That's how I do it, but anyways I would prefer if it could recgonize subnets, which should be possible, as al subnets arecreated using MT, so it could get even network masks..
Actually, it can't do that, depending on where are you scanning. If you are in the same broadcast domain, it might do it, but from a distance, I don't see how it could know that. For example, if you have 2 /26 networks, and both are adressable by the same router, how could it find out it's not a /25 ?!?
After you specify connect parameters and device type, yes, dude knows what's inside the router, but before, i don't think so. If SNMP is enabled, and dude knows the comunity string, it might find out a lot of more information, but just from scanning, not.