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Subject: Re: 11n channel width
From: Adrian Chadd <adrian@freebsd.org>
To: Johann Hugo <jhugo@meraka.csir.co.za>
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On 26 October 2012 06:18, Johann Hugo <jhugo@meraka.csir.co.za> wrote:

> And the difference between a 1x1 and a 2x2 802.11n adapter ?

It's more complicated - since if you're not doing aggregation, the
overheads per frame eat in to your efficiency % and when you're
transmitting at high MCS or multiple streams, you don't necessarily
get a linear increase in throughput.

If aggregation is correctly working, you should see ~ 150MBit/sec TCP
between two 2x2 40MHz nodes, and roughly half/quarter that for
1-stream 20 and 2-stream 20 (or 1 stream 20 versus 1 stream 40.)


Adrian