Chris,

It might help us design these properly if we knew what the saturation levels 
were.  We have these for most other radios.

Thanks,

Tim
________________________________
From: Af <af-boun...@afmug.com> on behalf of Chris Trout <ch...@mimosa.co>
Sent: Wednesday, January 25, 2017 9:22:14 PM
To: af@afmug.com
Subject: Re: [AFMUG] B11, TDMA, and TCP

The PHY (Layer 1) is affected by EVM and PER which cause changes in modulation.
The MAC (Layer 2), where TDMA lives, makes use of the PHY but does not change 
it directly.
Changes in the amount and direction of traffic across the link do affect EVM 
and PER, however.

It is likely that the PHY rate is more stable on your link at 1300 Mbps (MCS7) 
than at 1560 Mbps (MCS8), and Auto TDMA is reacting faster to changing 
conditions since it sends a shorter duration of packets for training the PHY 
rate.

As others have recommended, reducing power will avoid saturating the receiver, 
and reduce (improve) EVM. I think that is what we may be seeing here on a very 
short link.

Chris Trout
Mimosa Networks, Inc.

From: Af <af-boun...@afmug.com> on behalf of Chris Wright <ch...@velociter.net>
Reply-To: "af@afmug.com" <af@afmug.com>
Date: Wednesday, January 25, 2017 at 1:55 PM
To: "af@afmug.com" <af@afmug.com>
Subject: Re: [AFMUG] B11, TDMA, and TCP

Traffic Split set to Auto:
PHY        1300/1300

Traffic Split set to 75/25, 8ms window:
PHY        1560/1300

Anyone can see why one should prefer setting the Traffic Split to 75/25 – it 
provides more bandwidth in one direction.

Chris Wright
Network Administrator

From: Faisal Imtiaz [mailto:fai...@snappytelecom.net]
Sent: Wednesday, January 25, 2017 12:35 PM
To: af@afmug.com
Cc: Chris Wright
Subject: Re: [AFMUG] B11, TDMA, and TCP

Hi Chris,

I want to compare something with my link...

Can you please share what's the listed PHY rates were on your PCN for the link.

Regards.

Faisal Imtiaz
Snappy Internet & Telecom
7266 SW 48 Street
Miami, FL 33155
Tel: 305 663 5518 x 232

Help-desk: (305)663-5518 Option 2 or Email: 
supp...@snappytelecom.net<mailto:supp...@snappytelecom.net>

________________________________
From: "Chris Wright" <ch...@velociter.net<mailto:ch...@velociter.net>>
To: af@afmug.com<mailto:af@afmug.com>
Sent: Wednesday, January 25, 2017 11:21:12 AM
Subject: Re: [AFMUG] B11, TDMA, and TCP
Power is already at the minimum (10dBm) on both sides. 2.2km link.

Chris Wright
Network Administrator

From: Af [mailto:af-boun...@afmug.com] On Behalf Of Faisal Imtiaz
Sent: Tuesday, January 24, 2017 9:56 PM
To: af@afmug.com<mailto:af@afmug.com>
Subject: Re: [AFMUG] B11, TDMA, and TCP

>SNR 41, 42, 41, 41

Turn down your power, and bring the SNR in the 30-35 range...
it will improve thruput and allow for the higher modulation.

Regards.

Faisal Imtiaz
Snappy Internet & Telecom
7266 SW 48 Street
Miami, FL 33155
Tel: 305 663 5518 x 232

Help-desk: (305)663-5518 Option 2 or Email: 
supp...@snappytelecom.net<mailto:supp...@snappytelecom.net>

________________________________
From: "Chris Wright" <ch...@velociter.net<mailto:ch...@velociter.net>>
To: af@afmug.com<mailto:af@afmug.com>
Sent: Wednesday, January 25, 2017 12:41:37 AM
Subject: Re: [AFMUG] B11, TDMA, and TCP
Firmware 1.4.4
SNR 41, 42, 41, 41
Flow Control had no effect so it remains disabled for now.
Sent via mobile phone.

On Jan 24, 2017, at 9:05 PM, Faisal Imtiaz 
<fai...@snappytelecom.net<mailto:fai...@snappytelecom.net>> wrote:
What version for firmware is on the radio ?

and   What your SNR on the two chains (both directions, i.e. 4 readings).

I can tell you that we do not see the behavior you are describing below...
But I can also tell you that we had to do some 'tuning' on settings including 
flow control ..
our B11's plug into netonix Switches....

Regards.

Faisal Imtiaz
Snappy Internet & Telecom
7266 SW 48 Street
Miami, FL 33155
Tel: 305 663 5518 x 232

Help-desk: (305)663-5518 Option 2 or Email: 
supp...@snappytelecom.net<mailto:supp...@snappytelecom.net>

________________________________
From: "Chris Wright" <ch...@velociter.net<mailto:ch...@velociter.net>>
To: af@afmug.com<mailto:af@afmug.com>
Sent: Tuesday, January 24, 2017 8:02:58 PM
Subject: [AFMUG] B11, TDMA, and TCP
According to Mimosa, I should be telling my customers that if they’re using the 
most popular metric in the world for testing internet speeds, they’re doing it 
wrong (I concede that while this may be technically correct, my customers – and 
yours too – don’t do technically correct very well.”

When TDMA is set to 75/25, 8ms window, MAC Tx/Rx is 980/290. This gives me as 
much Tx bandwidth as I require for peak times, but no one client IP can 
download more than 20mbps of TCP traffic (from my 
speedtest.net<http://speedtest.net> at the edge, nor anyone else’s beyond my 
edge).

When TDMA is Auto, MAC Tx/Rx is 780/780 (lower Tx, which is undesirable as it’s 
100mbps shy of what I need during peak hours), but TCP throughput per client is 
greatly increased (150+mbps).

So I’m in a pickle. Either my scrupulous customers can get those coveted 
speedtest.net<http://speedtest.net> results they love seeing as they run them 
every thirty seconds ad-nauseum at the cost of overall Tx capacity of the link. 
Or I give myself some headroom in link capacity but the fastest speeds my 
100mbps clients can see is 20mbps.

What’s even stranger is that client upload seems unaffected. I can upload 
150+mbps from my test on the link no matter what TDMA is configured. I hit up 
Mimosa’s chat support was as chipper as they were unyielding in their idea that 
I should test in a way that caters to the B11’s shortcomings. I’ve been a 
Mimosa fanboy for a while now but boy am I feeling burned right now.

Chris Wright
Network Administrator




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