Virtual private network

It is possible to make a VPN secure to use on top of insecure communication medium (such as the public internet) by choosing a tunneling protocol that implements encryption.

This kind of VPN implementation has the benefit of reduced costs and greater flexibility, with respect to dedicated communication lines, for remote workers.

Typically, individuals interact with remote access VPNs, whereas businesses tend to make use of site-to-site connections for business-to-business, cloud computing, and branch office scenarios.

However, these technologies are not mutually exclusive and, in a significantly complex business network, may be combined to enable remote access to resources located at any given site, such as an ordering system that resides in a data center.

Operating systems vendors and developers do typically offer native support to a selection of VPN protocols which is subject to change over the years, as some have been proven to be unsecure with respect to modern requirements and expectations, and some others emerged.

Their administration interfaces do often facilitate setting up virtual private networks with a selection of supported protocols which have been integrated for an easy out-of-box setup.

In some cases, like in the open source operating systems devoted to firewalls and network devices (like OpenWrt, IPFire, PfSense or OPNsense) it is possible to add support for additional VPN protocols by installing missing software components or third-party apps.

This is often the case for appliances that rely on hardware acceleration of VPNs to provide higher throughput or support a larger amount of simultaneously connected users.

Authentication can happen immediately on VPN initiation (e.g. by simple whitelisting of endpoint IP address), or very lately after actual tunnels are already active (e.g. with a web captive portal).

[28] Mobile VPNs are widely used in public safety where they give law-enforcement officers access to applications such as computer-assisted dispatch and criminal databases,[29] and in other organizations with similar requirements such as field service management and healthcare.