During one of my training sessions someone asked me:
Why is it that none of our providers can give us a ping shorter than 150ms to the “internet”?
And the simple answer is: We can’t beat the physics!!
Let me explain:
Actually, before starting, to those in Europe or the Americas who live “inside the internet” and are used to less than 30ms to most services let me show you where I live: Angola!
Now I’ll explain:
As if this was not enough, cables will not go through mountains, buildings and can’t go between countries suspended in posts. As if this wasn’t enough, to run their way through sea, cables have to go away from the coast and go around that big coast line “bump”. Because of this, the actual distance can double or triple.
To run any distance takes time. The time required to travel this distance depends on the speed. In the case of submarine fiber-optic cables, the speed to consider is the speed of light in the optical fiber. This is approximately 200.000 km/s, 2/3 the speed of light in the vacuum (~300,000 km/s).
From the above, we can see that no provider can significantly reduce the average 150ms to the internet unless it can increase the speed of light on the fiber optic or reduce the distance between continents (hahahah).
And if your calculations and guessing show you smaller values, don’t forget that equipment all along the path (repeaters, switches, routers) and the access technology you are currently using (Wi-Fi, WiMAX, LTE…) all add a few milliseconds to the equation.
But, are there alternatives?
Like almost everything, of course there is: bringing the “internet” closer to us. But I won’t go through this here as the topic was already touched on ina previous article about IXPs.
Note 1: I am not a specialist in undersea communications or the physics involved in fibre optics cables. This post was written to be presented in a simple and clear language.
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