages and emails with a short key with the CAST algorithm. It also easily creates hash codes thanks to the SHA-1 (Secure Hash Algorithm). To send a PGP email, you can use an excellent variety of PGP encryption software and tools out there and one of these is GNU Privacy Guard. You can also use Hushmail that is extremely safe and very easy to set up and get started. Other great options for sending your first PGP email include Claws Mail, EverDesk, eM Client, and The Bat that works on Windows devices.
If you are using a macOS device, you can send PGP emails with Apple Mail GPGTools, Canary Mail, Mutt, Enigmail, and Thunderbird. There are also PGP encryption tools for Android and iOS devices you can use to send your first PGP email such as iPGMail, PGPro, Safe Easy Privacy, R2Mail2, K-9 Mail OpenKeyChain, and FairEmail.