It's not been discussed recently (I'm a relatively new lurker) but some
types of burst might be easily classifiable.

In particular, if a video or voice stream requires no less than X KB/S,
has a second's "headroom" in the form of delivered but undisplayed data
and suffers a 1-second outage, then it should be expected to emit a
burst of 2X before settling back down to its previous rate. The AQM
system should permit this, while at the same time defending its stream
of X from bursts from elsewhere that would starve it for a second or more.

In principle, this kind of analysis can be applied to interactive
communications, with latency and user think time taking the place of
throughput and headroom in the logic. For any given stream, a (moving)
average of its needs can be discovered.

Batch transfers are harder to characterize, but at the same time can be
split into "a human is actively waiting for this" and "get it done for
tomorrow" classes (;-))

This kind of "no less than" resource management is something that has
been well-studied, and substantial work (IBM's "goal mode") was done as
long ago as the mainframe era. 

In capacity planning, one often sets guarantees that a database write
process get no less than a certain amount of resources, and then
constructs trend watchers to ensure that the database's own growth in
activity doesn't render the guarantee too small. This is quite ordinary
"state of practice" work for a planner,  and is often applied
holus-bolus to short-run networks like cluster interconnects.

Researchers in queuing-network models will know much more about the
state of the art, and how it can be applied to AQM.

--dave (a capacity planner and user of queuing networks) c-b

On 12/15/2013 12:35 AM, Naeem Khademi wrote:
> Hi all 
>
> I'm not sure if this has already been covered in any of the other
> threads, but looking at
> http://www.ietf.org/proceedings/88/slides/slides-88-aqm-5.pdf
> and draft-ietf-aqm-recommendation-00, the question remains: "what is a
> good burst (size) that AQMs should allow?" and/or "how an AQM can have
> a notion of the right burst size?". 
>
> and how "naturally-occuring bursts" mentioned
> in draft-ietf-aqm-recommendation-00 can be defined? 
>
> Regards,
> Naeem 
>
>
> _______________________________________________
> aqm mailing list
> [email protected]
> https://www.ietf.org/mailman/listinfo/aqm


-- 
David Collier-Brown,         | Always do right. This will gratify
System Programmer and Author | some people and astonish the rest
[email protected]           |                      -- Mark Twain
(416) 223-8968

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