Server-less and peer to peer VPN based on NAT traversal (RFC-3489). VNN is useful for the users in different branch offices to use their LAN based applications across the Internet without requiring them to reconfigure their routers or firewalls. They can run the applications just as they are on the local area network. When users with VNN software running on their PCs, based on VNN's virtualized LAN, the users will see a new subnet IP address on their PC. Each user's PC will be given a fixed host name, in the form of userid.groupid.vnn, so they can run their applications based on this fixed hostname, no matter where the PC is and no matter what IP address the PC gets.