On Wed, Sep 14, 2011 at 6:37 AM, Troels Schmidt - Vika Data
<ts at vikadata dot dk> wrote:
> Hi list
> Not too optimistic here, but here's the problem. I need to make an ipsec vpn
> between to mono's. But one mono is placec behind another router which we
> have absolutely no control over. Is it possible?

Yes, depending. ;-)  You might need to enable NAT-T (there's a
checkbox for that on the IPsec page). The router must permit the
protocols and ports for IPsec, IKE, and possible UDP encapsulation.

- M