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RE: QOS order of operation posted 01/01/2006
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I know your frustration.

But, don't despair.  There's a document on the Cisco site that spells on the
order of operations.

You can search for it on the Cisco site or you can search the GS archives.
The link for that document has been posted on GS - I just don't remember

HTH, Tim

-----Original Message-----
From: nobody@xxxxxxxxxxxxxx [mailto:nobody@xxxxxxxxxxxxxx] On Behalf Of Curt
Sent: Sunday, January 01, 2006 3:53 PM
To: ccielab@xxxxxxxxxxxxxx
Subject: QOS order of operation


I'm trying to better understand all the QoS related concepts and tools.  I'm
reading the Wendell Odom Cisco QoS book (second edition) for the 2nd time.
explains in great detail about how each queuing tool works by itself, but
I try to visualize how they all work together, I am constantly confused by
changing diagrams, and the inclusion of subinterfaces.

My biggest point of confusion lies in the placement of the queue, shaper,
scheduler, as well as where an interface software queue lies in relation to
the class-based queue(s).

I'm really going out on a limb here, mostly using "intuitive-leaps"
but this seems to be the order of operation to the best of my knowledge when
configured on a single physical interface:

1.   Fragmentation (if configured)
2.   Classification
3.   Any nested service-policies configured
4.   Compression
5.   Policing
6.   Drop policy (fifo, WRED)
7.   Queuing
8.   Shaping
9.   Sheduler (between different classes?)
10. Tx-ring.

Am I looking at this all wrong?  Is there a different logical way I should
looking at this?  Is there a another resource that explains this better?



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