Thursday, 22 November 2012

Is Google DNS a Myth?

Google public DNS resolving services on IP addresses 8.8.8.8 and 8.8.4.4 was sold as being a faster solution for users, since caching could occur on a massive scale, but is it just a statistics gathering exercise for Google?

Using NameBench (http://code.google.com/p/namebench/), and running the test, it looks as if Google DNS is actually slower than local services, and popular global ones:


Mean Response Duration

Mean Duration Graph

Fastest Individual Response Duration

Fastest Response Graph

Response Distribution Chart (First 200ms)

Response Distribution Graph (first 200ms)

Response Distribution Chart (Full)

Response Distribution Graph (full)

DNS Speed testing.

DNS Speed testing.

I've often used ZoneCheck to test if DNS is set up correctly, but it doesn't give an indication of performance,
for that, I'd recommend https://www.ultratools.com/tools/dnsHostingSpeedResult - Check for "A" record response, where you should aim to get a response time of 50ms or less.

Here is a speed check of this blog, which is hosted by Google.


freenameservers.blogspot.co.uk

Name ServerAAAACNAMEMXSOAASPFSRVTXT
ns3.google.com.3830383131313139
ns4.google.com.32333233
ns2.google.com.1313131314121313
ns1.google.com.1615171616161716
Min. Time(ms)32333233
Max. Time(ms)3830383131313139
Avg. Time(ms)1715171516151617

co.uk.

ns5.nic.uk.85 ms
nsa.nic.uk.10 ms
ns4.nic.uk.87 ms
ns2.nic.uk.88 ms
ns1.nic.uk.101 ms
ns7.nic.uk.82 ms
ns6.nic.uk.88 ms
nsb.nic.uk.2 ms
nsd.nic.uk.10 ms
nsc.nic.uk.2 ms
ns3.nic.uk.80 ms
Min. Time: 2 ms  Max. Time: 101 ms  Avg. Time: 57 ms

TLD Servers

ns4.nic.uk.79 ms
ns1.nic.uk.101 ms
ns3.nic.uk.91 ms
ns2.nic.uk.86 ms
ns6.nic.uk.90 ms
nsc.nic.uk.2 ms
ns5.nic.uk.86 ms
nsa.nic.uk.10 ms
nsd.nic.uk.10 ms
nsb.nic.uk.2 ms
ns7.nic.uk.82 ms
Min. Time: 2 ms  Max. Time: 101 ms  Avg. Time: 58 ms

Root Servers

h.root-servers.net. (H3)5 ms
k.root-servers.net. (k3.linx.k.ripe.net)97 ms
a.root-servers.net. ()231 ms
c.root-servers.net. (iad1a.c.root-servers.org)2 ms
l.root-servers.net. (dnd01.l.root-servers.org)92 ms
e.root-servers.net. (e5.arc.nasa.gov)80 ms
m.root-servers.net. (M-CDG-1)85 ms
i.root-servers.net. (s1.bnx)92 ms
f.root-servers.net. (scl1a.f.root-servers.org)166 ms
d.root-servers.net. (css-d.net.umd.edu)3 ms
b.root-servers.net. (b8)65 ms
j.root-servers.net. (jluepe1-elstk2)139 ms
g.root-servers.net. (g.root-servers2.net)35 ms
Min. Time: 2 ms  Max. Time: 231 ms  Avg. Time: 84 ms