Connecting Two Asterisk Servers


I am just curious - following the discussions, would it mean that two Asterisk servers can be connected via TCP/IP (or the Internet for that matter) and each can make PSTN to PSTN calls if each server is so equipped?



With an Asterisk PBX in say both the US & UK (my scenairio) connected via a VPN tunnel, means my UK PSTN and IP phones users get toll-free calls to the US and can use their PBX to make local-rate calls through out the US and vice versa of course.