From: George Roman (georgeroman@gmail.com)
Date: Tue Mar 31 2009 - 19:19:24 ART
Hi Ruhann,
Here is how this works:
-when you reach the lower limit (50 packets in your case) in the Q you start
dropping packets than as bigger your queue gets you will be more aggressive
on your drop (this drop is proportional to the value you set for the MPD).
-When you reach higher limit (70 packets in your case) you will drop with
the value you are set for the MPD. In your case if the value is 4 (this is
the denominator) you will drop 1 out of 4 packets from the queue.
After you exceed 70 packets you have taildrop.
Best regards,
George
On Tue, Mar 31, 2009 at 10:42 PM, Ruhann <groupstudy@ru.co.za> wrote:
> Hi peoples
>
> I would like to double check something I dont agree with.
>
> The question states as follow:
> Congestion Avoidance:
>
> - Configure R6 to randomly drop packets before congestion occurs on the
> Serial interface output queue.
> - Ensure that traffic marked with critical precedence will not be dropped
> unless there are 50 packets in the output queue.
> - If there are 70 critical packets in the output queue, R6 should
> randomly drop 4 out of every 16 of these packets.
> - In the case that there are more than 70 critical packets in the output
> queue, they should all be dropped.
> - Do not use any MQC commands to accomplish this task.
>
>
> My solution to this was as follow:
> interface Serial0/0
> random-detect
> random-detect precedence 5 50 70 4
>
> My question is about the MPD value to be worked out here.
> How I understand this, to work out your MPD value you take 1/MPD to see the
> initial stage of RED,
> in this example 4/16 = 1/4 , so the MPD=4
> thus 1 in every 4 packets will be randomly dropped when RED kick in
> (Q=51).
>
> As the Q depth increases so will the random drops, up until Q=70 where 4/4
> will be dropped?
>
> Am I understanding this right, Cause the answer to this question was the
> MPD
> =8
> ie : random-detect precedence 5 50 70 8
>
> Please share you though and point me right if im wrong. :)
> --
> <ruhann>
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
Blogs and organic groups at http://www.ccie.net
This archive was generated by hypermail 2.1.4 : Mon Apr 06 2009 - 06:44:08 ART