[extazy33]

Hello,

I am trying to figure out what is the best way to maximize bandwidth.
Let's take this example:

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Mode is infrastructure. We are in G-Only mode and in 2,4 GHz (we are not considering the 5 GHz here).
Data rate is 54 Mbits/s -> thats 22 Mbits/s usefull (read on one article).

With 5 clients, each of them has usefull bandwidth of:
22 / (5 x 2) = 2,2 Mbits/s per client right ?

Now my first question is:

1. If 4 out of these 5 clients need only 1 Mbits/s, and the 5th needs
3 Mbits/s, is it possible to achieve this with some QoS or whatever, or since these
5 clients are connected to the same AP, no matter if they are using their bandwidth or not, this AP will never be able to give them more than 2,2 Mbits/s.

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Now if this AP has 3 wireless cards on channels 1, 6 and 11, if we set :
- 2 clients on chan 1
- 2 clients on chan 6
- 1 client on chan 11

Then we would probably achieve the previous requirement (in this case clients
on chan 1 and 6 would have 22 / (2 x 2) = 5,5 Mbits/s and the client on chan 11
would have 11 Mbit/s right ?).

I have read on wiki the article "The Myth of Non-Overlapping Channels" -> http://userver.ftw.at/~valerio/wons.html
So my second question is :

2. With those channels 1, 6 and 11, would i then really have 3 x 22 Mbits/s = 66 Mbit/s usefull data rate?

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Finaly if i extend this to a theoretical AP with 11 wifi cards (or 3 AP linked by lan at the same place, 2 with 4 wifi cards, 1 with 3), one on each channel from 1 to 11, i understand that the noise would be enormous. However the point is what about the total available bandwidth compared to the noise.
Will i have my 22 Mbit/s usefull for each channel, no matter the noise -> That would be 22 x 11 = 242 Mbit/s usefull!
Or due to noise i would only achieve for example 5,5 Mbit/s usefull (12 Mbits/s air link) for each channel?
What about using ever second channel 1-3-5... to get less noise so more bandwidth per channel?
So my 3rd question is about that compromise:

3. What is the best compromise between "number of channels and their distance/acceptable noise/channel data rate obtained" to get the maximum
available bandwidth possible at one AP?
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Thank you,
extazy33

[tomdidit]

Each client of the Access Point would have the potential to achieve the maximum speed possible.
It is not a ¨leased line¨"scenario.All connections are burstable to the max .

[extazy33]

Hello again,

Thanks for your answer. I found the original article link so i post it here:

http://www.digit-life.com/articles2/comm/tech-80211g-super.html

With the interesting part being:
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Thus, the generously allocated ~25 Mbit are divided between all participants of a wireless network. If the number of clients is 5 hosts and all of them are actively transmitting data, every participant will have the bandwidth of about 5 Mbit (in fact, it will be even a tad lower).

There is also the third bad news. The second bad news about 5 Mbit per each of 5 hosts is true only in case of Ad Hoc network, that is without an access point. If we take a more general case with an access point, those miserable 5 Mbit will have to be divided into two. Any exchange with clients in the Infrastructure mode (with an access point) goes via an access point. At first it should receive data and then retranslate it to the recipient. As a result, we get 2 and a little more megabit per user.
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So i am still worried about bandwidth:

With 5 clients connected to an AP, if 4 are only using lets say even 100 kbits/s, will the 5th be able
to perform at more than 2,2 Mbits/s. + see my previous questions.

Regards,
extazy33

[BrainSlayer]

if all conditions are okay, yes. but this is only synthetic.

but consider that you can reach more than 25 mbit/s. we got about 30 - 35 mbit/s max in our benchmarks