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VPN Basic Concepts and Classification
The term VPN (Eng. “Virtual Private Network”) refers to a group of technologies that provide a network connection, or the so-called logical network, functioning on top of some other network, usually the Internet.
Although data is transferred to a VPN over networks with a low level of trust, thanks to the use of cryptography, the level of trust in a VPN can be arbitrarily high. Among the cryptography tools used are encryption, means to protect against changes in transmitted messages, public key infrastructure and authentication. Depending on the final destination, the VPN implements three types of connections: network-to-network, node-to-network and node-to-node.
VPN implementation and structure Continue reading