A virtual private network (VPN) is a private communications network often used within a company, or by several companies or organizations, to communicate confidentially over a publicly accessible network.

 

VPN message traffic can be carried over a public networking infrastructure (e.g. the Internet) on top of standard protocols, or over a service provider's private network with a defined Service Level Agreement (SLA) between the VPN customer and the VPN service provider.

 

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