Re: comments on draft-dcbench-def-00 (part 1)

On 7/31/13 11:07 AM, MORTON JR., ALFRED C (AL) wrote:

> I assumed we have benchmarked a single device, and wanted to
> estimate how some number of these devices would affect delay 
> variation when deployed on the path. Clearly, if we can benchmark
> a particular black-box SUT with a specific combination of these devices,
> there's no need to do the estimation for that case.
> But having the ability to estimate e2e variation for an unknown number on the path
> seems valuable to me, and I wonder if Data Center Engineers agree.
> 
> it's been a long day here, hope this makes sense,

Mostly. Agreed 100 percent on the requirement for e2e estimation.

Unclear how that estimate would differ from a single-box estimate times
some number of identical boxes, modulo cable lengths.

And regardless of box count, there's still the question of which  method
of jitter measurement to use.

That was my original point: Given so many definitions to choose from,
it'd be nice to spell out one definition in this document, either
referencing something else, or defining something new (as in the use of
FILO for latency measurement).

dn