A virtual private network (VPN) is a type of network connection that creates the illusion that you’re directly connected to a network when in fact you are not. For example, suppose you’ve set up a local area network at your office but you also occasionally work from home. But how will you access the files on your work computer from home?
You could simply copy whatever files you need from your work computer onto a flash drive and take them home with you, work on the files, copy the updated files back to the flash drive, and take them back to work with you the next day.
You could e-mail the files to your personal e-mail account, work on them at home, and then e-mail the changed files back to your work e-mail account.
You could get a laptop and use the Windows Offline Files feature to automatically synchronize files from your work network with files on the laptop.
Or, you could set up a VPN that allows you to log on to your work network from home. The VPN uses a secured Internet connection to connect you directly to your work network, so you can access your network files as if you had a really long Ethernet cable that ran from your home computer all the way to the office and plugged directly into the work network.
There are at least three situations in which a VPN is the ideal solution:
One or more workers need to occasionally work from home (as in the scenario described above). In this situation, a VPN connection establishes a connection between the home computer and the office network.
One or more mobile users — who may not ever actually show up at the office — need to connect to the work network from mobile computers, often from locations like hotel rooms, clients’ offices, airports, or coffee shops. This type of VPN configuration is similar to the home user’s configuration, except that the exact location of the remote user’s computer is not fixed.
Your company has offices in two or more locations, each with its own local area network, and you want to connect the locations so that users on either network can access each other’s network resources. In this situation, the VPN doesn’t connect a single user with a remote network; instead, it connects two remote networks to each other.