PGP, Pretty Good Privacy

Description Glossary RFCs Publications Obsolete RFCs


Type:Encrypted file format.
MIME subtype:application/pgp-encrypted.
Working groups: openpgp, An Open Specification for Pretty Good Privacy.

RFC 1991:

PGP uses a combination of public-key and conventional encryption to provide security services for electronic mail messages and data files. These services include confidentiality and digital signature. PGP is widely used throughout the global computer community.

PGP was created by Philip Zimmermann and first released, in Version 1.0, in 1991. Subsequent versions have been designed and implemented by an all-volunteer collaborative effort under the design guidance of Philip Zimmermann. PGP and Pretty Good Privacy are trademarks of Philip Zimmermann.


GnuPG, GNU Privacy Guard.
This is an OpenPGP implementation that avoids all encumbered algorithms. Consequently, early versions of GnuPG did not include RSA public keys. GnuPG may or may not have support for IDEA or other encumbered algorithms depending on version.

A variant of PGP based on PGP 5.x.

PGP 2.6.x.
This version of PGP has many variants. It used only RSA, MD5, and IDEA for its cryptographic transforms.

PGP 5.x.
This version of PGP is formerly known as "PGP 3" in the community. It has new formats and corrects a number of problems in the PGP 2.6.x design.


[RFC 1991] PGP Message Exchange Formats.

[RFC 2015] MIME Security with Pretty Good Privacy (PGP).

[RFC 2440] OpenPGP Message Format.

[RFC 2726] PGP Authentication for RIPE Database Updates.

[RFC 3156] MIME Security with OpenPGP.

[RFC 5581] The Camellia Cipher in OpenPGP.


Obsolete RFCs:

Description Glossary RFCs Publications Obsolete RFCs