The article isn't exactly accurate, in either its discussion of technology, nor the politics of the WiFi Alliance and IEEE 802.11.

Yes, BRCM shipped a "pre-11g" implementation, and correctly labeled it as something other than "802.11g". (Symbol was once successfully sued by Aironet and (then) Lucent for shipping a "pre-standard 802.11" but calling it 802.11.)

In Broadcom's case, they called it "54g", and the marketeers there claimed that 54g was about positioning that all of
the optional rates should be "mandatory". (Did you know that rates above 24Mbps are "optional" in both 11g and 11a?)


In any case, Broadcom's chipset/design (with the associated drivers) is IEEE 802.11g *and* WFA compliant.

TI would love to find a market. Perhaps if they would open source their drivers, or at least open the programming
information, they would have a chance.


Jim

On Jun 28, 2004, at 8:44 PM, [EMAIL PROTECTED] wrote:

Sorry Jim,

I was but specific enough it is not the standard that is the problem but
the chip makers read i.e. http://www.vnunet.com/analysis/1140873


Martin


The issue is not that the implementation is messed-up (switching modes), but rather that the AP must clear the air (via promiscuous CTS) before sending any OFDM-encoded frame.

If it doesn't, then the B units in the area might not set CCA, and, if
they send a frame while either the AP or one of its
'G' clients is attempting to receive a frame, interference will result.


You get 'mixed mode' as soon as a single 'B' unit is associated, even
if its not sending any traffic.

802.11a and 802.11b were ratified at the same time (Sept 1997).
802.11g came along later.

Jim

On Jun 27, 2004, at 9:23 AM, [EMAIL PROTECTED] wrote:

There are wireless units that supports both 5.8 and 2.4 at the same
time
those are the dual-band units, i.e.
http://www.linksys.com/products/group.asp?grid=33&scid=35

As Larry said, mixed mode is used if u have both G and B units in use
on
the same AP, the reason that G mode will not support B units, is that
B units do not understand the OFDM modulation used by G (to boost
performance to 54 Mbit/s). B uses CKK and Barker code. But in mixed
mode
the chipset uses different modulation for each session, this is not
very
well implemented so if you have G and B units on the same AP, the G
units
will take a big performance hit because of the switching between OFDM
and
CKK.

Martin Madsen

Your wireless router can only transmit/receive on one frequency
band...
thus you cannot mix 2.4 GHz B and G with 5.8GHz A... A stands alone,
and
I think it has gone the way of the Betamax.
Your router may be allowing you to set it for "B only" or "G only",
and
I am guessing mixed mode would be used if you have some B and some G
enabled clients on your network.
Larry

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Behalf Of car val
Sent: Saturday, June 26, 2004 6:11 PM
To: [EMAIL PROTECTED]; [EMAIL PROTECTED];
[EMAIL PROTECTED]; [EMAIL PROTECTED]; [EMAIL PROTECTED]
Subject: [SOCALWUG] the "A" protocol


Hi SOCALWUG Membership,

I'm missing something??

I know the "B" was the first protocol transmitting at
11Mbit/s freq 2.4MHz

Protocol  "A"  was second  transmitting at 54Mbit/s
freq 5.0 MHz
this was more for commercial use, and was transmitting
freq 5.0 MHz had less interference with wireless
phones (2.4 Mhz)

then "G" came along at 54Mbit/s freq 2.4MHz
this protocol was able to pick up both  "B & A"??


my question, my Linksys wireless Router (WRT54GS)

has wireless settings for transmitting at

1) Disabled
2) Mixed
3) "B"
4) "G"


shouldn't it be as follows??

1) Disabled
2) Mixed (would be "G")
3) "B"
4) "A"

Second Question, I never see Wireless "A"  AP,  or
Router  advertised??,  do they exist??

TIA
carval




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