IPsec Site-to-Site VPN Example with Pre-Shared Keys

A site-to-site IPsec tunnel interconnects two networks as if they were directly connected by a router. Systems at Site A can reach servers or other systems at Site B, and vice versa. This traffic may also be regulated via firewall rules, as with any other network interface. If more than one client will be connecting to another site from the same controlled location, a site-to-site tunnel will likely be more efficient, not to mention more convenient and easier to support.

With a site-to-site tunnel, the systems on either network need not have any knowledge that a VPN exists. No client software is needed, and all of the tunnel work is handled by the tunnel endpoints. This is also a good solution for devices that have network support but do not handle VPN connections such as printers, cameras, HVAC systems, and other embedded hardware.