Tricky routing/vpn question

[Kevin Brown]

Kurt Granroth wrote:

> Here's a puzzle:
> 
> Say you need to get an X session using XDMCP over a VPN.  However, that 
> VPN only has Windows client.  You are using Exceed and that works but 
> you would prefer to use Linux (or OS X) with a "real" X setup.  But see 
> above: the VPN *requires* Windows to run.
> 
> So you investigate the "Internet Connection Sharing" that comes with 
> Win98SE thinking that you could just do a 'route add -net' pointing to 
> the Windows computer.. but it doesn't work that way since the ICS works 
> using DHCP and you like your Linux box's current IP address just fine, 
> thank you very much.
> 
> But with that, you are somewhat stuck!
> 
> Or at least, *I* am stuck.  Can anybody think of a way that I can do 
> some sort of redirection or port forwarding on my Windows box that would 
> allow me to access the VPN from Linux?

What kind of VPN device is at the other end?  I know for Cisco VPN devices you 
can use IPsec on linux to create a connection with it.