Hardening your system in a mysterious way

Hi,
Well guys, to make a long story short:
Moved flat, changed isp.
Instead of a good router-like adsl modem using crappy cable modem.
Beforehand, the adsl modem would close all ports even with the software firewall shut down. With the cable modem, if I made grc and sygate tests with the firewall on I would get stealthed and with firewall off I would get open except ports stealthed by the isp.
However ...
I configured a home network and wired up some computers to share internet connection. Made the tests again.
This time, even with firewall shut down, I would get all the ports closed.
So, unless magic happened somewhere, configuring a home network hardened the internet gateway somehow. If this is the case, then I must recommend it to everyone.
Any wild ideas, guys?
Mrk

 

The magic is probably ICS if that is what you are using on one of your systems to share your connection with the others. It will do NAT and act as a router/gateway.

Description of Internet Connection Sharing

Regards,

CrazyM

 

Hi,
Indeed, ICS ...
Hooah!
Well then, everyone should get 2+ computers and ics them ...
Mrk

 

ICS is basically NAT. But remember the internet gateway computer itself is not anymore protected , so an attacker can still own that and from there put his way into your network.

 

Hi,
I was talking about the gateway computer.
Even if I shut down its firewall, all ports are closed.
Mrk

 

Really ?when i used ICS in the past (now i use a hardware router), I didn't notice any security gain by the gateway computer. In fact , i still had to use a firewall.

 

Hi,
Telling ya the truth honest.
Still, I'm using firewalls on ALL the connected computers, regardless of ics or no.
But it seems, as I said, I'm mysteriously magicked.
Mrk