NetworkActiv PortImport for Windows

The description of NetworkActiv PortImport - Play With New Friends

NetworkActiv PortImport allows you to access ports on computers that are behind firewalls/routers or in other situations that block your access. This essentially lets you import a port from an otherwise inaccessible computer - simply by having that computer make a single TCP connection (initiate a session) to your computer. Once that session is established, you can forward as many ports as you like and then connect to those ports by connecting to ports on your local computer. The component of PortImport made to be run on the remote computer has been designed to be extra easy-to-use and can even be easily scripted so that no configuration is necessary when it's run. PortImport is especially useful for situations where you want to help or access files (using a Web or other server) from someone (behind a non-configurable router/gateway) but where the other person is in need of a means that is easy and not-too-technical to get you connected to their computer.