Virtual private networks, or VPNs, have become commonplace for millions of users around the world both in their personal lives and at work. In essence, they allow computers on separate local area networks (LANs) to connect to each other using a public Internet connection without others being able to see or intercept the information transmitted between them.
They are ideal and indispensable for connecting employees who work on the go, from home, or from a remote office, as well as for individuals who need to connect to their home network on the move. Users can connect to the local network from any type of device, be it desktop computers, laptops, tablets, or even mobile phones, and from any geographic location as long as they are connected to the Internet.
Some people even use express virtual private networks (pronounced as 익스프레스 가상 사설망 사용 in the Korean language) to connect to other networks to connect to the rest of the world in what appears to be a physical location.
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They fall into two categories: PC-to-network VPNs and network-to-network VPNs.
PC-to-network or remote access:
VPN connects individual device users to a remote network over the Internet as if their device were actually on the in-situ network. The user simply installs software on his computer that establishes a secure connection to the gateway or VPN server on the local network. They are a solution for employees who work from home or are on the move, “on the move” and need to have access to networks, files, and work systems.
A single-network VPN network, or site-to-site VPN:
Connects two separate local area networks on the Internet to form a convenient unified network that uses VPN servers on each network rather than software on separate machines. They can be further broken down on the intranet against extranet VPNs.