Can you VPN across two NAT boundaries?

[s]

Is it possible to run a VPN across two NAT boundaries? I am behind NAT and
so is client. I am thinking that at least one machine has to have a real IP
address. Is that correct?

 

[Steven Umbach]

It is easily done with pptp. I do it to vpn between home and work. The ip
addresses are the public addresses assigned by my ISP's which are configured in
my nat/routers. Then all that has to be done is to port forward port 1723 to the
actual computer acting as the vpn server on each network and also allow protocol
47 which is also commonly referred to as pptp passthrough on lot of the nat
devices. Ipsec vpn can also be easily done with even the low price devices. My
Netgear FVS318 [I spent $110] allows eight ipsec tunnels to be set up to other
ipsec endpoint devices. ---Steve

 

[Gary]

I use a pair of FVS318's at work and home, and let the routers IPSEC, works
a treat. Once autenticated, the users on either LAN can browse share
printers etc, usual permissions apply.
Note the two LANS must have different IP ranges, ie 192.168.0.1... for one
LAN, the other 192.168.1.1... as examples.