Editing Virtual private network (section)

{{short description|Extension of a private network across a public one}}
{{Redirect|VPN|other uses|VPN (disambiguation)|commercial services|VPN service}}
{{Use dmy dates|date=August 2017}}
{{Use American English|date=April 2021}}

'''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).<ref name="NIST">{{Cite web |title=virtual private network |url=https://csrc.nist.gov/glossary/term/virtual_private_network |url-status=live |archive-url=https://web.archive.org/web/20230102230546/https://csrc.nist.gov/glossary/term/virtual_private_network |archive-date=2 January 2023 |access-date=2 January 2023 |website=NIST Computer Security Resource Center Glossary}}</ref> 

A VPN can extend access to a private network to users who do not have direct access to it, such as an office network allowing secure access from off-site over the Internet.<ref name="Cisco">{{Cite web|title=What Is a VPN? - Virtual Private Network|url=https://www.cisco.com/c/en/us/products/security/vpn-endpoint-security-clients/what-is-vpn.html|access-date=2021-09-05|website=Cisco|language=en|archive-date=31 December 2021|archive-url=https://web.archive.org/web/20211231100706/https://www.cisco.com/c/en/us/products/security/vpn-endpoint-security-clients/what-is-vpn.html|url-status=live}}</ref>  This is achieved by creating a link between [[computing device]]s and computer networks by the use of network [[tunneling protocol]]s.

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 work]]ers.<ref>{{cite book |author= Mason, Andrew G. |title=Cisco Secure Virtual Private Network |url= https://archive.org/details/ciscosecurevirtu00andr |url-access= registration |publisher= Cisco Press |date= 2002 |page= [https://archive.org/details/ciscosecurevirtu00andr/page/7 7]|isbn=9781587050336 }}</ref>

The term ''VPN'' is also used to refer to [[VPN service]]s which sell access to their own private networks for internet access by connecting their customers using VPN tunneling protocols.