Eduardo Duarte

Gestão e Desenvolvimento de Projetos l Project Development Management

 

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Hi,

On 22-11-17, Eduardo Duarte wrote:

Hi all,

After the recent launch of the Quad9 service I try to discover if it had
a best response time them my actual resolver, that is google public DNS.

To do this I launch a comparing measurement using atlas that would run
during one day to the same address from the probes in my ISP.
The address that I was trying has a very high TTL so I was expecting to
always hit the cache of the servers and them get a good comparison base.
I know that there are other factors involve in server response time but
to my home connection I fill that this where enough.

Instead of asking for a regular name, you can query a special name like
"version.bind" in the CHAOS class.  These queries are always answered
directly, so it simulates a 100% cache hit and allows you to measure the
RTT towards a resolver.

To test with dig:

  $ dig @9.9.9.9 CH version.bind TXT

See https://atlas.ripe.net/measurements/9740262/ for a real measurement
using this technique.

Baptiste

When I got the results from the measurement they were not what I
expected.... The measurements to Quad9 had high value of REFUSAL.

Does any one as a clue why???

The measurement result is available at
https://atlas.ripe.net/measurements/10269508

Best regards,