A virtual private network (VPN) expands a private network across a public network, for example the world wide web. Important executions of VPNs contain IPsec and OpenVPN.

From a user standpoint, the extensive network resources are accessed in exactly the same fashion as resources accessible within the private network. One important constraint of conventional VPNs is they are point to point, and don’t often support or connect broadcast domains. So networking, program, and communication, which are derived from program packets and layer 2, for example NetBIOS used in Windows networking, might not be entirely supported or work just as they’d on a real LAN.

VPNs enable workers to access their institution’s intranet while traveling outside the office. Likewise, VPNs connect geographically divided offices of an organization. VPN technology is also used by individual Internet users to link to proxy servers with the aim of shielding personal identity and place, to circumvent censorship and geo constraints, and to fix their wireless transactions.