VPN Introduction

A Virtual Private Network (VPN) in computer networks is a technology that establishes secure connections over public networks, such as the Internet. Typically utilizing encryption technologies and tunneling protocols, a VPN encapsulates user network traffic within encrypted tunnels, ensuring that network communications remain resistant to interception, eavesdropping, tampering, or forgery during transmission.

A VPN can be regarded as a private channel established over the public internet, connecting a local network where the user is located with a remote network. The working principle of a VPN involves encapsulating user data packets within a VPN protocol header using encryption technology and then transmitting these encrypted packets to a VPN server. The VPN server decrypts the packets and forwards them to the target server; subsequently, the response packets are re-encrypted and sent back to the user through the VPN tunnel. Consequently, users can securely access remote networks over the internet without worrying about data being intercepted or tampered with.

VPNs are widely applied across various domains, including enterprises, government agencies, and individual users. In enterprises and government agencies, VPNs are commonly used in scenarios such as remote work, cross-regional access, and data transmission, providing users with a secure, stable, and efficient network connection. For individual users, VPNs are typically employed in scenarios aimed at protecting personal privacy, bypassing network censorship and restrictions, etc., offering an anonymous and unrestricted network environment.