Looking for more (very) local wireless info.

[James Knott]

Colin McGregor wrote:
> I am looking to tweak settings of my wireless network and to do that I
> want more information about the nearby wireless networks.
>
> My network at present is a 802.11g hub down in the basement, my laptop
> which gets shifted around the house (and as the weather gets better
> may make visits to the back yard). In addition there are occasional
> visitors to the network, like my brother's laptop. I have some 802.11g
> PCI desktop PC cards that I may bring into play. But as most of my
> work is done on a conventional (wired) desktop machine the wireless
> network is lightly used. Still, I would like things to perform as well
> as possible, without spending any additional money.
>   

I haven't seen many hubs lately.  Switches have been around for years.
> Even early on a Sunday morning a run of "Scan for Networks" under
> KWiFiManager will turn up 17 networks in my area, and I have seen over
> 50 networks in my area. Given that 802.11g has 11 channels available
> to it, 50+ networks means everyone's slice of those channels will be
> limited.
>   
Those channels, dating back to the 802.11 (no b, g etc.) days, when
you'd get 1 or 2 Mb bandwidth.  With 802.11b & g, the channels overlap. 
The only way to avoid overlap is to choose channels that are
sufficiently separated.  Generally, channels 1,6 & 11 are use.  However,
if all those see heavy use, you might chose an in between channel.
> KWiFiManager tells me four things about the local networks, their
> name, what mode do they use, the signal strength and is WEP encryption
> turned on. This is all useful information but not enough for my
> tweeking purposes.
>
> So, to start with, I want to find software that will tell me:
>
> - Which channels are most heavily used (if say 90% of all the networks
> are on channel 1, I will happily set my network to  channel 11 :-) )?
> - What is the volume of traffic going over each channel (again I want
> to avoid the high traffic channels)?
> - How much 802.11b vs. 802.11g traffic is on a channel (802.11b and
> 802.11g can coexist on a channel, at the expense of 802.11g
> performance)?
>   

You might try Kismet.

> In other words I want the tools that will let me make smart picks
> regarding how to get the best performance I can out of what I have.
>
> Before anyone says something like "Why not just go to the new 802.11n
> stuff?", my answer is, I can not cost justify that (I would need to
> buy a new hub and network cards), given that my funds are very tight,
> and the wireless network is lightly used. Further, these same sorts of
> issues will no doubt show up in the 802.11n world sooner or later
> (802.11n has a larger number frequencies, few users (at least for now)
> and higher performance to start with).
>
>   

Many newer WiFi routers and access points have the ability to
automatically switch to least used channels.  Also, 802.11n may be on
the same 2.4 GHz band as used by b & g, which means the same
interference issues remain.  The problem is less on the 5 GHz band used
by 802.11a.  Also, WiFi is subject to interference from other devices
that share the spectrum, such as cordless phones, baby monitors,
microwave ovens etc.  There is also some overlap between the 2.4 GHz
band and an amateur radio band.  In that situation, the amateur radio
users have priority over WiFi and if there's any interference to amateur
radio, you have to use other channels.  WiFi users do not get any
interference protection from any source.


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