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1895 points _l4jh | 1 comments | | HN request time: 0s | source
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cleanbrowsing ◴[] No.16729310[source]
And look at these ping times:

                                   CloudFlare       Google DNS       Quad9            OpenDNS          
  NewYork                            2 msec           1 msec           2 msec           19 msec          
  Toronto                            2 msec           28 msec          17 msec          27 msec          
  Atlanta                            1 msec           2 msec           1 msec           19 msec          
  Dallas                             1 msec           9 msec           1 msec           7 msec           
  San Francisco                      3 msec           21 msec          15 msec          20 msec          
  London                             1 msec           12 msec          1 msec           14 msec          
  Amsterdam                          2 msec           6 msec           1 msec           6 msec           
  Frankfurt                          1 msec           9 msec           2 msec           9 msec           
  Tokyo                              2 msec           2 msec           81 msec          77 msec          
  Singapore                          2 msec           2 msec           1 msec           189 msec         
  Sydney                             1 msec           130 msec         1 msec           165 msec

Very impressive CloudFlare.
replies(20): >>16729423 #>>16729467 #>>16729545 #>>16729560 #>>16729939 #>>16729952 #>>16730034 #>>16730110 #>>16730198 #>>16730229 #>>16730567 #>>16730893 #>>16731389 #>>16732068 #>>16732273 #>>16732936 #>>16733149 #>>16733462 #>>16733833 #>>16761330 #
fipple ◴[] No.16729423[source]
How is this possible from a single location? The speed of light in a vacuum is ~200 miles per millisecond.
replies(1): >>16729433 #
aftbit ◴[] No.16729433[source]
Despite using a single IP, this is not served from a single location. Check out Anycast, wikipedia: https://en.wikipedia.org/wiki/Anycast
replies(1): >>16730497 #
1. tialaramex ◴[] No.16730497[source]
Yup, anycast, this is also why:

The "backup" IPv4 address is 1.0.0.1 rather than, say, 1.1.1.2, and why they needed APNIC's help to make this work

In theory you can tell other network providers "Hi, we want you to route this single special address 1.1.1.1 to us" and that would work. But in practice most of them have a rule which says "The smallest routes we care about are a /24" and 1.1.1.1 on its own is a /32. So what gets done about that is you need to route the entire /24 to make this work, and although you can put other services in that /24 if you _really_ want, they will all get routed together, including failover routing and other practices. So, it's usually best to "waste" an entire /24 on a single anycast service. Anycast is not exactly a cheap homebrew thing, so a /24 isn't _that_ much to use up.