How necessary is a firewall if you have a router?

I sit behind a router that stealths all my ports.

I have NOD32 AV installed.

I have Spyware Termionator installed with all active protections on and HIPS enabled.

I am considering installing SandboxIE and running my browser in it.

How critical is it to have a firewall with the above in place? I do presently use one that I like (Comodo), but I would like to free up some resources on my aging computer.

Thoughts?

 

It depends if you think outbound protection is necessary. A while back, I had the same question and, after research in this forum, decided that my hardware router/firewall was enough for inbound protection. For outbound, I dowloaded Jetico 1.0 and removed the inbound protection filter. I feel that I am well protected for my browsing habits and have not had a problem with malware. I do, however, use powershadow when necessary, AOL AVS, spywareblaster, and k-meleon (javascript disabled). There will shortly be a debate here among posters if a software firewall is also necessary.

 

I don't use one

However, I have made it so that every single port is closed on my computer except for the one open for openssh, so that means a no-one can access my computer anyways since nothing is listening and waiting to be exploited.

If you don't care about outbound (I don't), and you don't trust your network, then just run the built in windows firewall, or something like ghostwall or chx-i in order to keep your memory usage as light as possible. Or, disable everything listening on a port so that you won't be exploited and a firewall isn't very necessary.

Cheers,

Alphalutra1

 

~removed full quote of post just above~

How do you do this (close all the ports)? I have all of my ports stealthed by my router. Is that the same thing?

 

No, it isn´t the same thing. Your router (or any firewall) prevents the disclosure of the state of your ports.

Use TCPView to know if there is anything listening on a port. Then disable unneeded service and use Windows Worms Doors Cleaner or Seconfig to close vulnerable/exploitable ports.

 

lucas,
I have and have compared TCPView to Active Ports, http://www.protect-me.com/freeware.html (Link in case you are unfamilar) they appear to do basically the same thing Thanks.

 

That would be a solid security environment, even without the software firewall. You just have to ask yourself: "do I want the outbound filtering a software firewall will give me and will it make me happier to use one?" If the answer is "No", then there you have it.

As long as you understand that if something wants to connect out, it can do so without your knowledge, but as long as long you feel your machine will never get anything malicious lurking on it, you really don't have too much to worry about. The WWDC recommended to you is a nice way to close some "trojan-targeted" ports, as well as the option to disable some unneeded services. Some of the notables I have disabled in XP are:

1. Messenger

2. Net Logon

3. NetMeeting Remote Desktop Sharing

4. Remote Registry Service

5. Server

6. TCP/IP NetBIOS Helper Service

You do have to exercise caution when disabling services, as you could cripple your machine disabling the wrong one(s) There is some info on services here: Services-Eldergeek

 

Yes, they are very similar apps.