[RSSAC Caucus] [Ext] [Non-DoD Source] Re: FOR REVIEW: Requirements for Measurements of the Local Perspective on the Root Server System

[Warren Kumari]

On Fri, Aug 27, 2021 at 4:23 AM Ray Bellis <ray at isc.org> wrote:

>
>
> On 27/08/2021 00:07, Wessels, Duane via rssac-caucus wrote:
>
> > I don't agree that additional analysis is needed, nor do I think this
> > document needs to specify rules or formulas for calculating last mile
> > latency, at this time.  While those things might be really nice to
> > have, I don't think we have the collective will to come to agreement
> > on that in any reasonable amount of time.
> >
> > I think it will have to suffice to leave the interpretation of any
> > reference latency measurements to the party performing the data
> > analysis.  Since this is all new we don't have to get it right the
> > first time.  If it turns out to be wrong or useless or
> > under-specified then we can revise the document after acquiring some
> > experience.
>
>
> I agree.  My recollection is that we made a conscious decision not to
> include a methodologuy for extracting a last-mile baseline in this
> initial version.
>

It's also useful as an intuitive / manual check. We can figure out the
exact [median|mean|n-th percentile] later.
If the latency to various root servers is around 300ms, and the latency
from that same network is 250 ms to Cloudflare, 350 ms to GPDNS, 800 ms to
OpenDNS, and 500 ms to Quad9, then it suggests that that network has other
issues, and those should be investigated before assuming that a closer root
server instance would help.
If the latency to various root servers is around 300ms, and the latency
from that same network is 2.5 ms to Cloudflare, 3.5 ms to GPDNS, 8.0 ms to
OpenDNS, and 5.0 ms to Quad9, then it suggests that that network could
benefit from closer root-server instances, and also that it is likely that
they can be deployed[0].

I cannot easily provide a proof of the above[1], but intuitively it seems
correct,
W
[0]: Actually, I suspect that in that case, there are other issues that
need to be investigated - I find it unlikely that there would be that wide
a latency spread without some other confounding factors, but I wanted to be
able to reuse the numbers from above :-)
[1]: Although I'm sure I could handwave some sort of plausible sounding
statement about X standard deviations away from the mean of Y measurements
(after discarding Q outliers) against Z well connected public servers.



>
> Ray
> _______________________________________________
> rssac-caucus mailing list
> rssac-caucus at icann.org
> https://mm.icann.org/mailman/listinfo/rssac-caucus
>
> _______________________________________________
> By submitting your personal data, you consent to the processing of your
> personal data for purposes of subscribing to this mailing list accordance
> with the ICANN Privacy Policy (https://www.icann.org/privacy/policy) and
> the website Terms of Service (https://www.icann.org/privacy/tos). You can
> visit the Mailman link above to change your membership status or
> configuration, including unsubscribing, setting digest-style delivery or
> disabling delivery altogether (e.g., for a vacation), and so on.
>


-- 
The computing scientist’s main challenge is not to get confused by the
complexities of his own making.
  -- E. W. Dijkstra
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mm.icann.org/pipermail/rssac-caucus/attachments/20210827/8bc18d8d/attachment.html>