The Stunnel program is designed to work as an SSL encryption wrapper between remote client and local (inetd-startable) or remote server. It can be used to add SSL functionality to commonly used inetd daemons like POP2, POP3, and IMAP servers without any changes in the program’s code.
What Stunnel basically does is that it turns any insecure TCP port into a secure encrypted port using OpenSSL package for cryptography. It’s somehow like a small secure VPN that runs on specific ports.
Step 1: Create an Ubuntu Droplet
So far I have tested it on Ubuntu 12.04 x32/x64, Ubuntu 12.10 x32/x64, Ubuntu 13.04 x32/x64.
Step 2: Update and Upgrade Ubuntu
Using these commands update your Ubuntu’s package list and also upgrade the existing packages to the latest version:
apt-get update apt-get upgrade