Pretty Good Privacy

tool, cryptography (PGP) A high security RSA public-keyencryption application for MS-DOS, Unix, VAX/VMS, and

other computers. It was written by Philip R. Zimmermann

[email protected] of Phil's Pretty Good(tm) Software and later

augmented by a cast of thousands, especially including Hal

Finney, Branko Lankester, and Peter Gutmann.

PGP was distributed as "guerrilla freeware". The authors

don't mind if it is distributed widely, just don't ask Philip

Zimmermann to send you a copy. PGP uses a public-keyencryption algorithm claimed by US patent #4,405,829. The

exclusive rights to this patent are held by a California

company called Public Key Partners, and you may be

infringing this patent if you use PGP in the USA. This is

explained in the PGP User's Guide, Volume II.

PGP allows people to exchange files or messages with privacy

and authentication. Privacy and authentication are provided

without managing the keys associated with conventional

cryptographic software. No secure channels are needed to

exchange keys between users, which makes PGP much easier to

use. This is because PGP is based on public-keycryptography.

PGP encrypts data using the International Data EncryptionAlgorithm with a random session key, and uses the RSA

algorithm to encrypt the session key.

In December 1994 Philip Zimmermann faced prosecution for

"exporting" PGP out of the United States but in January 1996

the US Goverment dropped the case. A US law prohibits the

export of encryption software out of the country.

Zimmermann did not do this, but the US government hoped to

establish the proposition that posting an encryption program

on a BBS or on the Internet constitutes exporting it - in

effect, stretching export control into domestic censorship.

If the government had won it would have had a chilling effect

on the free flow of information on the global network, as well

as on everyone's privacy from government snooping.

FAQ . UK FTP. USA FTP.

.

Justice Dept. announcement.

["Protect Your Privacy: A Guide for PGP Users", William

Stallings, Prentice-Hall, ISBN 0-13-185596-4].

(1996-04-07)