IPSec VPN gateway solution?

Question

We need to connect to a client's LAN through IPSec VPN, and our router does not support IPSec tunnels. We found a software IPSec VPN client (ShrewSoft) which allows us to connect from one computer.

My question is how to configure this computer to act as a gateway to the client's LAN. Is this even possible?

I'm not a networking expert, but it seems to me that setting a static route for clients subnet on a computer in our LAN to use the above computer (with VPN client) as a gateway would cause all the traffic to the client go to the gateway computer. The problem is how to configure the gateway to accept this traffic and send it through IPSec tunnel (which it already does for locally originated traffic).

BTW, these are all Windows machines.

Hope I made sense in the explanation. Any ideas?

Answer 1

Its possible but messy. Better to get a router which does have a good IPSEC stack.
Anyway, You need to enable IP Routing on Windows machine (lets call it Bob) which does connect to your client.

For WinXP: Edit Registry: HKEY_LOCAL_MACHINESYSTEMCurrentControlSetServicesTcpipParameters Set IPEnableRouter to 1

On Computers from your network you need static route(s) to your client network with gateway Bob.