Which protocol is most commonly used for site-to-site VPNs in FortiGate?

The most commonly used protocol for site-to-site VPNs in FortiGate is IPsec. IPsec (Internet Protocol Security) provides a robust and secure framework for authenticating and encrypting IP packets exchanged over the network. It operates at the network layer and can ensure that all data transported between sites is protected from eavesdropping and tampering.

One of the primary reasons IPsec is favored for site-to-site connections is its ability to establish secure tunnels between gateways rather than between end-user devices. This is particularly important for connecting entire networks rather than just individual cases, allowing for secure connections between two or more physical locations.

Furthermore, IPsec supports various encryption protocols and algorithms, providing flexibility depending on the specific security requirements of the organization. It also supports different modes of operation, such as transport and tunnel mode, which cater to different needs depending on the scenarios.

In contrast, options like SSL are typically used for remote access VPNs rather than site-to-site VPNs, making them less suitable for this purpose. L2TP and PPTP, while they can establish VPN connections, do not provide the same level of security and are less commonly favored for enterprise-level site-to-site implementations compared to IPsec. Thus, the choice of IPsec