Internet 101: The Cables Connecting the World

So admittedly I am not the most tech-savvy person. So, if you are, please feel free to fly through my wonderment at how crazy the concept of Internet is and how the actual process goes down. Now, internet and wifi is something that is so widely available and the norm now-a-days, in the majority of the world. For the average user who walks into their home and connects automatically to wifi, it's probably not even something you spare much thought about. For me, I never really thought much into how it actually worked. It was just like having magical internet particles all around you in the air - at home, at uni, on public transport, everywhere basically - that allowed you to watch videos and talk in group chats and read online articles and be connected with the rest of the world at all times. Nothing that impressive.

BUT THEN Mr. Human (who is much more technologically adept than I) explained to me that internet is basically just the connection of computers around the world through cables. To start basic, imagine you connect two of your computers at home to each other, creating a local area network (LAN). They can now talk to each other through the cable, you can send files, etc. Now multiple that by millions and billions. Imagine each computer around the world is actually connected to each other through 'imaginary cables'. Now, I say 'imaginary cables' because with the invention of the router thus enabling wifi, we have been able to forego the actual physical connection. But that router you're using is still connected to cables which is connected to other cables connected to even more cables which eventually link with other cables all around the world.

Now here's the best part. See, I live in Australia - a country that is basically half-way across the majority of the world. Does that mean we have huuUUUUuuUUUuuge internet cable running along the entire ocean connecting us to far continents such as US and Europe? THAT is what's connecting us with the rest of the world?? NOT the magical particles in the air???

The answer, my friends, is yes. I was shocked too, it's okay to be shocked. Let it out.

So let's check this out. I've sourced the below from Submarine Cable Map so you can definitely also check it out there in more detail.

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You can see here a wire making it's lone solo journey from Australia to Africa. You can do it, lil fella, you can do it. And how Australia's connected directly to Asia with just a few cables from Western Australia. And then you'll notice that a bunch of cables seem to link into the middle of nowhere in the Pacific Ocean...

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So, everybody, this is Guam. Guam, everybody. But of course, he probably already knows you. Seeing as this little internet island secretly controls the whole world's internet. I'm kidding haha. Or am I??

But actually Guam is an "organised, unincorporated territory of the United States" which acts as a major hub for submarine cables (the name for these cross-sea internet cables, more on this later). Currently, it is home to 12 submarine cables from around the world, wanting to connect through the Pacific Ocean.

Global Internet Cables III

Here you can have closer looks at the huge amount of cables connecting between the EU and US, as well as South America and Africa. An interesting tidbit, a lot of the market for submarine cables is actually owned by the EU with the US not playing that significant a part. This is actually because the US didn't find a lot of need to connect with other countries, compared to the desire for other countries to connect with the US. Oh US, you superstar.

Global Internet Cables II

Now, I'm just gonna share some stuff I find interesting about how these cables are actually LAID DOWN throughout the oceans. I read the entire process from this Quora answer for "How are major undersea cables laid in the ocean?" But if you don't have time, I've done a summary:

  • Specially-made ships lay out these submarine cables according to specific charts outlined by the cable operator.

Specialised submarine cable ships

  • These ships are capable of carrying up to 2,000km of cable. This might look something like this, and actually takes a few WEEKS to wind it all around.

Coiled submarine cables waiting to be laid

  • The cable is fed out onto the water into a plough that is dragged behind the ship along the ocean bed. This plough does what it does best - ploughs that internet cable into the oceanbed so that people around the world can be given their life sustenance.

  • For a scale of how big these submarine cables are, see below. What even, right?? I imagined they would be huuuuge to carry all that precious data that people are uploading every single second. But no. They the size of yo thigh.

  • And now let's look below at what components actually make up the insides of these submarine cables. Note that the copper/aluminium tube part (6) is NOT where the data is  transmitted, contrary to Australia's pre-NBN love for the copper wire. This part actually just helps to power the optical fibres.

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  • Okay now, hold up. Let's notice that the actual part which is transmitting all the data makes up SUCH a small component of the whole thing. For a real-life look, see below. I think this highlights just how far our technology has come. That the sheer amount of data generated around the world can be transported across the oceans in a few optical fibres, at the speed of light. Science, you crazy thang.


Some additionally info for fun

  • These cables need to be replaced about every 10 years
  • Costs vary for different projects (e.g. different depth of ocean required, length of cable) but are around US $100 - 500 million per project
  • Why aren't satellites used instead? Seems less cumbersome. But actually satellites aren't able to "carry a terrabyte of data for less than a billion dollars per communication line"
  • Submarine cables are privately owned. Telecommunication companies generally chip into projects together and then share the bandwidth rights, selling accessibility and related products onto the final users.

And that kids was all for today's Technology lesson. If there's anything wrong from the above, or if you'd like to provide more details, then feel free to drop a comment below. As I said, tech-savvy I am not. So I am always open to learning about it.

Hope you enjoyed reading about this, I was so excited to share it all after I found out. Hope it might blow someone's mind who hadn't thought about it before, like it did mine haha. :)