[Wolves] Wireless network access

[Darran Rimron]

On Fri, 2006-09-08 at 11:05 +0100, Mark Ellse wrote:
> We've got a Buffalo domestic wireless router that provides reasonably 
> good wireless internet access around one common room. But our walls are 
> thick and the range is poor. What should I do, go for a number of 
> similar routers scattered around the place, or something more industrial 
> and powerful? Does anyone have any experience?

IMO (YMMV - these are from _my_ _personal_ playings, and hardly
scientific):

* 802.11a rocks (aka mmm5Ghz! *drool*) for this sort of deployment, but
cheap, easily available kit is rarer than rocking horse droppings and
not all client chip-sets support this.
* 802.11b does better at long (open) distances if you don't mind the
speed loss.
* 802.11g if noticeably worse if you have "b/g compatibility mode"
enabled, killing "backward compatibility" gives results far superior to
802.11b.

If you get more "domestic wireless routers" there's a good chance that
they won't do "passing off" from one access point to another, I've had
problems with this before on cheap kit. I ended up buying WRT54Gs and
throwing White Russian on them.... However multiple access points (on
different channels) can often deal better with "Microwave
Pollution" (from DECT phones or good, old-fashioned Microwave ovens) in
the 2.4Ghz frequency, especially the lower channel numbers....

If I was in your position I'd see if your current access point supports
things like ad-hoc passing of clients between base-stations, etc. This
is often firmware dependant at the _client_ end, and thus sucks the
donkey dong :( the easiest way to test is to nick an access point from a
mate and intentionally switch your client between the two.

In short - multiple access points is going to give you a more reliable
and "hardened" network for general day-to-day use, if you happen to have
a wifi card that is clever enough to go, "Oh, look, multiple access
points on the same SSID, with the same crypt details but on different
channels, I'll pick the strongest...." - HOWEVER some (the
cheaper/commercial) APs cache your MAC address on the AP itself and when
you roam from one access point to the second you quite often you can't
get access to "the net" until the ARP cache on the first AP has expired.
(this is what was happening at the LRL06 hotel :( )

There's no "easy" way to check this, without nicking an access point
from "elsewhere" - for example, I found my WRT54G did exactly this until
I reblew the firmware with WhiteRussian :)

Of course, in some cases, it doesn't matter how beefy your transmitter
is, steel steam pipes, air conditioning ducts or a high density of
organic material (human bodies are a great radio dampener) all are going
to beat the living daylights out of your signal strength anyway. (At
LRL06 we had 80odd percent signal from one side of the room to the
other, until the punters arrived, and then we couldn't get 4 ping
packets in a row across it....)

I would:
 * Evaluate your current hardware: does it cache MAC/ARP; and thus
   making it useless for localised roaming between same SSID
 * Evaluate your environment: do you have objects that are going to
   kill wifi no matter how strong it is; Metal and Meat are the big
   no-no's here.

If you find option 1 is the case, an additional AP will help, but will
introduce some rather painful/annoying network issues, however, no
matter how good your antenna if you're finding yourself in option 2,
you're gonna need multiple transmitters....

While no proper answer, I hope this helps someone.... :)

-Dx