Virtual Private Network (VPN) consists of following main components:
- Network Access Server (NAS): A NAS server is responsible for setting up tunnels in a VPN that is accesses remotely. It maintains these tunnels that connect clients to VPN.
- Firewall: It is the software that creates barrier between VPN and public network. It protects the VPN from malicious activity that can be done from the outside network.
- AAA Server: This is an authentication and authorization server that controls the access and usage of VPN. For each request to use VPN, AAA server checks the user for correct permissions.
- Encryption: In a VPN, encryption algorithms protect the important private data from malicious users.