Re: [tlug] WiFi considerations

["Daniel A. Ramaley" <daniel.ramaley@example.com>]

On Monday 09 July 2007 10:55, Godwin Stewart wrote:
>So, are there Linux-based tools that work with WPA or WPA2?

Yes, but getting them to run and interact with the hardware correctly is 
not always trivial. A program called "Network Manager" has been 
recommended to me by different people, and it is included in the Linux 
distributions i've checked (if not in the default install, then as 
something easy to add later).

>Secondly, the radio frequencies. From what I've read, WiFi operates in
>the 2.4GHz range.
>However, I've seen that some WiFi hardware can operate in the 5GHz
>range. Has anyone here had to do that?

Which frequencies WiFi uses depends on which WiFi standard your network 
operates on. 802.11b and 802.11g use 2.4 GHz, while 802.11a uses 5 GHz. 
The new 802.11n can operate on either. 802.11b and 802.11g equipment is 
what i've encountered the most. (The main significant difference 
between the two is speed: 802.11g is roughly 5 times faster than 
802.11b.) Here's an article that has a table showing which standard 
uses which frequency:
    http://en.wikipedia.org/wiki/802.11

Both at work and at home i have access to 802.11g networks. I've not 
personally experienced interference problems. At home i have a 
microwave and 2.4 GHz cordless phone. I also occasionally use a 
Bluetooth mouse and keyboard. I've tried running the phone, the 
microwave, and doing a file transfer over wireless simultaneously 
without problems. Even when i put my laptop on top of the microwave 
i've not experienced problems. I've also tried talking on the phone 
while using the bluetooth mouse and keyboard and wireless network 
without problems. However... interference is one area where your 
mileage definitely will vary. From anecdotes i've read, i think i'm 
just lucky.

>The idea is to be able to disconnect the laptop from the ethernet
>switch, shove a PCMCIA WiFi adapter in it and take it upstairs. Am I
>right in assuming that it's simply a case of stuffing one end of a
> CAT5 in the WAP and the other in my ethernet switch for the wireless
> segment of the network to be grafted onto the rest of the LAN, or
> will it require installing a WiFi NIC in the NAT/FW PC and adjusting
> routing tables accordingly?

Either plan of yours will work. My network is similarly structured to 
yours (and i expect many home networks are). I have a separate access 
point plugged into the ethernet switch and have not had any problems 
stemming from the basic setup. If you don't want to spend a lot of time 
futzing with configuration, i recommend going that route. You'll still 
have to configure the base station. Most stations come in an 
insecure-by-default configuration, but it is usually not difficult to 
turn on WPA, MAC filtering, or whatever other security the device 
offers and you choose to enable. If you have an OS X machine on which 
to run the configuration software, i recommend Apple's Airport Express 
base station. It is not the cheapest, but it works well.

>Fourthly, Linux hardware compatibility. How good is it nowadays?

That's still the hard part. Each chipset seems to be supported 
differently. Very few have fully open source drivers. To determine if a 
specific product works easily under Linux, remember that Google is your 
friend.

------------------------------------------------------------------------
Dan Ramaley                            Dial Center 118, Drake University
Network Programmer/Analyst             2407 Carpenter Ave
+1 515 271-4540                        Des Moines IA 50311 USA