"GnuPG is a complete and free replacement for PGP. Because it does not use the patented IDEA algorithm, it can be used without any restrictions. GnuPG is a RFC2440 (OpenPGP) compliant application." -- http://www.gnupg.org
The GNU Privacy Guard is the open source alternative to PGP, the Pretty Good Privacy
encryption tool. It's designed to support a lot of encryption algorithms, including; ElGamal
How the GPG works:
There is a private key
generated, and there is a public key
generated. With the public key
, you encrypt
the message to be transferred to the owner of the private key
. This means that only the owner of the private key
can read what you are sending him/her. The private key
must be kept secret, while the public key
should be spread to those you wish to have encrypted conversations with. The private key
is the only key that can decrypt the contents of the encrypted message
, so care for it wisely.
This is also more or less the concept of PGP.
Supported systems/platforms are:
GNU/Linux with x86, alpha, mips, sparc64, m68k or powerpc CPUs.
FreeBSD with x86 CPU.
OpenBSD (x86 CPU?).
NetBSD (x86 CPU?).
Windows 95/98/NT/2000/ME with x86 CPU.
AIX v4.3,_BSDI v4.0.1 with i386,
HPUX v9.x, v10.x and v11.0 with HPPA CPU,
IRIX v6.3 with MIPS R10000 CPU,
OSF1 v4.0 with Alpha CPU,
SunOS, Solaris on Sparc and x86,
USL Unixware v1.1.2,