Using Virtual Private Networks to Secure Access to SharePoint

A common method of securing access to SharePoint farms from across unsecured networks is to create a virtual private network (VPN), which is effectively a connection between two private nodes or networks that is secured and encrypted to prevent unauthorized snooping of the traffic between the two connections. From the client perspective, a VPN looks and feels just like a normal network connection to SharePoint (hence the term virtual private network).

Data sent across a VPN is encapsulated, or wrapped, in a header that indicates its destination. The information in the packet is then encrypted to secure its contents. The encrypted packets are then sent across the network to the destination server, using a VPN tunnel.