Here's the scoop: DSL router with dynamic WAN IP servicing up NATed DHCP connected to the WAN port on a Sonicwall firewall which is then serving up its own NATed network. Is it possible, knowing the public IP address (e.g. via dyndns) to access resources on the internal network (esp. remote desktop)?
Some clarifications on the request: I have no control over the DSL router and I'd like to avoid 3rd party infrastructure (e.g. logmein, etc).