VTun provides a method for creating Virtual Tunnels over TCP/IP networks
and allows one to shape, compress, and encrypt traffic in those tunnels.
Supported types of tunnels are: PPP, IP, Ethernet and most other serial
protocols and programs.
VTun is easily and highly configurable: it can be used for various
network tasks like VPN, Mobile IP, Shaped Internet access, IP address
saving, etc. It is completely a user space implementation and does not
require modification to any kernel parts.