Topic: Firewalls

[Sandra]

Having just set up a network for my two PCs on an ADSL router with an integral modem which I thought had a firewall built in it apears to not have one
It has NATS but on testing it on www.grc.com on their leak test its like the proverbial sieve.
I have installed Sygate (the freebie one) which I have previously used and ran that test again which it passed.
I then ran the Test My Ports feature which was ok but on the Probe My Ports it has all closed except 21,23 and 80.None of the closed ports are STEALTHED whereas as I am sure that they were the last time I tried it after installing Sygate  
My query is this :
Is a firewall really necessary seeing as it has NATS even though GRC says it leaks,people can only see into the router and not through it into my PC/PCs or can they ?
If a firewall is necessary how do I get my ports stealthed on Sygate as I had before ?
I kow if I wade through GRCs site I will probably be able to work it out by the end of summer but as its taken over two days to get my router working I have read up on enough stuff for this week already and if someone knows the answers off the top of their head it would be appreciated  


Edited to add:

I just went back to the GRC site and downloaded their IPagent utility and did as it said and it gave me this result :

If our IP Agent brought you directly to this page, without offering you a choice of IP's, your machine has only this single private IP address and it is invulnerable to outside discovery, connection, and attack.

So I am even more confused now  

[lobo]

@Sandra

Hi Sandra,
If you are behind a router then the only address showing to the internet is your providers IP address, all of your PCs are allocated a private IP address by the NAT (Network Address Translator) operation of your router, hence

"If our IP Agent brought you directly to this page, without offering you a choice of IP's, your machine has only this single private IP address and it is invulnerable to outside discovery, connection, and attack."

The router you are using has an inbuilt firwall but you can still use another besides

"The Conexant firmware includes the Free BSD version firewall. All UDP/TCP ports are protected from intrusion."

When you use an online PC check you authorise your PC to allow that site to access ports on your PC that may not normally be used for communications. If a normal port scan was initiated then all that would show would be the IP of the router and the ports on the router but there would be no access passed the router

There are exemptions to this and some routers can be "hacked" but for normal operations these can be discounted

As you know I run Norton Firewall and Anti-Virus software all the time and since I installed the router the firewall has not registered any attempted penetration of my network whilst before the router there were numerous attempts every day.

Brian

[Camstop]

Excellent reply Brian.....

Even i fully understood that..!!

[Sandra]

So the original leak test that the grc site showed was my router "leaking" then not my pc ?
Is there any advantage of still using a software firewall as well then as the less things that there are running the less there is to go wrong,slow the start up and shut down times and doesnt use any of the cpu  

[Clive]

I've removed Zone Alarm from my computer and just use the router firewall these days as I found that having both prevented me from accessing any Yahoo site apart from Messenger.  GRC shows that I'm still in full stealth mode.

[Simon]

Well, I know nothing about routers, but if nothing's getting through it, surely there's no point having an additional firewall.  It's a bit like being alone in the house, but still locking the bathroom door!  

[Sandra]

It's a bit like being alone in the house, but still locking the bathroom door!  

Simon dont you realise that if you are alone in YOUR house and in YOUR bathroom naked and a burglar breaks in that they could sue you for the shock of seeing you in the buff and make lots of money to help them recover.Have you NO sympathy at all for those poor burglars  

[Simon]

They'd need a bleeding long ladder - I'm six floors up!  

[Sandra]

I do hope that you have installed plenty of those cardboard boxes or airbags that the stuntmen use for jumping off high buildings onto in the films then Simon.
If one of those poor burglars fell while climbing up your drainpipe to break in to your flat and  twisted his ankle or broke his leg he could sue you for thousands