Wireless network/newbie questions

[alegator]

Hi, I'm currently using a Win XP SP3 PC connected to the internet using a Cisco ADSL modem physically connected via a network cable to the PC's network card (so no wireless). I bought a netbook that has WiFi that I plan to use in my home. So I also bought a Cisco WRT54GL wireless router. My plan is to keep the PC physically connected to the internet and the Netbook accessing ADSL via wireless. So the basic config would be:
- The ADSL signal cable going to the Cisco ADSL modem
- A network cable going from the Cisco ADSL modem to the Cisco Router
- A network cable going from the Cicso router to the PC
- The netbook accessing the internet via wireless using the router.
My question is:
1) When I'm not using the netbook, can I disable (or turn off) the routers wireless transmissions so that it acts only as a physical router? If so, how?
2) Will placing the router between the modem and the PC in the above described manner affect the internet speed (lower)?
3) Will the router (acting in physical mode only, i.e., no wireless) add an extra layer of security for the PC? Will I still need to keep the PC's installed software firewall (I'm using NIS2011)?
4) Does installing the router imply changing many of Windows' settings? Is it easy to revert back to the PC' original state if I ever decide to uninstall the router to the original config?
Thanks.

[guns1inger]

1) Depends on the router. My Netgear routers have wireless switches that will turn wireless on and off. Not many routers have these, so you usually have to go into the settings through the browser and turn off the wireless there instead. this becomes annoying because you have to be physically connected to the router to turn the wireless back on again.

2) Assuming you have at least 100MB connections between the modem and the router and between the PC and the router, it won't slow down your internet connection. if your connection is ADSL2/Cable (i.e. better than 10Mbps) and you only connect at 10Mbps at either point in the chain then yes, you will lose some of your speed.

3) Most modems have firewalls built in, as do many routers, however these are designed to keep out standard attacks. They won't stop virii or malware getting in, and if it does, wont stop it phoning home again. I still keep comodo running on my desktop for this reason

4) Assuming you are using DHCP on your current ethernet connection, and you don't change this, you will most likely not even notice the change. Worst case you may get a different IP allocated, and nortons or windows will pop up and ask you about the new network. In any case, none of this is permanent. If you pulled the router out the next day and connected directly back to the modem all would continue to work as before.

[Poppa_Meth]

1) I'd flash that router with Tomato Firmware. Much better than stock. Also it allows you to configure the little Cisco Systems button on the front to act as an on/off switch for wireless signal.
2 & 3) What guns1inger said.

[edDV]

An example for #2

ADSL modem to router will be 10 Mbps or 100 Mbps depending on the modem. Most routers are either 100 Mbps or 1000 Mbps (gigabit).

Even if your router is 100 Mbps, you can still run a gigabit network by using a gigabit switch between the router and the PC's on the wired network. The PC to PC or media player or NAS traffic can be at gigabit speeds while communication to the internet through the router will be at modem speed. Meanwhile wireless traffic comes to the network through the router at G or N wireless speeds.

#3 observation

The firewall should be at the router. Many routers allow setting the wireless connections inside or outside the firewall (outside is called DMZ). Firewall port configuration can get complicated for activities like internet gaming. Still the Windows firewall at all PCs should be on.

[alegator]

Thanks everyone for the replies.

1) I'd flash that router with Tomato Firmware. Much better than stock. Also it allows you to configure the little Cisco Systems button on the front to act as an on/off switch for wireless signal.
2 & 3) What guns1inger said.

I read that 3rd party firmware is much better than Cisco's factory installed. Besides tomato (http://www.polarcloud.com/tomato), I also read good things about DD-WRT (http://www.dd-wrt.com/site/index). Which one is better? And if I flash the firmware, can I revert back to Cisco's firmware? Or is the change irreversible? Even though Cisco's firmware has much less features, it might be more stable? Thanks.

[Seeker47]

Thanks everyone for the replies.

1) I'd flash that router with Tomato Firmware. Much better than stock. Also it allows you to configure the little Cisco Systems button on the front to act as an on/off switch for wireless signal.
2 & 3) What guns1inger said.

I read that 3rd party firmware is much better than Cisco's factory installed. Besides tomato (http://www.polarcloud.com/tomato), I also read good things about DD-WRT (http://www.dd-wrt.com/site/index). Which one is better? And if I flash the firmware, can I revert back to Cisco's firmware? Or is the change irreversible? Even though Cisco's firmware has much less features, it might be more stable? Thanks.

I've been using the same model router as the OP (though still Linksys branded) with the DD-WRT firmware for the better part of a year. No stability issues I'm aware of -- at least not for regular computer < -- > Internet usage, either wired or wireless. The one possible exception is Netflix or DirecTV streaming from a downstairs location that is farthest from the router. This can be hit or miss. Sometimes it's fine, and sometimes it has serious problems. But I think this could just as easily be blamed on other factors: either that this is a G router solution where quite possibly an N router would be more suitable, or that old familiar problem I've seen at various installations where the TW cable (which DirecTV is using here for streaming / downloads, and which Netflix uses here for its streaming) gets out-of-sync with the other hardware, and the cure requires rebooting cable modem + router + the other hardware downstream in the proper sequence. I've even had to do this 2 or 3 times in a row on a few occasions. (If this happened more often than it does, it would quickly become very annoying.)

This is the first I had heard of that Tomato f/w.

[Nelson37]

I've used the DD-WRT for a while, and tomato briefly. You were able to flash back to standard firmware with both.

Why do you want to turn off the wireless? These can be password protected, and even limited to particular hardware allowed to connect. I wouldn't update the firmware just to get a switch for the radio.

The extra security from the router is minimal, the NAT (address translation) is probably better than the simple firewall. Make sure and change this from the standard addressing, and change the admin password on the router. But keep the PC security software.

[pirej]

I agree with Nelson37, there is no need for Wlan on/off switch, just put some good password, NOT your name, nick-name, last/first-name, birth-date, dog's/cat-name, 12345678, or anything else that almost everybody uses.
You can set your router to allow connection only to some MAC adresses e.t.c.