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Re: Newbie Wireless Question [7:95793] posted 01/06/2005
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""Russ Uhte""  wrote in message 
news:200501061636.j06GaYwY003429@xxxxxxxxxxxxxxxxx
> Marko Milivojevic wrote:
>>>So, on a 54 Mbps system, that number truly is the maximum raw data
>>>rate for all combined traffic on that access point. Is that a correct
>>>statement?
>>
>>
>>     If I understand how those things work, it's not only on that AP, but
>> within range of any other transmitting device, be it on that AP, or the
> one
>> next to it. I might be very very wrong about this, though...
>
> This all depends on how your channels are spaced.  If your channels are
> properly spaced, the traffic on 1 AP will not affect the traffic on
> another AP.  For example, if you have 1 AP on channel 1, and the next
> one on channel 6, they can both operate at their full bandwidth.
> However, if you have an AP on channel 1, and then one right next to it
> on channel 2, there will be interference across the frequencies, and you
> will definitely notice a slow down on both devices.


Gotta be careful with terms like "full bandwidth"

We are talking about radio, same as that thing we listen to while driving 
around town. Each radio station broadcasts on a particular frequency. When 
you are in an area where two different stations broadcast on the same or 
overlapping  (nearby) frequency, you know the result - mud. Radio broadcasts 
get the "full bandwidth" because they are one way and all listeners are 
receive only.

Station to station radio such as one might remember from old movies ( 
Police, CB radio, etc ) required that one side complete transmission before 
the other side could respond. That's a roger. Over. We have all heard the 
lines.

802.11 provide the mechanisms that allow sharing of frequencies. Because it 
is radio, only one station can use any given frequency at any time. 
"Channels" are really frequencies.

Note that 802.11N - high speed wireless - will be able to increase 
"bandwidth" by using multiple antennas and multiple frequencies (channels). 
So called full duplex wireless bridges, such as sold by Proxim and Terabeam, 
have send and receive channels (frequencies)

Next time someone says that 802.11 is full duplex, you might... ah never 
mind ;)



>
> -Russ
> ---
> [This E-mail scanned for viruses by Declude Virus]




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