Virtual private networks

In computer networking, TUN and TAP are kernel virtual network devices. Being network devices supported entirely in software, they differ from ordinary network devices which are backed by physical network adapters.

Virtual private network (VPN) is a network architecture for virtually extending a private network (i.e. any computer network which is not the public Internet) across one or multiple other networks which are either untrusted (as they are not controlled by the entity aiming to implement the VPN) or need to be isolated (thus making the lower network invisible or not directly usable).

EncroChat was a Europe-based communications network and service provider that offered modified smartphones allowing encrypted communication among subscribers. It was used primarily by organized crime members to plan criminal activities. Police infiltrated the network between at least March and June 2020 during a Europe-wide investigation. An unidentified source associated with EncroChat announced on the night of 12–13 June 2020 that the company would cease operations because of the police operation.

ZeroTier, Inc. is a software company with a freemium business model based in Irvine, California. ZeroTier provides proprietary software, SDKs and commercial products and services to create and manage virtual software-defined networks. The company's flagship end-user product ZeroTier One is a client application that enables devices such as PCs, phones, servers and embedded devices to securely connect to peer-to-peer virtual networks.

KeepSolid VPN Unlimited is a personal virtual private network software product available for iOS, macOS, Android, Windows, and Linux.

Onavo, Inc. was an Israeli mobile web analytics company that was purchased by Facebook, Inc. (now Meta Platforms), who changed the company's name to Facebook Israel. The company primarily performed its activities via consumer mobile apps, including the virtual private network (VPN) service Onavo Protect, which analysed web traffic sent through the VPN to provide statistics on the usage of other apps.

VyOS is an open source network operating system Linux distribution based on Debian.

AnchorFree is an internet privacy and security company that provides businesses and consumers with advanced technologies to enable secure and private web browsing. The company's flagship product is Hotspot Shield, a popular virtual private network (VPN) service and the top-grossing app for productivity in the Apple App Store. The company is led by David Gorodyansky, who founded the firm in 2005 with his friend Eugene Malobrodsky. AnchorFree is headquartered in Redwood City, California, with offices in Ukraine and Russia. Its most recent fundraising round in 2018 brought in $295 million, bringing total funding to $358 million.

WinGate is an integrated multi-protocol proxy server, email server and internet gateway from Qbik New Zealand Limited in Auckland. It was first released in October 1995, and began as a re-write of SocketSet, a product that had been previously released in prototype form by Adrien de Croy.

Vyatta is a software-based virtual router, virtual firewall and VPN product for Internet Protocol networks (IPv4 and IPv6). A free download of Vyatta has been available since March 2006. The system is a specialized Debian-based Linux distribution with networking applications such as Quagga, OpenVPN, and many others. A standardized management console, similar to Juniper JUNOS or Cisco IOS, in addition to a web-based GUI and traditional Linux system commands, provides configuration of the system and applications. In recent versions of Vyatta, web-based management interface is supplied only in the subscription edition. However, all functionality is available through KVM, serial console or SSH/telnet protocols. The software runs on standard x86-64 servers.