A VPN (Virtual Private Network) is a system that allows permanent TCP/IP connection over a secured industrial extranet. This permanent connection is called a tunnel and it is the role of the eWON to create this VPN tunnel and keeping it permanent.

All devices connected to this eWON on one site can connect to any other device, that is connected to another eWON, on another site. This means that any device can exchange data with any other device, through eWON VPN gateways.

Basically, an eWON can establish a VPN tunnel with :

• another eWON or a software called eCatcher: in this mode, it is a point-to-point connection.

• A dedicated VPN software called eSync. In this mode, the connection topology looks like a star where all VPN tunnels converge toward a central point, a server, on which eSync is installed. eSync dispatches then the information arriving at the end of every tunnel and redirect it to any other appropriate tunnel. eSync thus plays the role of a big router for many remote small networks and merge them virtually into one big network.