Hey Jim, Yeah im sure u are right, truth is my knowlegde on the issue is outdated. I just remembered that there where some issues with mixed mode. Could you clairfy if the Broadcom screw ups are fixeble with firmware updates, since this is a vendor caused issue... Im sure it will be of interest to the users here that run mixed, but haven't updated their firmware since they bought their AP before the issues where corrected... if they ever were.
Martin > 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 >>>>> >>>>> >>>>> >>>>> >>>>> __________________________________ >>>>> Do you Yahoo!? >>>>> New and Improved Yahoo! Mail - 100MB free storage! >>>>> http://promotions.yahoo.com/new_mail
