What Is Pretty Good Privacy?
PGP or Pretty Good Privacy is a program which is used to encrypt and decrypt emails on the internet along with authenticating messages with digital signs and encrypted stored files. While it was initially available as free-ware, it is now only available as a commercial version and isn’t very expensive. It was even used before as the most widely used program which ensured privacy to individuals and was also used by a number of companies. It was developed in 1991 by Philip R. Zimmermann and has now become a de-facto standard for security in emails.
How this program works is that it makes use of a variation of the public key system in which every user has an encryption key which is known publicly along with a private key which is only known to that specific user. Messages are encrypted using the public key when being sent to someone. Once they receive it, they will use their private key to decrypt the message you have sent. Since the process of encrypting an entire message can take time, the program offers a way to encrypt in a faster way which is through an algorithm. This encrypts the message and then makes use of the public key to encrypt the shorter key which was used in encrypting the whole message. Both messages as well as the short key are then sent to the receiver who uses his own private key to decrypt the short key and then decrypts the entire message.
There are 2 public key versions available which is the RSA (Rivest Shamir Adleman) and the Diffie-Hellman. The former requires PGP to pay a license fee for it and it uses an IDEA algorithm to generate a short key for the whole message as well as the RSA to encrypt the short key. The latter makes use of the CAST algorithm for the short key to encrypt the message and then makes use of the Diffie-Hellman algorithm for encrypting to the shorter key.
An efficient algorithm is used by PGP when digital signatures are sent and it generates a hash from the users name and other information. This code is also encrypted on the private key of the sender. The receiver of the message then makes use of the public key of the sender to decrypt the hash code. Once it matches, the receiver can be sure of where the message has arrived from.
To make use of the PGP, you can either download it or buy it and then install it onto your computer. It contains a user interface which works with a customary email program. You are also required to register the public key which the program gives you with the PGP public key server to enable you to exchange messages and to allow others to find your public key.
The freeware is available for older versions of operating systems such as Mac, Windows, Unix and DOS. In 2010 however Symantec Corp acquired the PGP Corp which held the rights of the PGP code and stopped offering this technology through the freeware version. While the freeware version of it was stopped, there are other non-proprietary versions of it available.
The program can be used in authenticating any digital certificates as well as encrypt and decrypt emails, files, texts, whole disk partitions and directories. If the PGP technology is used for drives and files instead of for messages, the Symantec products make it possible for users to decrypt the then re-encrypt data through a single sign-on.
The US government originally restricted that the technology be exported and even initiated the launch of a criminal investigation against Zimmermann for having put the technology out into the public domain however the investigation was dropped later. Today, PGP encrypted emails can also be exchanged with those living outside the United States as long as the correct version is being used on both ends.
There are a number of versions of the program which are in use currently. Add-ons can also be bought which allow backwards compatibility of the newer versions of the RSA with the older versions. The Diffie-Hellman and RSA versions however do not work with each other as they make use of different algorithms.