dold@94.usenet.us.com hath wroth:

>tightguard@yahoo.co.uk wrote:
>> I just bought a Belkin Wireless Laptop Network Card Adapter - 54g.for
>> my laptop and now want to buy a Belkin ADSL Modem with Wireless G
>> Router I see there is a few on eBay with 125g on the box. Would this
>> still be compatible or would I have to buy the one with 54g. Not
>> knowing much about it I suppose I would not benefit the extra speed if
>> I only have a 54g on the laptop would this be right?
>
>The basic, compatible, rate is the 54g. You would be able to use 54g in
>this mixed environment.

Yep. Agreed. Faster than 125Mbits/sec is not mentioned in the
IEEE-802.11g standard and is deemed "proprietary".

>Because the "extra" rates are vendor-specific, you would have to have a
>card from the same vendor as the router to take advantage of the
>non-standard rate. That might include two vendors that use the same
>chipset, or whose products are actually made by the same company.

I usually just turn those modes off even if they are compatible. The
problem is that the card spends an inordinant amount of time switching
in and out of these advanced modes trying to squeeze every last bit of
thruput out of the system. Besides, they only work for fairly short
ranges and then only if there is no interference.

>I once had a problem with an SMC "22Mbps" card that would not connect for
>more than a minute with a Netgear 54g. I had to disable the non-standard
>"Turbo" implementation in the SMC card, so it could connect at 11b. I
>haven't seen anyone else mention that sort of incompatibility.

Different proprietary standard. 22Mbits/sec is Texas Instruments
implimentation of PBCC (Packet Binary Convolutional Code) which was an
optional alternative to OFDM protocols included in IEEE 802.11g-2003
in section 19.6. It was necessary to obtain TI's vote to obtain
approve 802.11g-2003. There's also a PBCC 33Mbits/sec mode which I
haven't seen implimented.

Products which use the TI ACX1000 chipset have this mode.
Unfortunately, various implimentations (i.e. DWL-900AP+) would screw
up 802.11b connections if the 22Mbit/sec mode was enabled. It would
constantly try to make a faster 22Mbit/sec connection, fail, but take
so long doing it, that the 802.11b connection would think the client
has disconnected. It works just fine as "22Mbits/sec only" but does
badly when mixed with 802.11b.

--
Jeff Liebermann jeffl@comix.santa-cruz.ca.us
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558