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All major data carriers these days use fiber optic links these days. And data transmission occurs at the speed of light, is that correct?

If data transmission does indeed occur at the speed of light, is it also correct to assume that data transmission will never ever be faster?

Update: I have posted another question. I have realized due to my lack of knowledge regarding these concepts, I have posted the wrong question. Thank you for your responses. They've been really intriguing.

Other question:

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The individual states of the light (on/off) are at the speed of light to the other end the line, however data transmission is far far slower.

You have the switching times on the components turning on and off the light, speed of connectivity between the computer and these components which is think is the main thing that determines achievable speeds on fiber. Also the overhead of the protocol

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Fiber-optic signal does go down fiber-optic cable (or radio waves on satellite links) at the speed of light, so obviously that can never go faster, baring weird quantum things. It's the slower parts that can be sped up - transmission on other media, switching, routing, effects due to congestion.

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Not even weird quantum things can get data to go faster than the speed of light (in a vacuum). – David Z Apr 23 '10 at 3:41
Quantum entanglement. – mfinni Apr 23 '10 at 3:45

No, it is not safe to assume this. It is obvious that it will be exceeded to anyone who watches:

  • Dr. Who
  • Star Trek
  • Batllestar Gallatecia
  • etc

Just a matter of time ... or space .. depending on how you want to look at it.

In all seriousness, for the most part this doesn't really matter that much. With the current protocols, as long as you set a significantly large buffer you are going to get good transfer rates. Even around the world in a sense isn't that much latency.

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The speed of light in fibre is about 2/3 the speed of light in a vacuum, or 200,000 km per second. Additional latency is incurred by the routers and switches on the path.

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If you can get it to go faster than light, congratulations on the Nobel Prize.

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The speed is near C (speed of light). C = C in a vacuum, and glass/air/etc. is not a vacuum. Materials have different refractive indexes, so the actual speed varies. Also, once you leave the long-haul network, which is mostly (all?) fiber and touch copper, you are even slower. So transmission speeds can still increase.

And the other factors affecting transmission speed, hops e.g., can be made faster.

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Using good compression you can move data much faster.

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