A Virtual Private Network (VPN) creates a secure, encrypted tunnel over public networks to extend private networks. VPNs enable remote users and sites to securely connect to corporate resources as if they were on the local network.
VPN Types
Remote Access VPNs allow individual users to connect to a corporate network from remote locations. Site-to-Site VPNs connect entire networks between different locations, commonly used to link branch offices to headquarters.
IPSec
IPSec is a suite of protocols that secures communications at the IP layer. It provides encryption, authentication, and integrity checking through protocols like AH (Authentication Header) and ESP (Encapsulating Security Payload).
SSL/TLS VPNs
SSL VPNs use the TLS protocol to create secure connections, typically through a web browser. They offer easier client deployment and can provide granular access control to specific applications.
VPN Protocols
Common VPN protocols include OpenVPN, L2TP/IPSec, PPTP, and IKEv2. Each offers different trade-offs in security, speed, and compatibility.
VPN Security Considerations
Effective VPN security includes strong authentication methods, regular key rotation, proper certificate management, and monitoring for unusual access patterns.