Let's look at an IPSec VPN tunnel implementation example:
The cloud icon represents a public unsecured network, say the Internet. Let's say there are two remote office sites, Site A and Site B. This could be two branch offices of a company situated in different cities or even different countries. Both of these remote sites have their own independent ISP connections. They also have a local pfSense firewall implemented in remote locations. Similarly, they also have an internal LAN, consisting of various internal network devices. Site A has the internal IP address range of 192.168.1.0/24. Site B has the internal ...
