Virtual Private Network (VPN)

Virtual private network

A virtual private network also known as a(VPN) is a private network thatextends across a public network or internet. It enables users to send andreceive data across shared or public networks as if their computing deviceswere directly connected to the private network.

VPNs can provide functionality, securityand/or network management benefits to the user. But they can also lead to newissues, and some VPN services, especially “free” ones, can actually violatetheir users’ privacy by logging their usage and making it available withouttheir consent, or make money by selling the user’s bandwidth to other users.

Some VPNs allow employees to securelyaccess a corporate intranet whilelocated outside the office. Some can securely connect geographically separatedoffice of an organization, creating one cohesive network. Individual Internetusers can use some VPNs to secure their wireless transactions, to circumventgeo-restrictions and censorship, and/or to connect to proxy servers for thepurpose of protecting personal identity and location. But some Internet sitesblock access via known VPNs to prevent the circumvention of their geo-restrictions.

A VPN is created by establishing a virtualpoint-to-point connection through the use of dedicated connections, virtualtunneling protocols, or traffic encryption. A VPN available from the publicInternet can provide some of the benefits of a wide area network (WAN). From a user perspective, the resourcesavailable within the private network can be accessed remotely.

Traditional VPNs are characterized by apoint-to-point topology, and they do not tend to support or connect broadcast domains,so services such as Microsoft Windows NetBIOS may not be fully supported orwork as they would on a local areanetwork (LAN). Designers have developed VPN variants, such as VirtualPrivate LAN Service (VPLS), and layer-2 tunneling protocols, to overcome this limitation.

From: https://en.wikipedia.org/wiki/Virtual_private_network