further information on previous 802.11 thread?

Peter Chubb peter at chubb.wattle.id.au
Fri Apr 26 11:31:39 EST 2002

>>>>> "jan" == jan newmarch <newmarch at infotech.monash.edu.au> writes:

jan> On Thu, 25 Apr 2002 clug at repose.cx wrote:
>> 1. I'd like to use two cards, and avoid the base station, as I
>> really don't want to incure the extra expense. I seem to recall
>> that doing this is when the cards are placed in "ad-hoc" mode, but
>> there's this small piece of information floating around in my head
>> that says that you require new/particular cards to do this nicely
>> without a base station. Am I imagining things? Can
>> base-station-less operation be done fine with no consideration as
>> to the type of card? I just remember reading somewhere about a
>> "better" way to do it, or something. Maybe it was making one of the
>> cards act like an access point?

jan> You do have to be careful, because some of the current drivers
jan> are incomplete/buggy. For example, Aironet PCI card is fine in
jan> ad-hoc mode.  Wavelan cardbus card is fine in my laptop in both
jan> adhoc and managed. For D-Link, there are 3 drivers. Only one of
jan> those supports PCI cards in adhoc mode (and in one application
jan> gets only 400kbps transfer rates - well short of 11Mbps).

You will almost certainly need an external antenna on the
base-station.  I'm running in ad-hoc mode using a Compaq card.
Without the antenna, I can't use another station except within two
metres of the base (and even then the bit-rate drops to 1Mb); with the
antenna I can go out into the garden and use my laptop there.
This will depend on the geometry of your PCI slots vis-a-vis the case;
and where the card sticks out relative to the nearest wall.  Walls are
good absorbers of microwave energy; PC cases are metal and a good

The general rule is line-of-sight is needed to the antenna.

Windows, floors and ceilings don't seem  to be too much of a barrier;
brick and concrete are.

However, the drivers are buggy at present.
Every now and then with 2.5.7, the card just disappears (cardctl can;t
see it or the PCMCIA bridge any more).

Peter C

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