The Top Five Free Encryption Tools

Whether you need an encrypted tunnel to manage remote systems, routers, or firewalls, or you need to digitally sign an email or even encrypt an entire hard drive, there are free and open source tools available to accomplish these tasks. Let's take a look at the top five free cryptographic tools available.

TrueCrypt is an open source disk encryption program that can create virtual encrypted disks, encrypt entire storage devices, or partitions including boot partitions. TrueCrypt supports Windows Vista, Windows XP, Mac OSX and Linux. Encryption is performed transparently, in "real-time". If you need to encrypt your Windows system, this is the way to go.

Secure Shell is the de facto replacement for telnet and other plaintext terminal applications on all Unix-like operating systems. OpenSSH is the free, open source version of secure shell. Secure copy and secure FTP functionality is included. Strong authentication is supported, including Public Key and Kerberos authentication.

Stunnel allows you to encrypt any TCP connection using SSL. If you have a service or daemon that is not secure sockets layer (SSL) capable, but you need to protect sensitive information being sent, this is a great tool for doing that. Stunnel does require an SSL library in order to function, such as OpenSSL.

Gnu Privacy Guard is the GNU version of Pretty Good Privacy or more specifically the OpenPGP standard. It's a public key encryption system with support for integration with other applications, public key directories, and even has a related Windows version, Gpg4win.

Pretty Good Privacy (PGP) has long been the standard for free public key encryption. You can encrypt files or email, and can create digital signatures. Public key encryption hasn't penetrated the day-to-day Internet user's life yet, but as time goes on we'll see more and more use of tools like PGP to protect communications and verify identity. Note that I was unable to find a freeware version on their web site, but there allegedly is one.

Interestingly, I've found that the best encryption tools available of each type are in fact the free ones. I've used OpenSSH and PGP for years, and haven't seen a reason to switch to a commercial product yet. Granted, there are some excellent encryption tools out there that aren't free. The question remains, why would you pay for something if you don't have to? Perhaps you need some guarantee of support, or assistance with integration, or training. Even if this is the case, I advise you to check out the free and open source options that are out there.