VDE is an ethernet compliant virtual network that can be spawned over a set of physical computer over the Internet.
VDE implements a virtual ethernet in all its aspects, virtual switches, virtual cables. A VDE can be used to create a VPN. VDE interconnects real computers running Linux, Free-BSD, MacOSX kernels (through a tap interface), virtual machines (qemu, kvm, user-mode linux, pearpc, gxemul...) as well as the other Virtual Square components like ViewOS implementations (UMview/Kmview) and Lwipv6.
VDE supports heterogeneous virtual machines running on different hosting computers.