Hello Jeen,

Nice post. I have the same understanding as you. It seems you can trigger EDRRM
only on those 3 thresholds low 35 (if it falls below threshold 35) , medium 50 
(if it falls below 50) and high 60 (if it falls below 60) And these are all 
sensivity values. So that can be confusing like you said. Less sensivity less 
probable of doing changes.
But on the other hand you can trigger traps to be sent at a custom AQI value. 
Under clean AIR AQI alarm threshold (1 to 100). But this seems only to be a 
trap and thus informational for WCS.

English is not my native language. But when there is a threshold doesn´t it 
always mean that this is "null" value. If something crosses this value
then appropriate thing triggers ? right ?

For example if asked: If AQI for a given controller goes below 35 an EDRRM 
should trigger a local DCA update if it improves quality. Then you shouldn´t 
think about setting the value 34 (even though it is not possible here)
but set it to 35 or Low. people agree ? It seems you agree and also Andrew 
about when this happens.

I nicer way to ask this question would be: "An AP reports and AQI of less than 
35 should be eligible to change channels with local RRM if it improves the 
quality."  Answer would be set EDRRM to low (and of course enable clean air on 
radio, access points (if disabled)
A harder question would be. "Trigger an alarm if AQI value falls below the 
medium AQI". = aswer here would be setting the AQI Alarm trheshold to 50 (not 
49) 

I actually learned recently that the WLC help page can come in preety handy 
sometimes, it gives you facts that you need for example I looked this up and 
there seems no doubt about my Trehshold value question.

An example fro WLC help:

"Select the Enable AQI (Air Quality Index) Trap check box to enable the 
triggering of air quality alarms, or unselect the check box to disable this 
feature. The default value is selected.
If you selected the Enable AQI Trap check box in the step above, enter a value 
between 1 and 100 (inclusive) in the AQI Alarm Threshold text box to specify 
the threshold at which you want the air quality alarm to be triggered. When the 
air quality falls below the threshold level, the alarm is triggered. A value of 
1 represents the worst air quality, and 100 represents the best. The default is 
35."

And for the EDRRM WLC help output is:

"Configured sensitivity threshold setting at which the RRM is invoked.

The available values are Low, Medium, or High. When the interference level of 
the access point raises above the threshold level, RRM initiates a local 
dynamic channel assignment (DCA) run and changes the channel of the affected 
access point radio if possible to improve performance. Low represents a 
decreased sensitivity to changes in the environment while High represents an 
increased sensitivity. The default value is Medium."

regards. Kristjan
------------------------------

Message: 2
Date: Thu, 17 Jan 2013 14:19:40 +1000
From: Jeen Sern Chew <[email protected]>
To: [email protected]
Subject: [OSL | CCIE_Wireless] IPExpert LAB 4: Question 4.8 CleanAir
        EDDRM   Sensitivity
Message-ID:
        <cals5-fpf1ncgxj5owhmiigghnpwirvs-6q1n0wvprbq9w-d...@mail.gmail.com>
Content-Type: text/plain; charset="iso-8859-1"

Hello all,

Firstly thanks for all discussions as it is really helpful for the CCIE 
Wireless lab. I have only been reading on the discussions and this will be my 
first post.

In the IPExpert workbook version 2, Lab 4, Question 4.8, the third question 
goes "An AP that reports an AQI of less than 40 should be eligible to change 
channels before the default RRM algorithm is run". The Solutions Guide mentions 
to use EDRRM of 'Low' sensitivity.

EDRRM Sensitivity:
High - 60
Medium - 50
Low - 35

The following is my understanding of the EDRRM sensitivity in terms of AQI:
High: 51 - 60
Medium: 36 - 50
Low: 0 - 35

So I would think the answer is 'Medium' as 40 falls in the 36-50 AQI

Andrew (
http://revolutionwifi.blogspot.com.au/2010/10/cisco-cleanair-review.html)
mentions "High Sensitivity requires AQI to fall below 60, Medium Sensitivity 
requires AQI below 50, and Low Sensitivity requires AQI below 35." This from my 
point of view is the following:
High: 50 - 59
Medium: 35 - 49
Low: 0 - 34

>From the WLC 7.0.116 guide under CleanAir EDRRM, "When the interference 
>for
the access point rises above the threshold level, RRM initiates a local dynamic 
channel assignment (DCA) run and changes the channel of the affected access 
point radio if possible to improve network performance."
This is a bit confusing as it mentions "interference" when we are directly 
dealing with "AQI". High interference means low AQI and low interference means 
high AQI.

Usually I will just lab the scenario out to understand it but I think this is a 
bit hard and I don't have right equipment to create wireless interference to 
the precise AQI value.

Is this just a typo in the Solutions Guide? Or my brain is just fried from 
studying too much 2 weeks prior to the lab exam? Taking the lab exam in Sydney 
on the 29th of January.

Thanks.

Regards,
Jeen Sern Chew
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