NAT Firewall Security?

[Matrox462]

I have a quick, and hopefully simple question... I'm finally getting DSL, and the modem and setup kit will be at my door in a few days. I already set up my wireless router and everything (making sure it's secure), but I have a question about something. Since this is the first time using a router that has a NAT firewall, I was wondering if I still need to run a firewall on all the clients that connect to the router... or is that going to create a double-firewall, and cause problems? I'm confused because I have file sharing set up for my wireless adapter, but that adapter also connects to the internet now. Will NAT keep internet users off my LAN shares? From my understanding, the internet cannot access my LAN, and any shares. I definitely want to keep a firewall running to restrict internet access to certain programs, but do I need to actually set up a firewall, or is the router alone enough? The software firewall I use is Zone Alarm... Should my wireless adapter be set as 'Trusted' or 'Internet'?

In cause it matters, the router is a Belkin 54g F5D7230-4. I'm very impressed with it so far, it even has built in wireless bridging.

Thanks for any help... I'm just confused about how well of security the router alone will offer.

 

[lomn75]

A double firewall won't break anything, but I find it unnecessary for most home LANs. The NAT box will keep outsiders out without issue, but the wireless AP can allow external (physically close) users into your LAN. Read up in the "secure my wireless" threads here for details.

 

[Matrox462]

A double firewall won't break anything, but I find it unnecessary for most home LANs. The NAT box will keep outsiders out without issue, but the wireless AP can allow external (physically close) users into your LAN. Read up in the "secure my wireless" threads here for details.

Well, I noticed that a few times my wireless connection won't work properly if the software firewall is running, which makes me believe that the two are conflicting.

I already got the wireless part completely secured, no default SSID, SSID broadcasting off, 128bit WEP (not WPA since I didn't want to change settings to use it), and MAC filtering...