Implementing PGP

Last Updated: 24 February 2001

"The multiple human needs and desires that demand privacy among two or more people in the midst of social life must inevitably lead to cryptology wherever men thrive and wherever they write."

-  David Kahn, The Codebreakers


This is a simple guide to acquiring and installing PGP capability for personal encryption. There is extensive documentation supplied with the PGP software and from the download sites. This should be read before the software is installed.

Note: International versions of PGP are legal to use in Australia and most other countries, except the USA. Residents of the USA or Canada should obtain the US version from the appropriate site.

Downloading the Software

Since version 5.0, PGP has been implemented on the MS Windows platform. Previous versions were command-line based. Freeware versions of PGP are now available for Amiga, Atari, MS-DOS, MacOS, OS/2, Psion 5, Unix, Windows 3.x, and Windows 95/98/NT.

The latest Freeware PGP version is available from:

Commercial versions, required for use in a commercial environment, are available from:

The international sites provide links to download sites in various countries.

Implementing PGP

Installing PGP is now a very simple exercise, no different from installing any other Windows software.

After installation, you will need to generate a private/public key pair if you don't already have one. PGP offers the choice of generating an RSA or DH (Diffie-Hellman) key pair. The latter is recommended since it offers a number of advantages over RSA keys. However, if you choose a DH key, your encrypted messages will not be able to be decrypted by users who are still using an old version of PGP (e.g. version 2.6 or older).

PGP for Windows-95/98 offers the option of integrating with popular E-Mail clients such as Eudora or Outlook. This provides a convenient way of encrypting or decrypting messages. Users who do not have one of the supported packages can utilise the system tray icon to invoke PGP.

Publishing your PGP Public Key

There are a number of key servers around the world which enable you to publish your public key so that others can send you encrypted messages. These services synchronize keys with each other.

When PGP installs, it will provide the option of posting your public key to a key server.