# Ping + measure circumference of earth

#### ranger

Gold Member
I can remember reading somewhere that the ping command can be used to measure the circumference of the earth or something similar. Does anyone know how to do this, or have a link to the article?

--thanks

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#### Anttech

I doubt it...

the "Ping" command is just a ICMP echo request, each device you ask for the echo will respond quicker or slower depending on cetain factors such as:

Router Ques between your device and end device
Router CPU use between your device and end device
End device CPU use

etc etc

So IMO there is no way one could concievably (using the internet) calculate the Cirumference of the earch using ICMP... Too many external factors would corrupt your data

#### ranger

Gold Member
I've googled for it, but nothing. Hey but I did read something (I guess).

#### TenaliRaman

ranger said:
I can remember reading somewhere that the ping command can be used to measure the circumference of the earth or something similar. Does anyone know how to do this, or have a link to the article
--thanks
Methodology,
2. Buy very long lan cables!!
Connect the two PCs on lan with the wire going around the earth. (Make sure there are sufficient repeaters in between). Ping the second PC from the first PC and calculate the delay in response. Given that the speed ofelectrons through a lan cable is normally around (2/3)c. One can easily calculate an approximate figure for the circumference of the earth.

-- AI
P.S-> Note that the above methodology is still under development and my stupid sidekick is constantly suggesting , "why not just measure the length of the cable?". Pfft! who has heard of such a dumb idea of calculating circumference!!

#### ranger

Gold Member
TenaliRaman said:
Methodology,
2. Buy very long lan cables!!
Connect the two PCs on lan with the wire going around the earth. (Make sure there are sufficient repeaters in between). Ping the second PC from the first PC and calculate the delay in response. Given that the speed ofelectrons through a lan cable is normally around (2/3)c. One can easily calculate an approximate figure for the circumference of the earth.
Insead of that, is it possible to bounce the connection around until it eventually reaches around the earth? Or just get the ip address of a comp halfway around the earth and ping that . Then double the delay responce time.

#### ComputerGeek

I could ping the a website which is set up next door to me and it could bounce half way around the world before it got to the website and return a ping response.

#### ranger

Gold Member
ComputerGeek said:
I could ping the a website which is set up next door to me and it could bounce half way around the world before it got to the website and return a ping response.
When you ping computer, should it find the shortest possible route to the target computer?

"Ping + measure circumference of earth"

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