DMZ and Windows File Sharing

OK, just playing with the home network and I have a few questions.

My network is setup as follows:


The cable modem and router are upstairs, in the same room as my PC. My dads laptop (and printer etc) are all downstairs and the laptop is linked to the hub, which is in turn connected to the router. Sometimes I will be using my PC downstairs, sometimes upstairs.

My dads PC is running in the DMZ, is it possible to enable file sharing between the 3 pcs without the shares being acessible on the internet (as one PC is in the DMZ).

TIA

I've had filesharing enabled along with DMZ on one computer, i never had a problem, butthatdosent mean it wasnt being shared onthe internet, people couldnta seen it i suppose. so im not to sure how to do it without it being shared unless its password protected, you can do thatand then log on andsave your password and then it'll automaticly log you on asif there were no password

what's yer dads PC in the DMZ for? If its possible just to setup some port forwards to his box that'd be more secure for his PC

As far as I know (I may very well be wrong) being "DMZ" basically means the router doesn't block ANY ports (internet related) and wouldnt make a difference at all to any of the computers on the LAN. Any LAN shares will never be accesable to anyone over the internet. However because of the fact that no ports are blocked your Dads machine is succeptable to hackers and other bad things...

If at all possible just forward the specofic ports your dad needs and don't use DMZ. then you are much better protected.

in my experience doesn't a DMZ have to have two routers to work effectively. replace the hub with a router that will make it a DMZ. Will be more secure.

Actually DMZ just means that the computer set up to be in the DMZ is outside the protection of the router.

DMZ = De-Militarized Zone, when a workstation or server is in the DMZ, all the internet traffic wont travel through the Routers Firewall. The computer within the DMZ, is suceptable to internet attacks and trojans can send the data to the hacker with no effort.

Computers in the DMZ should run a software firewall like Zone Alarm which is by Zone Labs inc.

Why is the computer in the DMZ? is it running as a web server? Aslo if he VPN's to work it isnt very secure.. Take him out of the DMZ and if its a server do port fowarding or if he does a VPN use port fowarding for that too...