We have an application that works requires, say inbound port 103 (example). It is not working, and the programmers think it is because that inbound port is blocked by either a firewall or an access list on a router.
Without access to these devices, how is it possible to answer this? We can, of course ,try telnetting to that port from the outside. But is there anything else, and more specifically is there anything that will tell us exactly *where* and *why* that port is blocked?
Regards