The Dunant subsea cable

Old timer story - years ago, Demon Internet (my old employer) was beginning to enter super-growth and wanted to really set itself up for trans-atlantic connections. So they decided to buy a T1 - 45Mbps link across the atlantic. Now it turns out that BT had only ever resold fractions of T1s - they had never actually had anyone want a whole one. And as such their sales commissions did not cap out.<p>So, we rang up, a sales guy picked up the phone and got a million pound pay day, and resigned that evening.<p>But our customers were happy so thats what counts :-)

I know a lot is focusing on the Bandwidth. But are we making any progress on Long Distance Subsea Cable using Hollow Core Cable, achieving close to maximum speed of light for theoretical lowest latency possible? Imagine cutting latency from West Coast US to Hong Kong by 50ms!<p>Light is only traveling at around 2&#x2F;3 of speed within Fibre.<p>The previous decades have been around Bandwidth. Is time we shift out focus to latency. 5G is already part of that , and 6G is further pushing it as standard feature. I wish other part of network start thinking about Latency too.<p>May be not network, but everything. From out input devices to Display. We need to enter the new age of Minimal Latency Computing.

You could load a modern Javascript-powered website in less than a minute with that.

I know there are many of these cables that have been around for years, but I am curious how are they physically secured? Especially where they transit from ocean to land? Is there some long underground&#x2F;sea tunnel of conduit that the cable is routed through to the basement of some building? Or if you are walking along the beach somewhere is there just some cable running out of the ocean along the beach to some building near the shore?<p>I also wonder what kind of permissions and licenses you need to seek to run a cable across the ocean floor?

Wow, talk about a barrier to entry. Google already has Curie from North America to South America and Equiano from Portugal to South Africa. They&#x27;re also working on Hopper from North America to UK and Spain:<p><a href="https:&#x2F;&#x2F;cloud.google.com&#x2F;blog&#x2F;products&#x2F;infrastructure&#x2F;announcing-googles-grace-hopper-subsea-cable-system" rel="nofollow">https:&#x2F;&#x2F;cloud.google.com&#x2F;blog&#x2F;products&#x2F;infrastructure&#x2F;announ...</a><p>I presume that the other trillion-dollar companies are getting in on the action too.

This is super-cool! I found &quot;enough to transmit the entire digitized Library of Congress three times every second&quot; to be a really weird comparison though - I&#x27;m used to text being really small and compressible, and I doubt many people have an intuitive grasp of how much One Scanned Library of Congress is. How many hour-long Netflix&#x2F;YouTube episodes per second, on the other hand...

The article mentions the number of fibres in this cable is 12, and that new technology was used to increase that number.<p>What is the limit on how many fibres can go in a cable? Should we expect future cables to have 50 fibres, or 100, or 1000, or more?

I know nothing of this type of engineering. How do you even start a project like this? Map the bottom of the ocean, figure out all the danger zones? What is the cost of doing something like this?

The article says this cable uses SDM (space division multiplexing). Which, for fiberoptics, means that you have multiple fibers. Of course they HAVE TO put many wavelengths on each fiber, each wavelength carrying a signal.<p>The &quot;state-of-the-art&quot; AFAIK is to use many wavelengths per fiber, each one carrying ~192 wavelengths each wavelength transporting at up to 100Gbps (this is known as DWDM).<p>So so with SDM, you just have more fibers? So what? It seems like I am missing something here? Why is &quot;SDM&quot; the key concept rather than &quot;DWDM&quot;? Why not just say DWDM with 12 fiber pairs?

Do those come with pre attached NSA listening devices [1] ?<p>[1] <a href="https:&#x2F;&#x2F;siliconangle.com&#x2F;2013&#x2F;07&#x2F;19&#x2F;how-the-nsa-taps-undersea-fiber-optic-cables&#x2F;" rel="nofollow">https:&#x2F;&#x2F;siliconangle.com&#x2F;2013&#x2F;07&#x2F;19&#x2F;how-the-nsa-taps-underse...</a>

Excellent related Ars Technica article related to deep-sea cables if you want to learn more: <a href="https:&#x2F;&#x2F;arstechnica.com&#x2F;information-technology&#x2F;2016&#x2F;05&#x2F;how-the-internet-works-submarine-cables-data-centres-last-mile&#x2F;" rel="nofollow">https:&#x2F;&#x2F;arstechnica.com&#x2F;information-technology&#x2F;2016&#x2F;05&#x2F;how-t...</a>

Ah the old &quot;entire digitized Library of Congress&quot; per second metric

If anyone enjoys this topic, I would recommend reading &quot;A Thread Across the Ocean: The Heroic Story of the Transatlantic Cable&quot; by John Steele Gordon.

“ enough to transmit the entire digitized Library of Congress three times every second” the engineer in me: compressed? With images? Or just raw texts?

This is a video from google about how laying undersea cables works: <a href="https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=H9R4tznCNB0" rel="nofollow">https:&#x2F;&#x2F;www.youtube.com&#x2F;watch?v=H9R4tznCNB0</a> I&#x27;ve always wanted to know! Super cool!

No mention of latency improvements?<p>Seems crazy since oversea transit (tcp &amp; single-channel) is usually latency (or loss) bound.<p>I would expect it&#x27;s better than going over public transit and legacy subsea fiber, but it would have been useful to see some comparison tests between POPs.

Is Google using this for consumer services (Gmail&#x2F;Search&#x2F;YouTube&#x2F;Stadia) that don&#x27;t run on GCP or is this only for GCP? If it&#x27;s only for GCP, they are betting big, which is good.

I see a lot of these fiber lines pop up on tiny islands throughout the pacific. What’s happening at these places? Are there people who work there and if so what are they doing?

For those of you who haven’t read Neal Stephenson’s Wired article on submarine cables from 25 years ago.<p><a href="https:&#x2F;&#x2F;www.wired.com&#x2F;1996&#x2F;12&#x2F;ffglass&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.wired.com&#x2F;1996&#x2F;12&#x2F;ffglass&#x2F;</a>

&gt; will deliver record-breaking capacity of 250 terabits per second (Tbps) across the ocean—enough to transmit the entire digitized Library of Congress three times every second.<p>Damn. Anyone else just agog at this figure?

TechCrunch story about this posted yesterday:<p><a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=26017592" rel="nofollow">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=26017592</a>

My Firefox Developer Edition (86) doesn&#x27;t load the page completely, one of the resources (<a href="https:&#x2F;&#x2F;gweb-cloudblog-publish.appspot.com&#x2F;api&#x2F;w_v2&#x2F;pagesByUrl&#x2F;home&#x2F;?b=1612399295404" rel="nofollow">https:&#x2F;&#x2F;gweb-cloudblog-publish.appspot.com&#x2F;api&#x2F;w_v2&#x2F;pagesByU...</a>) has an untrusted certificate (SEC_ERROR_UNKNOWN_ISSUER). It is issued by &quot;Cisco Umbrella Secondary SubCA&quot;.

Oh dear! how is NSA going wiretap that ?

Is this only for Google traffic?

Is this a private cable that only connects Google datacenters? If so, too bad for open, neutral Internet.

Anyone who has some clue wants to take a shot at what could be investment cost for such a cable?

This cable is not just to be used by Google right? Or am I misunderstanding something? Fundamentally, infrastructure should be publicly owned and then rented by companies to use it, in this case it seems like Google physically owns the cables and infrastructure which would be a massive waste.

I&#x27;m delighted by all the speculation in this thread about whether the cable laid by the global surveillance company is somehow being spied on.

Sigh... Removed because people don&#x27;t seem to want to see it.<p>Not a big deal, but...<i>sheesh</i>. It&#x27;s not like it was a troll comment; just a relatively lighthearted poke.

Is this why they&#x27;re losing billions?