tinc is a Virtual Private Network (VPN) daemon that uses tunnelling and
encryption to create a secure private network between hosts on the Internet.

Because the VPN appears to the IP level network code as a normal network
device, there is no need to adapt any existing software. This allows VPN
sites to share information with each other over the Internet without exposing
any information to others. In addition, tinc has the following features:

o Encryption, authentication and compression
    All traffic is optionally compressed using zlib or LZO, and OpenSSL is
    used to encrypt the traffic and protect it from alteration with message
    authentication codes and sequence numbers.
o Automatic full mesh routing
    Regardless of how you set up the tinc daemons to connect to each
    other, VPN traffic is always (if possible) sent directly to the
    destination, without going through intermediate hops.
o Easily expand your VPN
    When you want to add nodes to your VPN, all you have to do is add an extra
    configuration file, there is no need to start new daemons or create and
    configure new devices or network interfaces.
o Ability to bridge ethernet segments
    You can link multiple ethernet segments together to work like a single
    segment, allowing you to run applications and games that normally only work
    on a LAN over the Internet.