Virtual Private Networks (VPN) carry private network traffic over a public network, such as the internet, through secure connections.

You can use VPNs to provide secure connections between networks. You can also establish VPN tunnels between individual hosts, such as off-site employees, and the internal network.

Below Example: Site to Site IPSEC VPN between Two Firewalls

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Site-to-site VPN: You can configure policy-based (host-to-host and site-to-site) IPsec VPNs, route-based IPsec VPNs, and SSL VPNs.

1. IPsec VPN

Policy-based VPN: Encrypts traffic passing through the listening interface based on the firewall rule and the local and remote subnets specified in the matching IPsec connection.

Route-based VPN: Encrypts traffic passing through the virtual tunnel interfaces established based on the configuration. Static, dynamic, and SD-WAN policy routes determine the traffic sent through these interfaces.

2. SSL VPN:

Site-to-site SSL VPN: Establishes SSL/TLS connections between two Firewall devices in a client-server configuration.