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name Punditsdkoslkdosdkoskdo

Is ping faster than light?

I just discovered very strange thing while testing my internet connection. My ping is smaller than it should be. For example ping time to Arizona State University is about 14ms.

[email protected]:~$ ping
PING ( 56(84) bytes of data.
64 bytes from icmp_seq=1 ttl=60 time=13.8 ms

I'm living in Poznań in Poland so my distance to Arizona State University in a straight line (very optimistic assumption) is about 10000 km. Considering the fact that ping time is a time for two directions (to the target and back to home). So my ping packet have to cross 20000 km distance. Speed of light is 300 000 km per second that is 300km per millisecond. So the smallest possible time to ping Arizona State University with my packet travelling at a speed of light is


I have noticed similar results for servers located in Australia and some other States of America. Is my internet connection five times faster than light?

It is mainly because of the fact that the address has been logically setup at many systems or data stations across the world and your ping reaches the nearest host to you. is an Anycast address. This means that there can be hundreds of nodes that have this address scattered all over the Internet, all providing a same function (for eg. here provides DNS lookup). 
Each network that has a Google DNS server injects a route (, to be specific) into the global BGP (Border Gateway Protocol) routing table. A quick BGP lookup at a random Internet router shows 10 different paths to that network. Your ISP will carry your DNS lookups to the server closes to you.

If we’d ignored this setting of the address (i.e. above logical setup was not done), it would take so much more time (slower than speed of light) for that ping request to travel and complete.

So, if we assume that a “ping” travels with the speed of light (~ 2.99792x10^8 m/s), (Practically, in Optical Fibres, light travels about 31% slower) which are the best possible response times we can get?

10 km => 0,067 milliseconds
100 km => 0,67 milliseconds
1,000 km => 6,7 milliseconds
10,000 km => 67 milliseconds

Hence, for your ping request to complete, it would take more than 100 ms.

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As you can see from the output, you aren’t actually pinging some server in Arizona or even the United States. Apparently, they decided to protect their website with Cloudflare, which employs a content distribution network to even the load. A CDN works with many nodes, each servicing a (geographic) region. That means the node you’re pinging is very close to you.

Because Cloudflare uses Anycast (Wikipedia info) with all of their data centers, you’ll connect to the same IP address no matter where you are in the world. Every data center offers all services. Internet routers decide on the best route (to the closest/best reachable data center) and direct your connection that way.

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