This is my second request. Take me off your mailing list please!
Bob
>From: [EMAIL PROTECTED] >Reply-To: [EMAIL PROTECTED] >To: <[EMAIL PROTECTED]> >Subject: Re: [SOCALWUG] the 'A' protocol >Date: Mon, 28 Jun 2004 20:44:19 -0700 (PDT) > >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 sing!
le '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]
sadena.net]On > >>> 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 abl!
e 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 storag!
e! > >>> http://promotions.yahoo.com/new_mail > > > 