What is tunneling as it applies to a virtual network?

Tunneling into a virtual network or private network refers to the process of using a public network to transmit data for use in the private network. This requires some encapsulation and other methods for protecting data as it moves through the public network space.

Typically, tunneling protocols allow for data to be sent in an IP format through the global internet, and be unpacked or disassembled for private network use at a private destination in the form of a VPN server. Tunneling can facilitate things like remote printing and file sharing inside private networks when the remote user is off-site and has to use the internet for a transport system.

The in-network server is the “unpacking” point for encrypted and encapsulated data. Protocols for tunneling include Microsoft Point-to-Point Tunneling Protocol (PPTP) and Cisco Generic Routing Encapsulation (GRE). Various types of SSH protocols allow for tunneling practices.

It is important to note that security for tunneling practices varies according to the particular setup. Data that is tunneling into a private network, whether it is a virtual network or other network, may not be beginning-to-end encrypted, so that it becomes vulnerable when it enters through the network server. There may be additional items attached to data packets moving through the internet that have to be interpreted and managed by the receiver. However, in general, tunneling provides an excellent way for network administrators to allow virtual and remote access without compromising sensitive data out in the public internet world.